Roof components. The main elements of the roof, features of their installation and maintenance
At the heart of each roof is a large number of beams, rafters, racks and girders, which are collectively called the truss system. Over the centuries-old history of types and methods of its organization, a lot has accumulated, and each has its own characteristics in the construction of knots and cuts. We will talk in more detail about what the gable roof truss system can be and how the rafters and other elements of the system should be attached in more detail.
The design of the gable roof truss system
In the context of a gable roof is a triangle. It consists of two rectangular inclined planes. These two planes are connected at the highest point into a single system with a ridge beam (run).
Now about the components of the system and their purpose:
- Mauerlat - a beam that connects the roof and walls of the building, serves as a support for the rafter legs and other elements of the system.
- Rafter legs - they form the inclined planes of the roof and are the support for the crate under the roofing material.
- Ridge run (bead or ridge) - combines two roof planes.
- A puff is a transverse part that connects opposite rafter legs. Serves to increase the rigidity of the structure and compensate for bursting loads.
- Beds - bars located along the Mauerlat. Redistribute the load from the roof.
- Side runs - support the rafter legs.
- Racks - transfer the load from the runs to the beds.
Filly may still be present in the system. These are boards that extend the rafter legs to form an overhang. The fact is that in order to protect the walls and foundation of the house from precipitation, it is desirable that the roof ends as far as possible from the walls. To do this, you can take long rafter legs. But the standard lumber length of 6 meters is often not enough for this. Ordering non-standard is very expensive. Therefore, the rafters are simply grown, and the boards with which this is done are called “fillies”.
There are quite a few designs of truss systems. First of all, they are divided into two groups - with layered and hanging rafters.
With hanging rafters
These are systems in which the rafter legs rest only on the outer walls without intermediate supports (bearing walls). For gable roofs, the maximum span is 9 meters. When installing a vertical support and a strut system, it can be increased up to 14 meters.
The hanging type of gable roof rafter system is good because in most cases there is no need to install a Mauerlat, and this makes the installation of rafter legs easier: no need to make cuts, just mow the boards. To connect the walls and rafters, a lining is used - a wide board, which is attached to studs, nails, bolts, crossbars. With such a structure, most of the bursting loads are compensated, the impact on the walls is directed vertically downwards.
Types of truss systems with hanging rafters for different spans between load-bearing walls
Gable roof truss system for small houses
There is a cheap version of the truss system when it is a triangle (photo below). Such a structure is possible if the distance between the outer walls is not more than 6 meters. For such a rafter system, it is possible not to calculate the angle of inclination: the ridge must be raised above the puff to a height of at least 1/6 of the span length.
But with this construction, the rafters experience significant bending loads. To compensate for them, they either take rafters of a larger section or cut the ridge part in such a way as to partially neutralize them. To give greater rigidity in the upper part, wooden or metal plates are nailed on both sides, which securely fasten the top of the triangle (also see not the picture).
The photo also shows how to grow rafter legs to create a roof overhang. A notch is made, which should go beyond the line drawn from the inner wall upwards. This is necessary to move the incision site and reduce the likelihood of a rafter breaking.
Ridge knot and fastening of rafter legs to the backing board with a simple version of the system
For mansard roofs
Option with the installation of a crossbar - used when. In this case, it is the basis for filing the ceiling of the room below. For reliable operation of this type of system, the crossbar notch must be hingeless (rigid). The best option is semi-pan (see the picture below). Otherwise, the roof will become unstable to loads.
Please note that in this scheme there is a Mauerlat, and the rafter legs should extend beyond the walls to increase the stability of the structure. To secure them and dock with the Mauerlat, a cut is made in the form of a triangle. In this case, with an uneven load on the slopes, the roof will be more stable.
With such a scheme, almost the entire load falls on the rafters, therefore they must be taken with a larger section. Sometimes the raised puff is reinforced with a suspension. This is necessary to prevent it from sagging if it serves as a support for ceiling sheathing materials. If the puff is short, it can be secured in the center on both sides with boards nailed to the nails. With a significant load and length, there may be several such insurances. In this case, boards and nails are also enough.
For big houses
With a significant distance between the two outer walls, a headstock and struts are installed. This design has high rigidity, since the loads are compensated.
With such a long span (up to 14 meters), it is difficult and expensive to make a one-piece puff, because it is made from two beams. It is connected by a straight or oblique cut (picture below).
For reliable docking, the junction is reinforced with a steel plate mounted on bolts. Its dimensions should be larger than the dimensions of the cut - the extreme bolts are screwed into solid wood at a distance of at least 5 cm from the edge of the cut.
In order for the circuit to work properly, it is necessary to correctly make the struts. They transmit and distribute part of the load from the rafter legs to the puff and provide structural rigidity. Metal strips are used to reinforce the connections.
When assembling a gable roof with hanging rafters, the cross-section of lumber is always larger than in systems with layered rafters: there are fewer load transfer points, therefore, each element has a greater load.
With rafters
In gable roofs with layered rafters, their ends rest on the walls, and the middle part rests on load-bearing walls or columns. Some schemes burst walls, some do not. In any case, the presence of a Mauerlat is mandatory.
Bezporny schemes and knots of cuts
Houses made of logs or timber do not respond well to spacer loads. For them, they are critical: the wall can fall apart. For wooden houses, the gable roof truss system must be non-expansion. Let's talk about the types of such systems in more detail.
The simplest non-spacer scheme of the truss system is shown in the photo below. In it, the rafter leg rests on the Mauerlat. In this embodiment, it works on a bend, without bursting the wall.
Pay attention to the options for attaching the rafter legs to the Mauerlat. In the first, the support platform is usually beveled, while its length is no more than the cross section of the beam. The depth of the cut is no more than 0.25 of its height.
The top of the rafter legs is laid on the ridge beam without fastening it to the opposite rafter. Two shed roofs are obtained according to the structure, which adjoin (but do not connect) one with the other in the upper part.
It is much easier to assemble the option with rafter legs fastened in the ridge part. They almost never give a thrust on the walls.
For this scheme to work, the rafter legs below are attached using a movable joint. To fix the rafter leg to the Mauerlat, one nail is hammered from above or a flexible steel plate is placed from below. See the photo for options for attaching rafter legs to a ridge run.
If the roofing material is planned to be heavy, it is necessary to increase the bearing capacity. This is achieved by increasing the cross section of the elements of the truss system and strengthening the ridge assembly. It is shown in the photo below.
Strengthening the ridge assembly for heavy roofing material or with significant snow loads
All of the above gable roof schemes are stable in the presence of uniform loads. But in practice, this almost never happens. There are two ways to prevent the roof from sliding in the direction of greater load: by installing a brace at a height of about 2 meters or by struts.
Options for truss systems with contractions
The installation of contractions increases the reliability of the structure. In order for it to work normally, at the places where it intersects with drains, you need to attach nails to them. The cross section of the beam for the scrum is used the same as for the rafters.
They are attached to the rafter legs with bots or nails. Can be installed on one or both sides. The knot for attaching the bout to the rafters and the ridge run, see the figure below.
In order for the system to be rigid and not “crawl” even under emergency loads, it is enough in this embodiment to provide a rigid fastening of the ridge beam. In the absence of the possibility of its displacement in the horizontal, the roof will withstand even significant loads.
Rafter systems with braces
In these options, rafter legs, which are also called struts, are added for greater rigidity. They are installed at an angle of 45° with respect to the horizon. Their installation allows you to increase the span length (up to 14 meters) or reduce the cross section of beams (rafters).
The strut is simply substituted at the required angle to the beams and nailed from the sides and bottom. An important requirement: the brace must be cut accurately and fit snugly against the uprights and the rafter leg, excluding the possibility of its deflection.
Systems with rafter legs. Above is a spacer system, below is a non-spacer system. The nodes of the correct felling for each are located nearby. Below - possible schemes for attaching the strut
But not in all houses, the average load-bearing wall is located in the middle. In this case, it is possible to install struts with an angle of inclination relative to the horizon of 45-53 °.
Bracing systems are necessary if significant uneven shrinkage of the foundation or walls is possible. Walls can sit differently on wooden houses, and foundations on layered or heaving soils. In all these cases, consider the installation of truss systems of this type.
System for houses with two internal load-bearing walls
If the house has two load-bearing walls, two rafters are installed, which are located above each of the walls. Beds are laid on the intermediate load-bearing walls, the load from the rafter beams is transferred to the beds through the racks.
In these systems, a ridge run is not installed: it gives expansion forces. The rafters in the upper part are connected to one another (cut and joined without gaps), the joints are reinforced with steel or wooden plates, which are nailed.
In the upper non-expansion system, the expanding force is neutralized by tightening. Please note that the puff is placed under the run. Then it works efficiently (the top diagram in the figure). Stability can be provided by racks, or jointing - beams installed obliquely. In the spacer system (in the picture it is below), the cross member is a crossbar. It is installed above the run.
There is a variant of the system with racks, but without rafters. Then a rack is nailed to each rafter leg, which rests on the intermediate load-bearing wall with the second end.
Fastening the rack and tightening in the rafter system without a rafter run
To fasten the racks, nails for 150 mm and bolts 12 mm are used. Dimensions and distances in the figure are in millimeters.
To learn how to make a roof with your own hands correctly, you need to study a few instructions for doing this rather complicated job. It should be noted right away that there are several types of roofs, each of which has its own device scheme and requires a special approach. In addition, the choice of the type of roof will depend on the purpose of the building that will be covered by it.
Properly erected roof elements will be able to protect the house not only from precipitation, but also keep precious heat inside the building in winter. Therefore, a well-built and insulated roof is no less important than reliable warm walls.
Roof types
As mentioned above, there are several types of roofs. When choosing an option suitable for a particular building, it is worth considering some of them in order to know what they are.
Different types of roofs... To date, the following main types of roofs are satisfied in construction practice: single-pitched, gable with a slope, tent, mansard, hip four-slope, half-hip, multi-slope.
… from the simplest to the most complex shed roof
This option is usually used to cover garages or outbuildings, but sometimes such a roof is also suitable for residential private houses.
Such a design can be called one of the simplest of all existing ones, especially in cases where the slope of the slope is very small. If there are plans to equip another room under the roof, then the design becomes somewhat more complicated. Nevertheless, this type of roof is the most economical in terms of roofing and lumber consumption.
Gable roof
The gable version of the roof is considered traditional for residential buildings, country houses and is installed more often than all other types. Apparently, this is due to the fact that such a roof can be arranged for any structure of the building. The slope of the slopes will depend on the distance between the outer walls and the location of the load-bearing walls inside the house.
hipped roof
This is a fairly complex design, which is almost never used in recent years. However, if it is decided to choose it, then it is better to use a beam-tightening system with struts and racks for the device.
The roof consists of four isosceles triangles - their vertices converge at one point. The hipped roof resembles a tetrahedral pyramid or tent, hence its name.
Double pitched roof
Such a roof is arranged according to the scheme of a gable roof, but it has bevels of different slopes in the front part.
Hip or pitched roof
This design is somewhat reminiscent of a hip roof version, but, unlike it, it has a ridge. The roof is quite complex in design, and most often a scheme with double puffs and beams is used to build it.
Half hip roof
This design has hardly been used in recent years, since it is rather complicated in the device. If it is chosen, then it is mainly arranged according to the truss scheme with puffs.
pitched roof
Such a roof is arranged in houses with complex layouts, or if an extension is made to the main building. The design of a multi-pitched roof is quite complex, and it is used only in extreme cases.
mansard roof
You can’t call a mansard roof simple in execution ... Due to the fact that this design allows you to solve two problems at once - to get an additional room at the same time as a reliable roof, the attic version can be called one of the most popular after the gable type.
... but under certain conditions, a residential attic can also be located under a conventional gable roof Roof slope
It is very important to make the correct slope of the roof - the durability of not only the structure covering the house, but the entire building will depend on this. In regions with cold winters and a lot of snow, the slope plays a particularly important role, since if it is insufficient, then snowdrifts will collect on the surface, which, when melted, can simply fail the roof. That is why it is recommended to make the slope at least 40 ÷ 45 degrees.
In addition to the location of the building, the roofing material also affects the choice of roof slope. So, if it is planned to use tiles or slate for coating, then the slope should not be less than 25 degrees, otherwise water may seep into the attic at the joints, as there will be a small intensity of water runoff.
When constructing a gable structure, the slope is usually made from 30 to 45, and for a single slope 25 ÷ 30 degrees.
Components of the roof structure
In different roof systems, the elements vary, but the main ones still remain the same. These include the following:
- Skate - the upper part of the roof, the place where its slopes are connected. This element is absent in the tent and single-sided version.
- Slopes are the main planes of the roof covered with roofing material.
- Endova - the inner corner of the roof, formed at the junction of two slopes. This element is present only in complex structures. When arranging the roof, valleys should be given special attention during waterproofing work, since such a site is one of the most vulnerable places in the structure, it is in them that the largest accumulation of snow occurs.
- The eaves overhang is the overhang of the roof on the sides of the house. They are installing drainage systems.
- Gable overhang - the protruding part of the slopes above the front side of the roof.
- The rafter system is a structure that is the basis for the installation of slopes. There are several varieties of these systems, but the most reliable of them is the triangle, since it is this figure that gives the structure rigidity.
Rafter systems
Before installing any structure made of wood, the material must first be coated with antiseptics and flame retardants, which can protect it from fungal formations, insect colonies and increase the fire safety of the entire system.
The main element in the rafter system is the rafters, laid on the Mauerlat, supported by racks, fastened with beds and puffs.
In the upper part, the rafters are overlapped and fastened, while the lower ones are fixed to the Mauerlat or to the bars laid between the rafters.
The rafter system has different shapes and can be layered or hanging.
You can make a simplified version when a crate is stuffed on the rafters, and roofing material is immediately laid on top of it. But the very first winter will show that the roof requires insulation. Therefore, it is best to immediately do everything right and not return to this issue again.
Approximate structure of the "sandwich" of the insulated roof - The first thing that is recommended to be done is to sheathe the truss system from the inside with a vapor barrier film. It is stretched and attached to the rafters with a stapler and staples.
- Further, on top of the vapor barrier film, the roof from the attic side is sheathed with drywall plates - it is screwed with self-tapping screws. Drywall will not only give the attic space neatness, but also serve as the basis for insulation boards.
- At the next stage, you will have to climb the roof so that between the rafters, on the vapor barrier film, lay a heater, which is most often mineral wool in mats or rolls.
- A boardwalk is laid on top of the insulation. The boards for it should not be too thick so as not to make the structure heavier. Instead of boards, plywood sheets (or OSB) 4-5 mm thick can also be used.
- The next layer is sheets of waterproofing material - it can be a dense polyethylene film or roofing material. The waterproofing sheets are overlapped by 20 ÷ 25 cm on top of each other.
- On top of the waterproofing, a counter-lattice is arranged, which consists of slats 10–20 mm thick and is stuffed directly onto the rafters.
- By counter-lattice roofing is fixed, with the distance between adjacent guides, which should be less than the tiles, by about 5 mm.
- A frontal board is nailed along the eaves, to which a drain system will later be arranged.
- Before laying the roofing material, hooks are fixed to the rafters, on which drainpipes will be mounted. gutters. After their installation, a cornice strip is installed, which is fixed to the frontal board
- Having arranged the crate and drainage system, you can proceed with the installation of tiles. It starts from the right or left side of the roof, from the bottom row, the tiles are aligned along the edge of the cornice and overlapped, in accordance with the locking system available on it.
- The second row of tiles begins to be laid on the same side as the first - it covers the first row by 50 ÷ 70 mm. Installation is carried out in the same order, up to the roof ridge.
- Having completed laying on the roof slopes, it is necessary to install a ridge at their junction.
- An end bar is fixed to the side rafter, having a size of 25 × 50 mm, and is installed on the corner of the roof corner - stub.
- A self-adhesive sealant is placed between the end bar and the tile.
- The entire side of the roof is closed with an end plate, which is designed to protect the roofing material from wind, which can tear off the coating with strong gusts.
Above, the process of arranging the under-roofing system and roofing with tiles was outlined briefly, with a simple enumeration of the main steps. It probably makes sense to consider it in more detail, literally step by step.
Prices for different types of tiles
Roof tiles
Step-by-step instructions for covering the roof with a tiled roof
Installation of the base under the roofing material
Nowadays, a very wide variety of different roofing materials is presented on the construction market. Nevertheless, tile against this “background” does not lose its popularity, although it is one of the most complex and time-consuming roofing installations.
Ceramic tiles are represented by several European and domestic companies, and it may differ in some design nuances. But the principle of mounting the crate and the coating itself is the same.
For the installation and fixing of the tiles, it is necessary to create the correct basis - the crate, therefore, it is necessary to begin the consideration of the process with the installation of this particular design department.
| Illustration | |
|---|---|
 | At the initial stage, of course, one of the types of truss systems is created, the design of which is described above. Before starting work on the installation of the batten on the rafters, the elements of the system must be additionally checked for their evenness and correct geometry. If irregularities are found on one of the rafter legs, then it must be leveled, since this flaw may adversely affect further work. The check is carried out using a perfectly even beam and a building level. |
 | The next step along the entire cornice line, a metal cornice strip is nailed to the edges of the rafters, which will protect the ends of the rafters from moisture getting on them. Separate planks are laid and overlapped. |
 | Further, on top of the truss system, a vapor-permeable membrane is stretched and fixed with brackets. Its first canvas is laid from left to right on top of the cornice strip. |
 | The next strip of material is laid horizontally, overlapping 150 mm on the bottom sheet. The membrane is mounted with an inscription, which is applied to one of the surfaces, outward. Along the cornice edge, the canvas is additionally fixed on the cornice strip with the help of construction double-sided tape. |
 | The last top sheet should protrude above the ridge, as it bends onto the second roof slope. |
 | At the next stage, the vapor-permeable membrane is fixed from above to the rafter legs with counter rails. It should be taken into account that if the length of the slope is not more than 6000 mm, the thickness of the counter rail should be 24 mm, with a length of not more than 12000 mm - 28 mm, from 12000 mm - 40 mm. The counter rails should not reach the ridge rib by 120÷150 mm. |
 | Further, on the ridge at the top of the junction of the rafter legs, pieces of timber 150 ÷ 200 long and with a section of 50 × 50 mm are fixed. The space remaining between them will play the role of ventilation gaps. |
 | After that, the ridge is covered with a sheet of a vapor-permeable membrane, which should be on the slopes and go beyond the structure from the gables to a distance of 200 ÷ 250 mm. |
 | On top of the membrane, laid along the ridge, for its fixation, sections of the beam are fixed in continuation of the counter-rails. Their size should be equal to the distance from the end of the counter rail to the crest of the ridge. |
 | When forming the cornice overhang, a perforated mesh-plate is mounted on the ends of the counter-rails and on the cornice strip, designed to provide ventilation of the space formed under the roofing material and protect against the penetration of various insects into this gap. |
 | Further, brackets are fixed in the eaves of the counter-rails for mounting gutters on them. Each of them is fixed with two screws or nails. |
 | In order for the gutter to be laid into the brackets without problems, they must be installed exactly in line with the formation of a slope for free flow of water. To do this, craftsmen often install two extreme brackets with the necessary difference, then pull a cord between them, and, already focusing on it, fix the rest of the hooks. |
 | After installing the brackets, a hinged beam is nailed along the cornice edge of the counter-rails along the entire length of the slope eaves. It also becomes the starting beam of the crate under the tiles. |
 | From the hinged beam on the extreme (at gables or roof profile fractures) counter-rails of the slope, the distance (step) with which the battens of the crate will be fixed is marked. This step will depend on the length and overlap of the particular shingle model. Most often it varies from 340 mm to 370 mm. Marking must be done on the extreme counter-rails. Then, on the marked risks, a nail is hammered in, a tracer colored cord is fixed and pulled on them, and with the help of it, a common line is beaten off on all counter-rails to secure the battens of the crate. |
 | The next step on the entire plane of the slope along the markings, horizontal battens of the crate are nailed to the counter-rails. Their cross-sectional size should be 70 × 30 or 70 × 25 mm. |
 | Upon completion of the installation, the crate should look like this. |
 | Next, it is necessary to prepare the roof ridge for further installation of ridge tiles on it - this can be done by attaching two beams to the ridge along the entire length, one on top of the other. |
 | Another option is to use special elements called ridge bar holders. They are screwed to the counter rails using two self-tapping screws on each side of the ridge. |
 | A wooden bar is installed and fixed in the fixed holders. Holders are convenient in that they can have different sizes and heights, so you can always choose it according to the required parameters. |
 | Further, a gutter is installed and fixed in the brackets along the entire length of the eaves. |
 | The gutter is additionally pressed by another cornice strip mounted on the eaves rail. This element, fixed along the entire length of the cornice, closes the entrance to the under-roof space, thereby protecting it from moisture, and descends into the gutter. |
 | Further, on top of the crate along the edges of the slope from the side of the gables, bars with a section of 70 × 70 mm are nailed. They will become the basis for fixing the wind board from the gable part of the roof, as well as limit and close the edge of the tiled masonry. |
 | After that, wind boards are installed and fixed along the pediment, which are additionally interconnected in the ridge area with a metal corner. On this, the preparation of the crate for the installation of a tile coating can be considered completed. |
Installation of tiles on the prepared crate
The installation of most models of ceramic tiles is almost identical, no matter what manufacturer's material is chosen by the owners.
| Illustration | Brief description of the operation to be performed |
|---|---|
 | Installation of tiles starts from the eaves on the right side of the slope. The corner tile is laid first, which is fixed to the second rail from the eaves. |
 | The first tile is fixed in the upper part with the help of two self-tapping screws that are not completely screwed in. |
 | Further, the entire first row of tiles is laid out, each of which is fixed in the upper part on the lathing rail with the help of one self-tapping screw through a hole drilled in it in advance. |
 | At the end of the first row of tiles, the last left corner tile is installed and screwed with two self-tapping screws. |
 | Further, from the bottom to the ridge, the first vertical gable row is mounted, consisting of corner tiles, each of which is fixed with two self-tapping screws. |
 | Next, you will need to prepare the tiles, which will be laid on top of the bracket for mounting a snow barrier on it. In order for the tile to neatly stand up and close the bracket, its location is marked on its reverse side and part of the lock is carefully knocked out with a hammer. |
 | Now, in the second horizontal row with a step of 900 mm, the brackets themselves are installed. This element is hooked with a hook and screwed to the third lath of the crate from the eaves. With the lower side, it is installed on top of the lower tile of the first row. |
 | Once installed and secured, the bracket should look like this illustration. |
 | Further, the prepared tile is installed on top of the fixed bracket and screwed to the third lath of the crate. |
 | The tile covering the bracket is additionally fixed with a wire hook, with which it is hooked to the side edge and twisted to the lath of the crate. In this way, every third tile of this row is fixed, which is laid on brackets-holders. In this illustration, a wire hook is clearly visible, located on the left edge of the tiles of the second row. |
 | Having installed the shingles of the second row, and having fixed all the brackets for the snow barrier, you need to try it on in place as it will be fixed later. It does not make sense to fix the barrier yet, as it will interfere with the further installation of the tiles. |
 | Further, laying of ordinary and corner tiles is overlapped, with their connection to locks, also from right to left, from bottom to top to those areas where additional elements necessary for the normal functioning of the roof structure are built into the coating. |
 | In this way, most often it is necessary to lay special ventilation tiles. If the roof has a length of up to 4500 mm, then these elements are not used. With a length of 4500 to 7000 mm, one row of ventilation tiles is mounted on the second row, counting from the ridge. On longer roofs, ventilation tiles are installed in three rows with a spacing of 1500 mm between them. |
 | On the third or fourth row from the ridge, in the middle part of the slope, a tile with a ventilation pipe, called a passage, is installed. |
 | In combination with other elements of the roof, this element looks like it is shown in this illustration. |
 | Having tried on this tile on a slope, it is temporarily removed, and a round hole is marked and cut out in the membrane under it. Then a sealing ring is installed in it. |
 | Further, from the attic side, a corrugated connecting pipe is inserted into the ring. Usually its diameter is 120 mm. Then, it is connected with the reverse side to the ventilation duct of the building. |
 | A protective cap is put on top of the ventilation pipe, which will protect the entire channel from atmospheric precipitation, dust and debris. |
 | Complete with tiles, a bench (step) for a chimney sweep is often purchased. This element of the roofing system is fixed on the fourth or fifth row from the ridge. The bench brackets are also of a hook design, and they are hooked and screwed to the top lath of the batten in the laying of the row. The lower side of the brackets is installed in the recesses on the tiles of the underlying row. |
 | In order for the closing brackets of the tiles of the upper row to fit snugly against the lath of the crate, chips are made in its locks located in the upper part after fitting. Then, the tiles are laid on top of the hook-brackets and fixed with screws and a wire hook - by analogy with what has already been discussed above. |
 | Another important and complex node when covering the roof is the design of the adjunction of the roofing material to the walls of the chimney. The joint between them must be sealed correctly and tightly. The most convenient way to work on the formation of the abutment is to use a flexible self-adhesive tape made using lead and aluminum. It well accepts a relief form of a tile and is well pasted to it. Adjacency finishing works are carried out in a certain sequence. First, the tape is glued to the front of the pipe with a call to its side walls, as well as to the tiles of the row passing in front of the chimney. To do this, in place, cuts of the desired shape are made on the tape. Then, it is measured and cut off, and then the tape is glued to the side walls and the tiles adjacent to them. |
 | To form a joint on the back side of the pipe, two pieces of tape of the same length are taken, which exceeds the width of the pipe by 20 ÷ 30 mm. They are glued to each other in width. Then, having combined the middle of the tape and the width of the pipe at a height of 150 ÷ 200 mm, the waterproofing is glued to the wall of the chimney and onto a metal sheet previously fixed to the crate on the upper side of the pipe. After that, on a tape glued to the metal, a row of tiles is laid on top. The parts of the tape protruding at the corners are cut, wrapped on the sides of the pipe, and overlapped on the waterproofing already fixed to them. |
 | Some craftsmen prefer to decorate the junction with sheet metal, which is cut into strips of the desired width, mounted according to the same principle as a self-adhesive waterproofing tape. The connection of the edges of the metal at the corners is carried out with the help of rivets and folding. |
 | Having fixed a waterproofing tape or a metal casing around the entire perimeter of the pipe, along its upper line on the pipe walls, a metal profile bar is fixed, pressing the flexible tape to the surfaces of the chimney. Then, the gap remaining between the upper edge of the plank and the wall of the chimney pipe is filled with a roofing sealant. Often a groove is cut through the wall of the pipe, into which the bent edge of this metal tide is inserted. Then the shtraba is sealed with the same sealant. |
 | Next, proceed to work on the ridge knot. First, a perforated sealing ventilation tape made using aluminum and lead is laid on the fixed ridge beam overlapping the top row of tiles. |
 | Thanks to its flexibility, this ribbon skirt perfectly adapts to the shape of the tiles without much effort. |
 | After the tape has been laid, the end ridge element is screwed from the pediment side of the ridge, and the first ridge tile is tried on to it. |
 | Further, the first tile is removed, and a ridge clamp with a bracket, which comes with the ridge tile, is screwed to the beam fixed on the roof ridge. |
 | Then the first ridge tile is installed in it. Further, it is fastened on the other side with the next clamp using a self-tapping screw. |
  | The next step is to install the second tile into the fixed bracket, which is also fixed at the end with a clamp - and so on, until the ridge is fully formed. |
 | When finished, the roof ridge should look like this illustration. |
 | The final stage in the design of the ridge is the fixing of the second end element. If necessary, the last tile of this row is cut to the desired size. |
 | When all the additional elements of the roofing are installed, the last step to the brackets installed at the bottom of the slope is to fix the lattice barrier that holds back the sliding of snow. |
 | This illustration shows a view of the finished roof slab as viewed from the eaves side. |
 | This is how the roof slope will look with all the elements installed on it. |
After completing the roof covering, you can move to the attic to remove the temporary flooring and lay the already stationary wooden floor. Installation begins to be carried out from the side of the attic or from the side of the room. The attic floor also consists of several layers and is arranged in different ways. The main thing is that if the roof is arranged, then work can be carried out slowly, without fear of precipitation on permeable materials and inside the premises.
In conclusion, it is worth emphasizing once again that the construction of a roof is a laborious, responsible and rather dangerous process. Therefore, to carry out the installation of the entire roofing system, it is sometimes better to invite specialists who are professionally engaged in the construction of houses, arrangement and roofing.
The design of the roof and the choice of roofing material is determined at the design stage and depends on the design of the facade of the building and the roofing technology. The choice of the type of roof, materials for its installation, its design, slope depends on climatic conditions, operation, architectural requirements, the degree of capitalization of the building.
Roof - the upper enclosing structure of the building, which performs load-bearing, waterproofing and, with non-attic (combined) roofs and warm attics, heat-insulating functions.
Roof - the upper element of the roof (covering), which protects buildings from all types of atmospheric influences.
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The roof of the building consists of the following elements: inclined planes called slopes (1), which are based on rafters (2) and lathing (3). The lower ends of the rafter legs rest on the Mauerlat (4). The intersection of the slopes forms inclined (12) and horizontal ribs. The horizontal ribs are called the ridge (5). The intersection of the slopes, forming the incoming corners, create valleys and grooves (6). The edges of the roof above the walls of the building are called cornice overhangs (7) (located horizontally, protruding beyond the contour of the outer walls) or gable overhangs (11) (located obliquely). Water flows down the slopes to the wall gutters (8) and is discharged through the water intake funnels (9) into the downpipes (10) and further into the storm sewer. |
1) Cornice plank; 2) Lathing board; 3) Falling beam of the counter-lattice; 4) Waterproofing film; 5) Rafter leg; 6) Skate; 7) Sheets of metal tiles; 8) Sealer ridge; 9) Cap of the ridge; 10) Wind bar; 11) Drain pipe; 12) Pipe holder; 13) Drainage chute; 14) Chute holder; 15) Snow barrier; 16) Upper valley; 17) Lower valley; 18) Wall profile. |
Roof classification
Depending on the slope of the slopes, the roofs are pitched (more than 10%) and flat (up to 2.5%). In individual housing construction, as a rule, pitched and sloping roofs are used. In flat roofs, the formation of stagnant water on the roof is possible and, as a result, the appearance of leaks in these places. The advantage of flat roofs is the possibility of using them for various purposes. According to the constructive solution, roofs can be attic (separate) and non-attic (combined). Attic roofs are insulated or cold. In non-attic (combined) roofs, the load-bearing elements serve as the ceiling of the upper floor of the building. Non-attic roofs are ventilated, partially ventilated and non-ventilated. According to the operating conditions, roofs are exploited and non-exploited. The type of roof is mainly determined by its geometric shape and roofing material. Depending on the shape of the roof, they can be single-slope, gable, three-, four-slope, multi-slope (Fig. 2).
shed roof (Fig. 2, a) with its plane (slope) rests on load-bearing walls of different heights. This roof is most suitable for the construction of outbuildings.
Gable roof
(Fig. 2, b, c) consists of two planes-slopes, based on load-bearing walls of the same height. The space between the slopes, which has a triangular shape, is called tongs or gables. A variation of the gable roof is the attic.
If the roof consists of four triangular slopes converging at one upper point, then it is called tent
(Fig. 2d).
A roof formed by two trapezoidal slopes and two end triangular is called hip four-slope (Fig. 2, e). There are also gable hip ( half hip ) when the pediments are cut off (Fig. 2, f).
Gable roof of an industrial building with a longitudinal lantern (Fig. 2, g) differs from the gable roof of a residential building by a smaller slope of the slopes and a greater width and length.
vaulted roof (Fig. 2, h) in cross section it can be outlined by an arc of a circle or another geometric curve.
folded roof (Fig. 2, i) is formed from the connection of individual trapezoidal elements - folds.
domed roof (Fig. 2, j) in outline is a half ball with a continuous support on a cylindrical wall.
Multi-gable roof (Fig. 2, l) is formed from the connection of the slopes of the planes. It is arranged on houses with a complex polygonal shape of the plan. Such roofs have a greater number of valleys (inner corner) and ribs (protruding corners that form the intersection of the roof slopes), which requires high qualifications when performing roofing work.
Cross vault represents four closed arched vaults (Fig. 2, k).
spherical shell (Fig. 2, o) in outline it is a vault, resting at several points on the base. The space between the supports is usually used for translucent lamps.
spire roof (Fig. 2, n) consists of several steep triangles-slopes, connecting at the top.
Roof from oblique surfaces (Fig. 2, p) consists of several gentle planes, based on load-bearing walls, standing at different levels.
Flat roof (Fig. 2, p) rests on load-bearing walls that have the same height. Flat roofs are most widely used in both civil and industrial construction. Unlike pitched roofs, on flat roofs, piece and sheet materials are not used as roofing. Here, materials are needed that allow the installation of a continuous carpet (bitumen, bitumen-polymer and polymer materials, as well as mastics). This carpet must be elastic enough to perceive thermal and mechanical deformations of the roof base. As a base, use the surface of thermal insulation, load-bearing plates, screeds.
In individual construction, as a rule, roofs are used, shown in fig. 2, a, b, c, d, e, f. The intersections of the roof slopes form dihedral angles. If they are turned downwards, they are called grooves, or valleys, if upwards, then ribs. The upper rib, located horizontally, is called the ridge, and the lower part of the slope is called the overhang.
To remove rain and melt water, external drainpipes are installed, through which water is discharged to a certain place and leaves the site through drainage ditches into street ditches. The magnitude of the slope of the slope and the durability of the roof depend on the material of the roof, as well as on climatic conditions (table).
Pitched attic roofs should be operated in good condition of the roof, supporting structures of roofs, normal temperature and humidity conditions in attic spaces and timely repair of the coating.
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I - attic; II - attic floor; III - supporting structure; IV - roof; 1 - constant loads (dead weight); 2 - live loads (snow, operational loads); 3 - wind (pressure); 4 - wind (suction); 5 - impact of ambient temperatures; 6 - atmospheric moisture (precipitation, air humidity); 7 - chemically aggressive substances contained in the air; 8 - solar radiation; 9 - moisture contained in the air of the attic space. |
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1 - frame crossbar (beams, trusses); 2 - bearing element of the coating; 3 - vapor barrier; 4 - insulation; 5 - coupler; 6 - roof; 7 - protective layer. |
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a-g - for pitched roofs; d, e - for gable roofs; g - plan for the device of rafters; 1 - rafter leg; 2 - rack; 3 - brace; 4 - rafter beam; 5 - crossbar; 6 - spacer; 7 - top run; 8 - bed; 9 - diagonal leg; 10 - short rafter leg. |
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a - truss spans of 6 m or more; b - the same, 12 m; 1 - crossbar; 2 - sleeper; 3 - brace; 4 - block; 5 - beams; 6 - puff; 7 - grandmother; 8 - brace. |
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1 - puff; 2 - pendant, or headstock; 3 - rafter leg; 4 - suspended attic floor; 5 - brace; 6 - emergency bolt; 7 - nails; 8 - roofing; 9 - two overlays; 10 - bolts; 11 - bolt dowels. |
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a, b - non-ventilated; in - ventilated; 1 - protective layer; 2 - roll carpet; 3 - coupler; 4 - thermal insulation; 5 - vapor barrier; 6 - ventilated channel; 7 - supporting structure; 8 - finishing layer. |
Roof construction
Attic pitched roofs. The pitched attic roof consists of load-bearing structures and a roof. Between such a roof and an attic floor there is an attic used to accommodate ventilation ducts (boxes), pipe runs, etc. With significant slopes, attic spaces are often used for built-in premises. The height of the attic in the lowest places, for example, at the outer walls, should be at least 0.4 m to allow periodic inspection of the structures. In the winter, heat and moisture penetrate into the attic through the attic ceilings from the premises of the upper floor. The warmer the attic and the more thermally conductive the roofing material, the more condensation (hoarfrost) is formed. When the outside temperature rises, the condensate melts, causing rotting of wooden structures and corrosion of metal elements. Humidification of the attic can also occur as a result of the penetration of moist air from the stairwells, and therefore the density of the porch of doors and hatches leading to the attic is of great importance. A very important and effective measure against moistening the attic space is its ventilation. To do this, arrange ventilation holes under the eaves (supply holes) and in the ridge (exhaust holes), as well as dormer windows. The bearing part consists of rafters, trusses, purlins, panels and other elements. The load-bearing structures of pitched roofs can be made of reinforced concrete, steel, wood in the form of rafters, building trusses and large panels. The choice of roof structure depends on the size of the spans to be covered, the slope of the roof, as well as the requirements for durability, fire resistance and thermal properties (Fig. 3).
The most widespread are layered and hanging rafters.
Rafters (Fig. 4) consist of rafter legs, struts and racks. They rest with the lower ends of the rafter legs on the rafter bars - Mauerlats, and the upper ends on a horizontal beam, called the upper ridge run. The role of the Mauerlats is to create a convenient support for the lower ends of the rafters. The top run is supported by uprights mounted on internal supports. The distance between the posts carrying the ridge runs is taken equal to 3 - 5 m.
To increase the longitudinal rigidity of the rafter structures, longitudinal struts are placed at each rack. If the building has two rows of internal supports in the form of longitudinal main walls or pillars, columns and other elements, then two longitudinal runs are laid. Rafters are used in buildings with intermediate supports and spans up to 16 m in size.
Recently, prefabricated wooden layered rafters, prefabricated at the factory, have become widespread. A set of such rafters consists of separate structural elements and has an abbreviated name - rafter shield, truss truss. Perhaps such a device of layered rafters made of precast concrete. Roof trusses are used in the construction of roofs for buildings of considerable width that do not have internal supports. The construction truss consists of two truss legs connected by a puff, which perceive the horizontal component of the forces transmitted to the support (thrust). With truss spans of 6 m or more, a crossbar is cut in, and with a span of up to 12 m, a headstock and struts are installed, which increase rigidity and reduce the deflection of the rafter legs (Fig. 5).
Roof trusses for low-rise civil and rural construction are made of beams and boards. Sometimes elements that perceive tensile forces in the lower belt or racks are made of steel. Such farms are called metal-wood. With four-pitched or more complex roof shapes, diagonal sloping rafter legs are introduced, forming triangular-shaped slopes in plan, the so-called hips.
Laminated rafters are made of beams, boards and logs (see Fig. 4). The pitch of the rafters is taken depending on the material from which they are made, the type of roof and the section of the elements of the crate. In the manufacture of rafters from beams with a thickness of 180 - 200 mm, they are placed after 1.5 - 2 m, and from plates and boards - after 1 - 1.5 m. In buildings of considerable width, when the length of the rafter legs reaches 8 m, it is necessary to arrange intermediate supports on interior walls. Beds are laid along these walls, racks and struts are installed on them, and then a run is installed on which the rafter legs rest.
At the intersection of the roof slopes, the rafters are made of diagonal and short rafter legs (see race 4, g). To protect the roof from being blown away by the wind, part of the rafter legs is tied to crutches driven into the outer walls with wire twists. All rafter interfaces are fixed with nails, bolts, staples. Reinforced concrete layer systems consist of reinforced concrete panels supported at the top on a ridge reinforced concrete run, and at the bottom on the outer walls of the building. The ridge run is supported by pillars installed every 4 - 6 m. Large reinforced concrete panels are used for single-pitched and gable roofs. Shed roofs are arranged on ribbed panels measuring 6.4x1.2 m, laid with a slope of 5%, gable roofs - with a slope of 7 - 8%.
At present, complex multicomponent binders can be used for the manufacture of reinforced concrete foundations. Before laying the roof on the panels, a cement or asphalt screed is arranged. In the absence of intermediate supports in small spans of buildings up to 12 m, hanging rafters are used (Fig. 6). They are made from the same materials as the layered rafters, i.e. from beams, boards and logs. Hanging rafters consist of rafter legs and puffs. The upper ends of the rafter legs are connected with a slotted spike, and the lower ends are cut into a puff with a frontal notch and fastened with bolts.
Rough roofs. Non-attic roofs are divided into non-ventilated, partially ventilated and ventilated with outside air. Non-ventilated roofs are used in cases where the accumulation of moisture in the coating during operation is excluded. Such coatings can be made with thermal insulation combined with the supporting structure. The main elements of the combined roof are flooring, insulation, vapor barrier and roofing (Fig. 7).
The flooring is arranged from reinforced concrete large-sized slabs of various types. A vapor barrier layer in the form of one or two layers of roofing material or glassine on the mastic is provided to protect the thermal insulation from moisture from water vapor penetrating from the interior. As a heater, plate and bulk heat-insulating materials are used. A leveling layer (screed) of cement mortar is made on top of the thermal insulation. The roof is laid on the screed. It is made of rolled roofing materials in several layers. Stick them on cold or hot mastic. To protect the waterproofing carpet from damage, a protective layer is made in the form of mounds of sand or fine-grained gravel embedded in the top layer of mastic, or a layer of roofing material.
Non-ventilated roofs mounted from solid or multi-layer panels. Such panels manufactured in the factory are sealed with a sticker on the upper surface of the waterproofing carpet, and on the bottom and along the contour of the panel - by applying a layer of paint vapor barrier. Partially ventilated roofs have pores or channels in the panel material located in the upper thickness of the panel. Ventilated roofs have continuous air gaps that dry the coating in winter and protect it from overheating by the sun's rays in summer. The height of the air gap is 200 - 240 mm. Combined roof structure consists of several layers of materials (see Fig. 7):
- a load-bearing element, for example, a reinforced concrete slab, which is trimmed from below to the ceiling of the upper floor;
- vapor barrier from one or two layers of roofing material on mastic;
- insulation - slabs of cellular concrete or filling of expanded clay, slag and similar highly porous materials;
- roofing from rolled material, made of roofing material, roofing felt, etc.;
- a protective layer made of fine gravel or sifted slag embedded in the bitumen paint layer.
With a non-ventilated roof, a cement screed is arranged along the insulation. If the roof is not ventilated, the insulation screed is made of cement mortar. The roof fencing consists of struts and struts and looks like a vertical steel grating. Racks and struts have limbs at the bottom - paws with which they rest on the roof. The fences are fastened with capercaillie, driven into the roof sheathing through holes in the legs of the racks and struts. Parapets are arranged in the form of a solid stone wall with holes at the locations of drainpipes.
Regulatory requirements for modern roofs are contained in a large number of documents, and some of these documents are already obsolete, but, nevertheless, have not been canceled. Design should be carried out taking into account the instructions and restrictions of the current standards:
- SNiP 2.08.01-89, 1995 "Residential buildings";
- SNiP 2.08.02-89 "Public buildings and structures";
- SNiP 2.09.04-87 "Administrative and domestic buildings";
- SNiP 31-03-2001 "Industrial buildings" instead of SNiP 2.09.02-85*
- It is put into effect from January 1, 2002 by the decision of the Gosstroy of Russia dated March 19, 2001 N20;
- SNiP II-26-76 "Roofs" (a new version of this SNiP was developed in 1999, but has not yet been introduced);
- SNiP II-3-79*, 1996 "Construction heat engineering";
- SNiP 3.04.01-87 "Insulating and finishing coatings";
- SNiP 21-01-97 "Fire safety of buildings and structures".
The roof is one of the most important elements of any building. Without a roof, it is impossible to imagine any residential building.
Nevertheless, if you are going to build this most important element of the structure yourself, with your own hands, you need to know what the roof of the house consists of, its main elements and design features.
So what is a roof?
What is the roof of the house made of?
The design and main elements of the roof are:
rafters - structures that can withstand the entire load of the roof, attacking snow, pouring rain. Basically, they are made from beams of large section, made of high-quality wood, without defects.
Base - looks like a crate made of wood, and sometimes it is a solid structure, depending on the material used. It is on the base that the roof is further attached.
Roof
- part of the roof, located at the very top and protecting the building or structure from precipitation. It also consists of many of the following elements:
- Slopes - designed to drain accumulated precipitation from the roof;
- Skates - close the gaps where two slopes meet;
- Inclined ribs - are protruding corners in those places where the slopes are connected;
- Valley or special grooves - these are internal corners that are obtained between two slopes;
- Eaves overhang - part of the slope, lying in a horizontal plane, which extends beyond the boundary of the building;
- Frontal overhang - the inclined part of the slope, protruding beyond the walls;
- Drip - a slope element in the form of a bar that protects the walls of the building from moisture;
- Gutters for the accumulation and removal of precipitation - as a rule, this includes downpipes and special funnels.
Today, in low-rise construction, single-pitched and gable roofs are the most popular. The design of such roofs is quite simple for the construction of their own hands, does not require the involvement of special equipment for work.
About that, it was written earlier.
Roof covering materials can also be different:
Rolled - they are distinguished by a rather low price and easy, without any special intricacies, installation. The disadvantages include rapid destruction from the action of precipitation.
leafy - this is a metal tile, cardboard-bitumen sheets and slate.
Membrane coatings - are new. Their composition includes compounds of polymers and rubber. Such materials are "not afraid" of water, fire, pass steam and serve for a long time.
Sandwich panels
- consist of steel sheets with insulation between them. They tolerate temperature extremes very well, have a long service life. Very often used as roofing materials for various warehouses, office buildings, etc.
This device has a roof and its elements.
The roof consists of rafters, lathing and fencing, that is, the roof. Inclined surfaces are slopes and ribs. Horizontal parts: ridge, valley and groove. Gutters are sometimes used to organize runoff at the lower edge of the slope. The lower part of the slope between the groove and the edge is called the "descent".
The wooden frame of the roof consists of the following structural elements: mauerlats, rafters and lathing - (main and mandatory), tightening, rack and struts (auxiliary) (Fig. 33).
Rice. 33. Structural elements of the roof frame: 1 - Mauerlat; 2 - rafter leg; 3 - puff; 4 - rack; 5 - brace; 6 - crate.
Mauerlat (popular name "womb, mother") is a beam with a section of at least 10 x 10 cm or a log hewn from the underside. The purpose of the Mauerlat is to serve as a support for the rafters and evenly distribute the load on the outer walls. In chopped and cobbled structures, the role of the Mauerlat is usually performed by the upper crown of the log house, and the clamps are nailed to the second crown from the top.
On walls made of lightweight masonry, lightweight concrete, frame and panel walls, it is necessary to lay a continuous mauerlat along their entire length. If the walls are massive (made of brick or stone), then a piece of log or timber 0.5 m long must be placed under each rafter leg. In this case, the ends of the clamps are attached to metal hooks, which, when laying the walls, are sealed with 2-3 rows of bricks.
Rafters - the supporting frame of the roof
The basis of the roof is a rafter made of wooden beams, boards, bars.
Rafters are a supporting structure that takes on the weight of the roof, snow and wind pressure; therefore, the wood from which the rafters are made should not have any flaws: rot, wormholes, falling knots, cracks in the joint zones, cracks outside the joint zones with a depth of more than 0.25 of the timber thickness and a length of more than 0.25 of its length.
For the manufacture of rafters, softwood boards with a thickness of 40-60 mm or beams are required. Lumber must be well dried, without defects, with a minimum number of knots. You can also use logs, but they are much heavier.
Plank rafters are easy to assemble. In this case, all connections are made on nails with or without lining and inserts. Cuttings that weaken log and lumber structures are used here only to connect racks with a run and a bed in inclined rafters.
The cross section of the rafters depends on the following factors:
- the load created by the weight of the roof and snow;
- span size;
- step of the rafters;
- roof pitch.
The size of the section of the rafters is selected depending on their length and the distance between them (Table 2).
Table 2. The relationship between the length of the rafters, the thickness and the distance between them
The rafters can be fixed directly on the Mauerlat, but if you need to cover a large span, some basic elements of the frame will not be enough, then tightening, rack and struts (both individually and combined) come to the rescue.
However, in any roof structure there are two main components: enclosing (roof) and bearing (rafters), which are divided into layered and hanging.
Layered rafters are beams resembling floor elements, but installed not horizontally, but obliquely on supports of various heights. They are supported by two outer walls - at a shed roof, or the outer and inner walls - at a gable roof. One more feature should be noted: the rafter legs of the opposite roof slopes are not at all necessarily fastened in the same plane - they can rest on the ridge run alternately (Fig. 34).
Rice. 34. Layered rafters: 1 - rafter leg; 2 - crossbar; 3 - attic floor.
The ends of the rafters rest on the walls of the building, and the middle part - on the intermediate supports. Rafters are arranged if the distance between the supports does not exceed 6.5 m. The presence of an additional support allows you to increase the width covered by the layered rafters up to 12 m, and two supports - up to 15 m.
Hanging rafters rest only with their ends on the walls of the building (Fig. 35).
Rice. 35. Hanging rafters: 1 - Mauerlat; 2 - rafter leg; 3 - puff; 4 - headstock; 5 - brace.
Unlike layered ones, they transmit only vertical pressure to the Mauerlat. Hanging rafters are used when the roof span is 7–12 m and there are no additional supports. Hanging rafters are usually arranged in buildings with light walls, as well as in buildings where there are no internal load-bearing walls.
The main elements of hanging rafters are rafter legs and puffs of the lower belt.
In the case of choosing a roof structure with hanging rafters, all elements are rigidly connected, since they represent a single structure - a truss truss, based on two extreme supports. The rafter legs, due to the lack of an average support, rest against each other in the ridge. The consequence of this is that a significant horizontal pressure is created, called thrust. If the roof is not built correctly, the walls may even tip over. The task of damping the horizontal pressure is performed by the lower belt of the truss truss - tightening.
The choice of roof structure depends on the specific conditions. Figure 36 shows different truss structures depending on the size of the overlapped spans.
Rice. 36. Various designs of truss ceilings: a - with a span of up to 5 m; b, e - up to 8 m; c, f – up to 10 m; d - up to 6 m; 1 - rafter leg; 2 - Mauerlat; 3 - ridge run; 4 - bed; 5 - rack; 6 - overlap; 7 - puff; 8 - crossbar; 9 - grandmother.
Laminated rafters are simple in design and do not require the use of lifting mechanisms during installation. Trusses with hanging rafters can be assembled on the ground, but then there is the problem of lifting them onto the structure under construction. Although it is possible to mount trusses immediately on the house, using boardwalk and auxiliary braces, boards from boards.
In wooden block-beamed or chopped buildings, the rafter legs rest on the upper crowns (Fig. 37), in frame buildings - on the upper trim (Fig. 38).
Rice. 37. Supporting layered rafters in wooden cobbled or chopped buildings: 1 - spike; 2 - rafter leg.
Rice. 38. Supporting layered rafters in wooden frame buildings: 1 - floor beam; 2 - rafter leg.
In stone houses, Mauerlat is used as a support for rafter legs - bars 140–160 mm thick (Fig. 39).
Rice. 39. Supporting layered rafters in stone buildings: 1 - Mauerlat; 2 - rafter leg; 3 - puff; 4 - attic floor.
Mauerlat can be located along the entire length of the building or placed only under the rafter leg.
In the event that the rafter legs in the section have a small width, they may sag over time. To avoid this, it is necessary to use a special lattice consisting of a rack, struts and a crossbar.
For the manufacture of racks and struts, boards 150 mm wide and 25 mm thick or wooden plates obtained from logs, the diameter of which must be at least 130 mm, are used.
To fix the rafter leg, a puff is used. When sliding along the puff, the rafter end can violate its integrity. To prevent slipping, it is recommended to cut the rafter leg into a puff with a tooth, a spike, or both at the same time (Fig. 40).
Rice. 40. Connection of rafters with a tooth and a spike: 1 - rafter leg; 2 - puff; 3 - spike.
In addition, it is advisable to install the rafters at a distance of approximately 300–400 mm from the edge. In the process of cutting the leg into the end of the puff, it is required to move the tooth as far as possible.
In the event that reinforced fastening of the rafters is required, it is advisable to use a double tooth (Fig. 41).
Rice. 41. Connection of rafters with a double tooth: 1 - rafter leg; 2 - puff.
Most often, teeth of different sizes are used: the height of one tooth is 0.2 puff thickness, and the height of the other is 0.3. Previously, on the puff, it is necessary to make an emphasis and a spike, and on the rafter - an eyelet (for the first tooth). For the second tooth, one stop is enough.
For additional fastening of the rafters, clamps and bolts are used in puffs (Fig. 42).
Rice. 42. Connection of rafters with a bolt and a clamp: 1 - rafter leg; 2 - puff; 3 - bolt; 4 - clamp.
Bolts are used less frequently, as they weaken the cross section of the rafter legs and puffs.
The installation is completed with the construction of the roof frame ridge (Fig. 43), sheathing of the cornices (the free part of the rafters protruding beyond the wall level - usually by 40–50 cm), the erection of the gable walls and the fastening of the lathing from boards or bars.
Rice. 43. Ridge knot: a - simplified; b - complex: 1 - rafter leg; 2 - rack; 3 - brace; 4 - puff; 5 - bracket, 6 - bolt; 7 - coupler; 8 - scarf.
Clamps from a steel strip are attached to the Mauerlat and the run, which make up the ridge knot, with large nails or twists are made of wire with a diameter of 5–6 mm.
In order to connect a strut to a strut in a complex ridge knot, it is required to hollow out a socket in the strut, and cut a spike in the strut. To make the connection stronger, it is additionally strengthened with bolts and clamps.
The rafter legs are connected to the crossbar by cutting a frying pan half a tree. To make the connection strong, it is necessary to fix it with a bolt, dowel or bracket (Fig. 44).
Rice. 44. The connection of the crossbar and the rafter leg: 1 - rafter leg; 2 - crossbar; 3 - bracket.
The roof must protect the walls of the building from the harmful effects of rain and snow, so the eaves overhang must be at least 550 mm long (Fig. 45).
Rice. 45. Bevel of the roof: 1 - rafter leg; 2 - puff; 3 - bracket.
The ends of the rafter legs are attached to the wall as follows: a screed-harness is put on the rafter-puff assembly, which is tightened with the second end either on the beam of the attic floor or on a crutch driven into brick or masonry at a distance of about 30 cm from the upper edge of the wall.
A tie-harness is also called a twist, which is a piece of thick wire, preferably galvanized. In wooden chopped houses, instead of twisting, it is advisable to use an iron bracket. It is designed to connect the rafters with the second crown of the log house.
The reinforced concrete rafter legs of the layered rafters are attached at one end to the outer wall of the building, and at the other end to the prefabricated reinforced concrete run. The run is supported by brick columns.
Roof base
The base under the roof can be made in the form of a crate or a solid flooring. It serves to lay and maintain the roof. The crate can be continuous, but more often - with a certain step, the value of which depends on the roofing material. In the manufacture of the base, 2 basic requirements must be observed: all its elements must be tightly fixed to the supporting structures, and their joints above the rafters must be spaced apart.
Solid flooring is advisable to use in cases where it is planned to use flat asbestos-cement tiles or rolled material as a coating. Under the tiles, the flooring is made of boards, the distance between which should not exceed 10 mm. The boards are laid out in one layer. Roll roofing is arranged on a flat two-layer base, which consists of carefully fitted dry boards. A special lining made of RPP-300 or RPP-350 roofing felt is placed between the floorings, which is necessary for wind protection.
A crate with a certain pitch is used in cases where the coating is made of tiles, sheet steel, wood or corrugated asbestos-cement sheets. In this case, the crate is arranged from 50 x 50 mm bars. The distance between the bars should not exceed 200 mm.
The specified distance between boards or bars - purlins - must be strictly observed over the entire surface of the base. The widest of them must be placed under the joints of the roofing material, as well as at the ridge and cornice, and the thickest (15-35 mm thicker than others) at the cornice. The width of the base under the gutter should be at least 750-800 mm, and under the eaves with wall gutters - equal to the width of the overhang. In the ridges and on the edges of the roof, wooden bars are installed on the edge.
Roof structure
The roof is the topmost cover of the roof, which protects all the structural elements of the building from atmospheric precipitation and diverts water to the ground. Therefore, the main requirement for the roof is water tightness.
The roof can be made of various building materials: steel and asbestos-cement sheets, industrial roll and local building materials (clay straw, clay reed, etc.).
Roofing (roofing) consists of:
- inclined planes - slopes;
- inclined ribs;
- horizontal ribs - skate.
The places where the slopes cross at an incoming angle are called " valleys" and " grooves", and the edges of the roof that go beyond the building horizontally or obliquely - eaves and gable overhangs respectively.
Atmospheric water from the slopes is collected in wall gutters from which it enters funnels, then in drainpipes and finally in storm sewer.
Roof elements can be laid both longitudinally and transversely, connecting them to the castle(roofing steel sheets) or overlap(all other types of coatings).
According to the design of the roof are:
– single layer- from steel sheets, asbestos-cement tiles and sheets (VO, VU), from strip stamped seam tiles;
– multilayer- from rolled materials, flat strip tiles, tesa, shavings, shavings and shingles.
The number of layers in multi-layer roofs varies from 2 to 5 depending on the material chosen, they are more labor intensive and less economical.
If in multi-layer roofs each subsequent layer is laid in the transverse direction, then it must overlap the junction of the elements of the underlying layer. If it is laid in the longitudinal direction, then it completely covers the underlying layer with the overlap established by GOST.
roof slope
The slope of the roof helps to remove precipitation from the roof. It is expressed in degrees or percentages. As a rule, during the construction of buildings, their roofs are made flat with the same slope of the slopes.
The choice of material for coating and the method of removing atmospheric water from the roof of the building depend on the chosen slope of the roof - drainage, which can be organized (external or internal) or unorganized (external).
Outdoor organized drainage consists of gutters and external downspouts. It is recommended to be used in those climatic zones where the water in the external downpipes practically does not freeze.
Internal organized drainage consists of a water intake funnel, riser, outlet pipe and outlet. It can be used in all climatic zones.
At unorganized drain water flows down the entire length of the lower edge of the slope without any additional devices. This type of drainage is allowed in climatic zones with little rainfall.
You can choose the right material for coating and the type of drainage in accordance with the slope of the roof using a special chart (Fig. 46).
Rice. 46. Schedule for the choice of roofing material depending on the slope of the roof.
Direct arrows on the graph show the angle of the roof above the horizon line: on a semicircular scale, it is determined in degrees, and on a vertical scale, in percent. Arc arrows indicate the types of material that can be used for a given slope.
When constructing a roof, you can use table 3.
Table 3. Roof slope and relative value for each slope
roof insulation
An attic is a room that is located between the roof and the upper (attic) floor of the building. As a rule, it is used to install water tanks, lay heating pipes and place prefabricated ducts and ventilation chambers. Moisture accumulating in the attic penetrates from the lower floors and is removed using ventilation devices. We can say that the attic is an intermediate zone between the living space and the street.
In the event that it is used as a living space, there is no intermediate zone. Then the moisture formed as a result of breathing, bathing and cooking takes the form of an invisible vapor.
Due to the pressure difference between the indoor and outdoor spaces, steam is generated, which tends to escape through the roof elements. The amount of vapor in the indoor air is directly proportional to the air temperature in it. In other words, warm air contains much more vapor than cold air. When the room temperature drops, the air loses its ability to retain moisture, which settles in the form of water. This happens when water vapor from the inside penetrates into the lower layers of the roof, on which moisture settles.
To avoid this, it is necessary to close up places where the roof does not adhere tightly to the base, through which moisture from the room penetrates into the roof and contributes to its destruction. What can happen due to insufficient tightness of the vapor and waterproofing layers.
To prevent this from happening, their device should be carried out in compliance with all the rules.
For roofs with slopes, the following types of insulation are provided:
- between the rafters;
- on the rafters;
- under the rafters.
Most often, the first method of isolation is chosen (Fig. 47), due to its relative simplicity.
Rice. 47. Insulation between the rafters: a - with a gasket tape; b - with wooden sheathing and a protective layer; 1 - gasket tape; 2 - counterbars; 3 - crate; 4 - thermal insulation; 5 - waterproofing; 6 - tiles; 7 - ventilation ridge; 8 - wood paneling; 9 - protective layer.
With this method, not a single section of the roof remains without insulation. Protected are the joints of roofs with walls, with window frames, with a chimney, etc.
The ventilation space between the upper part of the thermal insulation and the waterproofing must be at least 2 cm. When pulling the waterproofing layer, it must be ensured that it does not sag. Sagging sections of this layer will create an obstacle to normal air ventilation. Mineral fiber can be used as a waterproofing layer, which tends to increase in volume by 10–30% when laid. Therefore, when installing insulation, it is required to reduce its consumption by the same amount. If the depth of the rafters is insufficient for laying insulation and does not allow room for ventilation, you can build them up with boards and beams.
Another way to free up the ventilation space is to divide the insulating layer into two parts. One half is laid between the rafters, and the other - above them.
One of the latest achievements of science can be attributed to insulating systems with diffusion gasket tape. As a result of their application, the need for space arrangement between thermal insulation and waterproofing is eliminated.
Rafter insulation (fig. 48) has a number of advantages.
Rice. 48. Insulation on the rafters: 1 - sheathing; 2 - protective layer; 3 - counterbars; 4 - thermal insulation.
First, it itself is not a conductor of heat. The insulating shell is located above the bearing part of the roof and protects it from the effects of atmospheric phenomena. In addition, with this type of insulation, the rafters in the room remain in sight, which gives the attic space a rustic feel.
The insulation under the rafters (Fig. 49) has the following advantage: it is made solid, no ventilation space is required. Mineral fiber panels are used for this type of insulation. Its disadvantage is the reduction of the cubic capacity of the attic.
Rice. 49. Insulation under the rafters: a - with a gasket tape; b - with sheathing and a protective layer.
In the event that the equipment of the attic space is carried out in a house that was built a long time ago, the condition of all roof elements should be checked.
Old rafters can be affected by insects. Moreover, at first glance, wooden rafters do not give the impression of being damaged. However, when sawing off a piece of wood, insect passages may appear.
Heavily damaged roof elements must be replaced, the rest must be sanitized with special compounds made on the basis of artificial resins. These measures will help ensure high-quality hydro- and thermal insulation of the roof.