Frame house: from floors to roof. Standard mistakes when building frame houses Do-it-yourself interfloor slab in a frame house

Floor and ceiling in frame house- these are horizontal surfaces that limit and enclose its internal volume. They are mounted on ceilings that are part of power frame Houses. And in this sense, the importance of overlaps is difficult to overestimate. Besides the fact that they close on themselves vertical walls, forming a single strong spatial structure, the floors provide rigidity to the floor and ceiling, as well as thermal insulation and noise protection of the entire house.

Both the structure of the floors and the materials used for them depend on their place and purpose in the house. In a frame house, there are three types of floors: floor, ceiling (attic) and interfloor.

The first task is to provide the necessary strength and rigidity of the floor. Ceilings support only ceiling decoration and a layer of insulation, sometimes very impressive.

The interfloor ceiling performs the functions of both floor and ceiling, being the carrier of the floor top floor and the lower ceiling.

The most unpleasant load on the structure in question is vertical. Therefore, the base of the floor is calculated based on the need to minimize vertical deflections.

In a frame house, the floors in the vast majority of cases are made of coniferous species wood such as pine, spruce or larch. The basis is the sexual lags or ceiling beams. It is they who take on all the loads of the floor, then transferring them to the upper or lower frames, as well as to the internal walls or foundation.

Floor beams can be processed with two or four edges round wood, timber or edge-mounted boards with a thickness of at least 80 mm. It is acceptable to replace thick boards with paired thinner ones, for example, 50 mm thick. The main thing is to firmly and reliably “sew” them together. A more complex, but advantageous option in terms of rigidity/price is a device made from box-shaped boards or I-beams.

Standard size load-bearing beams determined depending on the span, load and permissible deflection. This value is for reference, and if necessary, the corresponding tables can be easily found on the Internet. Typical design frame houses allows you to record the average load values, from which you can determine the cross-section of the support beams.

Thus, the load on the floors consists of a constant component - their own mass, as well as variable loads that appear during the operation of the house. Self-weight of one square meter of interfloor and floor coverings frame house depends on their design, the insulation and sound insulation used and usually amounts to 210-230 kg.

Own weight attic floors higher, since more insulating materials are used here. It can range from 260 to 300 kg. However, variable loads on attic floors are less and, as a rule, do not exceed 100 kg per square meter, whereas for interfloor ceilings this figure is twice as high.

In order to calculate the total load on the floor, it is necessary to add the constant and variable components. Taking into account the span length of the beams and their profile, we find the cross-sectional area using the table. The distance between the beams is determined in a similar way, which is usually from 0.5 to 1 m.

Floor beams are installed on the frame and secured either using metal corners, or are cut directly into the strapping beam (board). For interfloor and attic floors there is a requirement: beams must be installed only above the vertical posts of the wall frame.

If in this case the pitch of the floor beams does not coincide with the calculated one, the latter must be reduced to a value that is a multiple of the pitch of the frame racks.

Flooring and filing

After installing and securing the beams, a flooring (top) and a lining (bottom) are installed on them. Interfloor overlap
requires a lining that supports only its own weight, decorative ceiling elements, as well as light weight soundproofing material. Therefore, the requirements for load-bearing capacity are minimal. Almost any sheet material can be used as such a lining in a frame house, for example - ceiling plasterboard, which also significantly increases the fire resistance of the building.

The attic and floor lining must support a significantly greater weight of insulation and other elements of the floor structure. Therefore, it is made from tongue-and-groove boards 30 mm thick.

Another option is a rewind device. In the lower part of the floor beams, so-called cranial bars are packed on the sides along their entire length. Typically, a rail with a cross section of 30x50 mm is used for this purpose. And roll-over shields are already laid on them: boards or any sheet material that can withstand the weight of the insulator, for example, plywood. In this case, the entire load from the weight of the internal elements of the floor falls on the roll. And the only thing left to do is support the weight of the ceiling trim.

In a frame house, there are two types of flooring: running and rough. Walking flooring is used in the attic to allow movement around it. In addition, the running flooring is a finished plank floor. Both types are arranged by fastening boards either directly to beams (floor joists) or through elastic pads.

But they differ in the quality of installation: the running floor boards are held together, while the subfloor boards are nailed with a gap necessary for the movement of air from reverse side finished floor. In attics that are not planned to be used, you can do without a top flooring. Instead, so-called passage boards are laid along the emergency passage route.

"Stuffing" of the ceiling

Floors of any type have a similar structure. Glassine, roofing felt or simply plastic film are placed on the roll or directly on the hem. Insulating material is poured or laid on top. Naturally they fall asleep bulk insulation materials, such as expanded clay, furnace slag, perlite, etc. Sheet or roll insulation is laid: polystyrene foam, glass wool, etc.

Please note that only floor and attic floors need to be insulated, and interior floors are only soundproofed with acoustic mineral wool. Required quantity insulation is determined from tables depending on its type and average winter air temperature.

Helpful advice: after filling the insulation into the attic floor, it is recommended to pour it on top with sand-cement or lime mortar. This event will significantly slow down the destruction of the insulation and extend its service life.

Ensuring optimal operating conditions

Considering the importance of floors for ensuring the normal functioning of a frame house, it is necessary to create proper conditions for them to maintain strength characteristics throughout the entire life of the house. And the most important of external factors providing negative impact on wooden structures ceiling, is moisture.

Any overlap to a greater or lesser extent prevents the free movement of air containing water vapor. And under certain conditions (temperature changes, air humidity) wooden parts moisture condenses in the ceiling. In the absence of sufficient air movement, the wood remains wet for a long time, which is fraught with the following consequences.

Firstly, the tree absorbs moisture and swells, changing its linear dimensions. And this, in turn, creates increased stress in the structure. Several cycles of “swelling - drying” can lead to a loss of strength of the joints of the floor parts, which will make their operation difficult, if not impossible.

Secondly, wet cellulose is a very good environment for mold growth, which can destroy floor beams in 2-3 years. The problem of humidity is acute for floors, to a much lesser extent for attic floors, and is generally not relevant for interior floors.

Therefore, to ensure normal air circulation in the basement, it is recommended to install ventilation ducts or wells.

Wooden floors in rooms with high humidity(bathroom, toilet, kitchen, etc.). Here it is advisable to supplement the ceilings with a waterproofing layer. But it’s better to refuse the bottom hem, limiting yourself to one roll. On the one hand, this will improve air exchange, on the other hand, it will allow you to control the condition of the ceiling parts.

As you may have noticed, it is not so difficult to arrange a ceiling in a frame house. The main thing is to do everything right. And then you will not remember its existence while you live in the house.

Good afternoon, dear frame builders!

I didn’t find a similar topic by searching, so I decided to create it myself.
Often the question flashes on the forum, how to do, how to block the span some kind of length. Sometimes the questioner simply does not have enough experience, sometimes some kind of hint or fresh thought is enough for him, sometimes he needs help choosing from several options, sometimes he needs to do an educational program and warn the person against dangerous mistakes. All this is scattered around different topics, and finding a problem like yours is quite difficult.
Let's help each other here on roofing issues, then it will be possible in one place to look at some kind of knowledge base and ask your question about covering a frame house.
Minimum information to ask a question:
1) House plan.
2) Span dimensions
3) What will happen at the top - what is the load on the floor
4) What is the difficulty with this overlap, what would you like and why it doesn’t work out.

I need help optimizing the flooring in a frame house.

Here is the main topic about my construction:
At this stage, the USP is done, I am drawing a frame design in SketchUp.

Here's the layout:

So far the frame of the 1st floor has been pre-rendered:

The pitch of the studs is 500 (optimized for OSB, since the insulation is ecowool, inside there will be plasterboard along the horizontal lathing). Yes, and step 600 seems to me a bit too much for 1.5 storey building. I want it to be strong)
External wall posts are 150x40, internal walls are 100x40. I plan to sheathe OSB, so no miters.

Here is the design of a typical wall:

Maybe someone catches your eye, write.

The plan shows that the house has one problem area- living room, span 4900 mm. There is also an opening for the stairs in this room, size 1100x2350 mm.

Task: To make a ceiling for the first floor, taking into account that there will be a residential attic above, and there will be 40mm screeds on the floor.

Due to my limited experience in designing such structures, I was unable to solve this problem quickly. More precisely, it turned out, and most likely it will work, but I feel that this is not very best option with a huge waste of material:

In the sketch, red lines indicate the walls, blue lines indicate the beams, and the yellow square is the supporting pillar that holds the staircase landing and supports the ceiling.

Beam spacing is 400 mm, beam size is 50x250.
This step and size (according to the calculator) is needed for overlap long span in the living room.
But, it is redundant on other spans.
And, although a supply might not be out of place, it is difficult to find logs of this size to cut 50x250 boards in such quantities (at least in our region). And I didn’t want to throw money away if I could do it cheaper and the result would be good.

What exits do I see:
1) Reformat the entire floor, radically changing the direction of the beams, their sections and pitch, possibly adding additional load-bearing elements. Here I need your help, because I don’t have a good option in my head yet.
2) Change the pitch of the beams, adjusting it to the spans. Then the ends of the beams will not meet so beautifully in the middle of the house, they will overlap and burst apart with breeches.
3) Change the height of the beams. Then it is not clear how to make the floor on the second floor the same height. In principle, you can replace some of the beams with 200-size beams, and place a 50 mm thick board flat in the places of support in order to reach the same height as the 250-size beams. Then the breeches will be sewn up beautifully.
4) maybe there is another option?

Thanks in advance to everyone who cares

It is its most important element.

Its main purpose is to divide the building into floors and ensure its high degree of stability.

The interfloor covering includes the main support beam, floor frame and flooring. The interfloor flooring becomes a subfloor, ready for finishing.

Some design requirements

There are various requirements, but the main ones are the following:

1. The structure must have a high degree of strength, since the load on the floor is significant. This is otherwise called the load-bearing capacity of the structure.
2. The ceiling must be sufficiently rigid; during operation, the ceiling must not sag under the weight of people and furniture.
3. High degree, due to which extraneous sounds and noise do not penetrate into the premises of the upper and lower floors.
4. Good thermal insulation of the ceiling is especially important when rooms with large temperature differences are separated.
5. The fire resistance of the ceiling is of great importance for the operation of a frame house. Special fire safety standards have been created that should be taken into account during the construction of interfloor ceilings.
6. Cost-effectiveness also plays an important role, which lies in the fact that the ceilings should be of small volume, not thick and not too heavy.

There are two options for creating interfloor ceilings:

• the overlap will be part of rafter system frame house;
• the ceiling will be a single platform, on the surface of which an attic or second floor of a frame house will be created.

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Features of such devices

Beam design interfloor ceiling along wooden beams: a-sections; b-prefabricated shield roll; c-prefabricated panel roll from a continuous row of longitudinal boards with boards or slabs nailed to them in the transverse direction: 1 clean floor; 2 lathing; 3 logs every 7-8 cm; 4 calcined sand or thermal insulation boards; 5 clay grease up to 2 cm thick; 6 bars; 7 prefabricated panel roll 5 cm thick; 8 plaster over shingles or over wire mesh; 9 strips; 10- croakers; 11 nails.

The interfloor platform of a frame house is built from the same materials and using the same methods as the lower floor platform. If the frame walls of the house were made perfectly straight, then this stage of construction will be completed without any special difficulties and very quickly.

Since the structure forms the frame of the upper floor and provides it with special strength, it is necessary to reinforce the joists, which will become the support for the internal frame walls.

For this purpose, multi-component beams are used. After the interfloor joists are installed, they proceed to dismantling the boards and spacers that were used to level the walls of the frame house.

You should pay attention to the fact that you should not be afraid that after the frame house is completely assembled, it may sway under gusts of wind. The defect will be completely eliminated after the house cladding is completed.

Sometimes the design of a frame house is created in such a way that the floor joists must be included in the rafter system. In this case, the following negative aspects may arise:

Interfloor floor structure: 1. Chipboard; 2. Frame; 3. Stone wool insulation; 4. Vapor barrier; 5. Lathing; 6. Stone wool; 7. Drywall or decorative board.

• the thermal insulation layer along the outer perimeter of the frame house may be significantly reduced, which, in turn, will lead to the formation of cold bridges;
• it will be necessary to think over a ventilation system for the under-roof space where there is a connection between floor joists and rafters;
• At the time of construction of the rafter system, temporary flooring is installed from sheets of plywood or boards.

Choosing building material for interfloor slab joists, the operating features of the room located above the slab should be taken into account. If this is an unheated non-residential attic, then you can use boards of small cross-section. For a residential attic space or full floor the logs must be of the same section as the boards of the lower room.

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Load-bearing floor beams (beam floor): 1 bottom frame; 2 extreme beam; 3 wall beam; 4 intermediate beam; 5 strip concrete foundation.

Interfloor ceilings for a frame house are made on a frame that is installed horizontally and attached to it with nails. If in wooden house If a large span is planned, then it is best to use glued beams.

1. can serve as both a ceiling support and a floor joist. The structure being erected has a simple shape. Boards are laid on the beams, and bottom part covered with plasterboard. The thickness of the floor boards must be at least 1/20 of the length of the gap between the beams. The space between the wooden beams is filled with sound and heat insulating materials.
2. At the base of interfloor wooden floors there are beams that need to be supported on load-bearing walls frame house.
3. To make beams, a log is used, which is sawn into four parts 70-80 mm thick. For wooden interfloor ceilings, paired boards 50 mm thick can be used.
4. Wooden boards are connected to each other either with metal staples or nails. Wooden beams for floors are low cost, easy to install, have excellent thermal insulation properties, their service life can reach 50 years, after which they will require major repairs.

Mineral wool has a low degree of thermal conductivity and is a natural material.

Since beams are made of wood, which is a combustible material and is subject to the destructive effects of rot and fungus. To prevent unpleasant consequences, it is necessary to treat the material with various antiseptic and anti-foam agents.

Design beam floor impossible without sound and heat insulation. Great value for future operation of the house it has, which can be both internal and external.

The following materials are well suited for this purpose:

• mineral wool;
• perlite;
• slag;
• foam;
• dry sand;
• expanded clay;
• shavings, sawdust, tree leaves, straw and many others.

Most preferred thermal insulation material is mineral wool, which has a low degree of thermal conductivity and is a natural material.

Among other things, this insulation is very light, unlike other materials, it “breathes” and is very easy to install.

You can often hear the opinion that frame houses are one of the simplest, most rational and inexpensive types building structures. Based on this idea, many developers choose frame technologies for construction, thinking about savings and even the possibility of building a house on their own. Unfortunately, the idea of ​​simplicity and low cost of frame technologies applies only to those that do not correspond to any building regulations and the rules of buildings that are erected by guest workers and inexperienced DIY enthusiasts. However, the same can be said about building log houses from wood with your own hands.

Frame technologies indeed have many advantages, but only in cases where the house is erected by experienced builders from industrially produced components for frame house construction. An inexperienced or illiterate builder, working with frame technology, can make many more mistakes than when building a house from solid wood or stone materials. Where, when building a house from massive wall materials, only a few technological operations, frame technologies will require a much larger number of technological “passes”. At more operations, the risk of making mistakes, non-compliance with technology and improper use of materials increases significantly. Therefore, frame houses built without a project and the involvement of qualified specialists “at random” or on trust in guest workers may be short-lived and will soon require overhaul due to unsatisfactory consumer qualities (freezing, wet insulation, high heating costs, rotting structural elements, destruction like individual elements, and the entire structure as a whole). Unfortunately, in Russia the list of regulatory construction documentation for the design and construction of frame houses is significantly limited. Currently, the 2002 set of rules SP 31-105-2002 “Design and construction of energy-efficient single-apartment residential buildings with wooden frame", developed on the basis of outdated National Standards for housing construction Canada 1998.

In this article we will provide brief overview main mistakes and violations of frame house construction technology.

Construction without a project.

This is a universal “general” mistake when choosing any construction technology. However, it is in frame technology the cost of mistakes can be especially high and lead to cost overruns instead of savings, both due to the use of an excess amount of material (frame made of large-section timber) and the need for repairs due to insufficient sections of beams, a rare step of their installation, destruction of structural elements due to for unaccounted loads, incorrectly selected connection methods in nodes and fastening materials, biological destruction of wood due to impaired steam and moisture removal.

Wood construction " natural humidity».

Almost nowhere in civilized countries are houses built from raw wood, just as before in Rus' they never built houses from freshly cut tree trunks. SP 31-105-2002 clause 4.3.1 states: « Load-bearing structures(frame elements) of houses of this system are made from softwood lumber, dried and protected from moisture during storage.” Raw wood is only a semi-finished product for the production of building materials. In Russia, sellers and suppliers delicately call raw lumber wood of “natural moisture.” Let us remind you that a freshly cut tree has a humidity of 50-100%. If the wood was rafted on water, then the humidity is 100% or more (the amount of water exceeds the amount of dry matter). “Natural moisture” usually means that the wood has dried out slightly during processing and transportation, and it contains between 30 and 80% moisture. When drying in the open air, the amount of moisture is reduced to 15-20%. Normal equilibrium moisture content of dried industrially wood in contact with the atmosphere will have a moisture content of 11-12%. When drying wet wood Lumber lengths are reduced by 3-7%, and wood volume by 11-17%. The use of “natural moisture” wood for the construction of frame houses leads to uncontrolled shrinkage of the wood, which changes the linear dimensions of structural elements and can lead to deformation, cracking and rupture of the wood with destruction of fasteners. When a wooden frame dries out, numerous cracks and gaps open up, significantly increasing the thermal conductivity of the walls of the frame house, tearing the insulating materials, preventing the penetration of moisture. When wood shrinks, its density increases, which leads to better conductivity of vibrations and sounds.

Construction from lumber without preliminary antiseptic treatment.

Even in the most properly designed frame house, loss is inevitable. a certain amount condensation on media sections, of which there is much more in frame houses than in buildings made of solid materials. A moistened tree containing polysaccharides in its structure is an excellent nutrient medium for various forms microflora and microfauna, representatives of which are capable of destroying the structure of a tree in short period time. SP 31-105-2002 (clause 4.3.2) states that all wooden elements located closer than 25 cm from ground level and all wooden elements not made of dry wood are subject to antiseptic treatment.

Incorrect use of materials.

In classical frame technology, the corner posts of the frame should not be made of timber or three boards knocked together closely - in this case, increased heat loss through the “cold corners” is ensured. The correct “warm corner” is assembled from three vertical racks, located in mutually perperdicular planes.

Materials that can bear loads are used to cover the frame. For example, OSB must be structural and intended specifically for outdoor use.

Insulation of vertical frame walls is permissible only with rigid insulation boards. Loose and roll insulation, due to shrinkage and slipping over time, can only be used for horizontal surfaces or on roofs with a slope of up to 1:5. When using economical versions of low-density insulation slabs, it is recommended to secure each row of slabs with spacers between the slabs to prevent slipping. This solution makes the structure more expensive and increases the thermal conductivity of the wall, so it is more profitable to use high-quality, more expensive insulation more high density. The size of the openings between the frame posts should not exceed cross dimension insulation slabs - 60 cm. It is even better if the size of the opening is reduced to 59 cm in order to eliminate gaps between the racks and insulation slabs. You cannot fill the walls with scraps of insulation - there will be many gaps.

Incorrect fastening of materials.

Black self-tapping screws can only be used for fastening sheet materials. The use of black self-tapping screws in a load-bearing frame, especially in a frame made of damp wood, can lead to the rupture of these unreliable fasteners that have low shear strength.

In all cases of assembling the load-bearing elements of the frame, galvanized nails or chrome-plated or brass-plated screws with a minimum diameter of 5 mm are used. Use of perforated steel fasteners without ligation wooden elements do not always guarantee the design strength of the frame.

Fastening elements of beams and other elements of the load-bearing frame must not be attached to OSB boards, especially with nails.
When nailing sheet elements with nails or screwing them with self-tapping screws, it is unacceptable to recess the cap or head deeper than the plane of the surface of the material. From the point of view of structural strength, the deepening of the head or cap by half the thickness of the material is considered a missing fastening element and must be duplicated with a correctly installed screw or nail.
Minimum distance from the edge of the covering material to the cap or head of the fastener is 10 mm.

Since 2012, the International building code for residential buildings (International building code, clause 2308.12.8) requires to prevent shifting during earthquakes, wind loads, etc. secure the frame of all newly erected frame buildings to the foundation with anchor bolts through pressure plates measuring at least 7.6 by 7.6 mm with a steel plate thickness of at least 5.8 mm. The minimum diameter of bolts or anchors is 12 mm.

Construction of frame houses using “innovative” technologies.

The most common frame construction technology in the world involves the sequential assembly of “platforms” - floors with floors, followed by the assembly of walls on them and their installation in vertical position. In this case, it is convenient for builders to move along a continuous surface, it is convenient to work with materials, any deviations from the design position can be eliminated before the construction of walls begins, and the floors themselves rest securely on the underlying structures. For some reason, domestic builders are trying to invent their own options for building a frame house with assembling walls “on site”, mixing the technology of building a frame house with the technology of half-timbering or “posts and beams” with the installation of floors last, which is fraught with the need for inserting or “hanging” floor beams, the need to move on temporary flooring, with a high probability of injury when falling from a height.

Errors in working with floor beams of a frame house.

Most mistakes are made with the fastening of beams. It is best to rest the beams on the top frame of the load-bearing walls, on the purlins. It is prohibited to reduce the cross-section of the beam by cutting down the cutout for joining with the trim. If it is necessary to connect the floor beam with the strapping beam or beam purlin, it must be secured through a backing support beam with nails, or using steel beam supports. The steel support of the beam must have a height equal to height beams and fastened with nails through all mounting holes. Fastening beams using smaller supports, not punching through all fastening holes, fastening with black self-tapping screws, fastening only with nails without a support bar are mistakes.

The most common spacing of floor beams in the world practice of frame house construction is from 30 to 40 cm. This spacing of beams allows you to obtain strong floors that do not sag under impact loads. The installation of floors with a pitch of more than 60 cm is generally not recommended. The minimum thickness of sheet materials for flooring on floor beams is 16 mm for a beam spacing of 40 cm.

Often beams-purlins that work in bending are assembled from boards flat, rather than installing them on an edge.

Load capacity floor coverage increases if the covering sheet material of the subfloors is additionally glued to the floor beams.
The load-bearing capacity of frame floors can be increased due to rigid transverse connections of the beams. Such connections are installed in increments of 120 cm and can serve as support for internal non-load-bearing partitions (through the subfloor). Also, transverse struts serve as an obstacle to the spread of flame during a fire.

How to properly drill holes in floor beams:

I-beams:

Composite I-beams can only be cut or drilled in certain locations per the manufacturer's specifications. The upper and lower elements of I-beams must not be disturbed. No more than 3 holes are allowed per beam. One hole with a diameter of up to 40 mm can be drilled in any part of the I-beam with the exception of the support parts. I-beams glued Wood-OSB-Wood are designated “Top”. At self-production beams based on OSB, the direction of the force axis of the material should be taken into account.

Floor beams made of sawn wood:

Errors in working with the cladding of a frame house.

According to foreign building codes and recommendations of the American Engineered Wood Association (APA), the frame can be sheathed with OSB boards both vertically and horizontally. However, if the OSB board is sewn along the frame posts, then the force axis (indicated on the OSB panel by arrows and the inscription Strength axis) will be parallel to the posts. This arrangement of the plates is useful only for strengthening weak frame struts that work in compression without significant lateral and tangential loads (which is almost unrealistic in real operating conditions). If OSB boards are sewn perpendicular to the racks, they strengthen the building frame to absorb tangential and lateral loads that arise when exposed to wind and base movements due to soil movement. Particularly relevant horizontal planking OSB panels in frames with missing bevels to impart the required structural rigidity. If OSB sheets are laid across the racks, then the force axis will be perpendicular to them, and the OSB sheets will withstand greater compressive and tensile loads. So, for example, in the domestic SP 31-105-2002. "Design and construction of energy-efficient single-family residential buildings with a wooden frame" provides (Table 10-4) the recommended parameters for the minimum thickness of plywood for cladding the frame: if the plywood fibers are parallel to the frame posts at a pitch of 60 cm, then minimum thickness plywood is 11 mm. If the plywood fibers are placed perpendicular to the posts, then thinner sheets with a thickness of 8 mm can be used. Therefore, it is preferable to sew OSB sheets with the long side not along, but across the racks or rafters. For the outer cladding of one-story frame houses, OSB 9 mm thick can be used. But when building two-story houses and any houses in zones strong winds The minimum thickness of OSB for external cladding is 12 mm. If a frame house is sheathed with soft fiber boards of the Isoplat type, then the frame structure must have jibs that provide lateral rigidity to the structure.

Between everyone sheet materials The sheathing should be left with gaps for thermal expansion of 2-3 mm. If this is not done, the sheets will “swell” as they expand.
Joining of sheathing sheets is carried out only on racks and cross members. The sheets are sewn “staggered” to ensure greater strength of the load-bearing frame structure using chain ligation. External cladding should connect the wall frame with the lower and upper trim.

« Pies" of the floors of the walls and roof of the frame house.

The main mistake in the design of frame pies for floors, walls and roofs is the possibility of the insulation getting wet from moisture penetrating inside. General rule building walls in heated rooms - the vapor permeability of materials should increase from inside to outside. Even in the floor, where they often do the opposite: a vapor barrier is laid on the ground side, and a vapor-permeable membrane on the room side.
Any insulated frame house pie must have a continuous layer of vapor barrier from the inside. “Continuous layer” really means that the vapor barrier should not have any defects: the sheets must be glued together with an overlap along the entire protected contour, without exception. For example, almost all builders at the stage of assembling the frame forget to lay a vapor barrier under the junction internal partitions To external walls according to standard connection diagrams of clause 7.2.12 SP 31-105-2002.

Additionally, all gaps between the sheet materials of the sheathing in wet areas and the roof must be taped waterproofing materials to prevent moisture from getting inside the insulated “pies”.
In addition to preventing moisture from entering the insulated cake, it is necessary to ensure that moisture is removed: from the outside frame wall must be either sheathed with OSB boards, which is a “smart” vapor-permeable material that can increase vapor permeability when the environment is humidified, or protected by a semi-permeable membrane that ensures the removal of moisture from the insulation. Cheap single-layer membranes have unsatisfactory vapor permeability and require an air gap between the insulation and the membrane. Also, cheap single-layer membranes provide poor protection against moisture penetration from the outside. It is preferable to use expensive superdiffusion membranes, which have really good vapor permeability and can be mounted directly over the insulation.

Ventilation of a frame house.

Figuratively speaking, the interior space of a properly built frame house is identical internal space thermos: heat loss through the walls is very small, and moisture transfer through the walls is most often practically absent (but may persist during use). Accordingly, it should be vented outside. Without a thoughtful one, this becomes impossible. In a frame house, each room must have ventilation valves, or the windows must have a micro-ventilation mode or built-in slot ventilation valves. Exhaust ventilation must be installed in the kitchen and bathroom. Abroad frame houses for permanent residence practically no one builds without supply and exhaust ventilation with a recovery system.

At the end of the article, we present illustrations of the widespread “folk” construction of a frame house, in which, upon closer examination, there is not a single correctly executed element.

The typical mistakes that we described in the article are easily preventable. Before you start building your first frame house or hiring builders, study in detail the albeit slightly outdated, but only set of rules available in Russian frame house construction SP 31-105-2002. By paying attention to all the details and subtleties of creating a power frame of a building and ensuring the durability of its operation, you can avoid costly mistakes when building or ordering your frame house.

The interfloor ceiling in a frame house is not only the basis for the floor or ceiling. It brings everything together vertical structures into a rigid unified system. Therefore, the installation of interfloor ceilings is no less important stage of construction than, for example, the construction.

Work order

After installing the board bottom trim begin the installation of interfloor ceilings on the first floor. Floor beams are made up of several smooth, high-quality boards or LVL beams are used.

Each beam rests on the concrete foundation wall by at least 100 mm. Its end is adjacent to the bottom trim board. The width of the niche for support should be 13 mm greater than the width of the beam. Niches for supporting beams are laid according to the project at the stage.

The floor joists rest on the floor beams. The distance between the lags depends on the platform sheathing material (subfloor). For example, if they are sheathed with plywood, the lag pitch is taken as a multiple of the size of the plywood slabs.

Eat constructive solution, in which the floor joists are adjacent to the end of the floor beam. In this case, they rest on an additional console nailed to the beam (Figure 1). Another option for attaching the logs to the end of the beam is using metal hangers (Figure 2).

For the manufacture of logs, only smooth boards are chosen. The use of small “sabers” is allowed. They are installed with an upward bend.

First, the joist is installed in the center of the span so that there are no shifts in the structure during installation. If the length of the log consists of two boards, the overlap at the junction must be at least 75 mm. The overlap is fixed with nails. The lag is attached to the beam and to the strapping board using nails.

When all the logs are installed and secured, check the accuracy of installation, the horizontalness of the surface so that there are no problems at the stage, and nail the outer perimeter board.

To strengthen the floor structure with composite joists, blocks are placed between them. They are made from scraps of boards, metal rods or wooden strips fastened crosswise. Wooden planks must be sawed down the right angle. Usually several types of blocks are made at once.

Then proceed to laying the subfloor made of plywood or osb boards thickness 15-21 mm. When using OSB boards with a special tongue-and-groove edge, it is not necessary to install blocks between the joists. Plywood without a special edge is nailed to joists and blocks. The plywood slabs are placed in a checkerboard pattern, with the long side across the floor joists.

On lateral surface The logs are carefully applied with glue. The slab is laid, being careful not to smear the glue on the joist. A gap of 2-3 mm is left between the plates so that it can expand freely as the humidity and air temperature in the room increases. The slabs are secured to the joists with wood screws or rough nails.

If the installation of the wall frame is postponed for some time, the subfloor slabs are protected from precipitation - either the plywood is treated with a special water-repellent compound, or the platform is covered plastic film so that the water flows to the ground.

Ceiling above the first floor

In a frame house, the ceiling above the first floor, in addition to its main function - to be part of the floor and ceiling - becomes an important stabilizing element. If the first floor has already been completed, then after installing the interfloor ceiling, you can remove the temporary jibs supporting the walls.

There is not much difference between the floor structures of different floors (1st and 2nd). They consist of the same structural elements. But in the interfloor ceiling of a frame house, LVL beams are more often used. After all, they can cover a long-span space without intermediate interior walls.

LVL beam consists of layers of softwood veneer glued with formaldehyde glue. It happens that from several standard beams, fastened with wood grouse, a beam is assembled that can withstand heavy loads. But even such a prefabricated beam can be installed by two or three people.

The beams are supported on external and internal load-bearing walls and secured with temporary jibs and nails. After installation of LVL beams, floor joists are installed from edged boards. They are attached with nails to the outer perimeter board and to the top trim of the load-bearing walls.

Depth of support on carrier wooden wall is at least 38 mm. The overlap between the joists, when resting on the internal wall, must be at least 75 mm.

The logs are placed above the frame racks of the internal walls. When attaching joists to the end of LVL beams, steel hangers are used (Figure 2).

If the house does not have a second floor or attic, then the ceiling of the 1st floor becomes part of the ceiling. Then the roof rafters are nailed to the ceiling joists. The frame is ready for roof construction.