Pitched roof is the distance between the rafters. Gable roof: rafter system for metal tiles

Before installation rafter system The question arises at what step to install the floor beams. Correctly calculating the distance between the rafters means preventing subsequent deformation or even destruction of the roof frame. After reading the article to the end, readers will learn what the distance between the rafters should be for different types of roofing and how to make the calculation correctly.

Even at the design stage of a wooden house, all load calculations must be made. This also applies to the rafter system. This is especially important in wooden house construction, since often the upper link is used instead of the Mauerlat. It is difficult to correct errors in such a design later. There is a technique for correctly calculating the distance between beams.

The span of the roof frame for the construction of a house made of timber typically exceeds 1 m, and the smallest valid value this is 60 cm, such indicators are indicated in GOSTs (see figure). You can correctly calculate the length of the rafters and their pitch using the following option:

Using a tape measure, the length of the roof slope is measured, the result is divided by the pitch size of the roof frame. For example, if the distance between the rafters is 1 m, then you need to divide by 1, if 70 cm, then by 0.7. The resulting figure is added to 1 and rounded to the nearest more. This way you can determine the number of beams for one roof slope.

You need to divide the length of the future slope by the result obtained. The result will be the distance between each rafter.

For example, consider a roof whose slope is 25.5 m and in increments of 0.6 m. You need to calculate the following indicators: 25.5:0.6=42.5, to 42.5+1=43.5. We round this figure to the nearest higher integer, we get 44. This is the number of rafter beams per 1 slope of the future roof.

Now we calculate the span between the rafters: 25.5:44 = 0.58 m. It turns out that you need to install the legs of the frame after 58 cm. This way you can easily calculate the pitch of any roof frame, single or complex, without taking into account the roof. But professionals recommend their calculations for a certain type of roof.

Rafter pitch depending on material

Since each forging material has its own characteristics and features. Among the most common are:

1. Profiled sheeting. Has different thickness and the shape of the tropezoidal bend. Costs from 120 rubles.
2. Ceramic tiles. Expensive material from 670 rubles. Has 12 color options.
3. Metal tiles. It's more cheap material unlike ceramic and costs from 320 rubles.
4. Ondulin. A soft roof insulates the house from rain, hail, etc. Costs from 340 rubles.
5. Slate. Most economical option from 90 rub.

We will consider the step size for the most common types of coverage below.

Spacing of rafter beams under corrugated sheeting

The distance between the roof beams depends on the size of the sheet that the corrugated sheet has. The pitch of the roof frame beams under the corrugated sheeting is standardly taken to be no less than 60 cm and no more than 90 cm.

If this distance is greater, then boards with a larger cross-section are attached between the rafter beams. The cross-section of the rafter legs under the corrugated sheet is selected 50x100 or 150 mm.

The most important thing to consider when planning to attach corrugated sheeting is the sheathing. It is made from boards with a cross-section of 30x100mm; it must be mounted with a span of 50 cm. It depends on the brand and thickness of the corrugated sheeting and the slope of the roof.

So, a 15º roof, grade C 10 corrugated sheeting is mounted on a continuous sheathing, C 21 corrugated sheeting is mounted on the sheathing with a span of 30 cm. The largest corrugated board C 44 is mounted on the sheathing in increments of 50 cm to 1 m. In this case, before attaching the sheathing, you need to consider the free space chimney passage, ventilation hood etc.

Spacing of rafter beams for ceramic tiles

The specifics of installing a rafter system for laying ceramic tiles are related to the weight of this roof. Ceramic tiles are made from clay, and this roofing weighs 9-10 times more than metal tiles. The calculation of the load on the rafter system for ceramic tiles is 40-60 kg/m2.

Beams for the roof rafter system for ceramic tiles are made only from dried material. The cross section is suitable 50x150 or 60x180 mm. The standard distance between the rafters for a tile roof is 80-120 cm. The span depends on the slope of the roof. At an angle of 15º, the span between the rafters is 80 cm, at 750 every 1 m 30 cm.

When calculating the step, you need to take into account the length of the beam. Taking maximum length the distance between the rafters is minimal. And, on the contrary, with a minimum length of rafters, the step is maximum.

When laying ceramic tiles, it is important to consider that you will need to walk on the roof. The maximum safe step of the rafter legs for such movement is 80 cm.

It is important when laying ceramic tiles to calculate the span of the sheathing. This distance is directly related to the size of the roofing material. A standard sheet of tiles is 40 cm long. Laying occurs with an overlap of 50 to 90 mm. When calculating the sheathing pitch, the overlap size is subtracted from the length of the tiles. The result is a pitch of 305-345 mm.

For pitched roof It is not difficult to make calculations for building a house from profiled timber. If the roof is complicated a lot pitched shape, then each distance between the rafters is calculated per lathing step separately. By securing the cord on the opposite side of the roof slope, you can easily mark the rows.

Features of the roof frame for metal tiles

Metal tiles are used more often than ceramic or corrugated sheets. Externally, the roof resembles ceramic tiles, but unlike it, it is easier to install and lighter.

Metal tiles weigh from 35 kg/m2 of roofing. This makes it possible to lighten the rafter structure and use beams of smaller cross-section. The step between the rafter legs of the roof frame increases and is equal to 60 to 90 cm. The beam is used with a section of 50x150 mm.

To create a ventilated space, holes with a diameter of 12-13 mm are drilled in the beams under the roof.

The design of the roof frame for metal tiles is not much different from corrugated sheets or ceramic tiles. But there is a small peculiarity: the support from above is attached to the ridge girder from above, and not from the side as in other cases. This will create a ventilated gap under the metal tiles, which will prevent the accumulation of condensation.

Features of rafter legs for ondulin

Ondulin is a soft roof used for the construction of a house made of laminated veneer lumber or other material. Ondulin is produced in the form of sheets; it looks like painted slate, but is lightweight. This material is great for wooden houses both low-rise and large.

Rafter beams under ondulin are placed with a distance of at least 60 cm, maximum 90 cm. For the rafter system, timber from coniferous species wood with a section of 50x150 or 50x200 mm. A smaller cross-section will not provide sufficient strength to the rafter purlins.

The sheathing on the rafters is made of material with a cross-section of 40x50 mm in increments of 60 cm. This is quite enough for fastening sheets of ondulin with an overlap of 30 cm. Ondulin is fastened with special nails, which are sold as a set.

Features of the slate rafter system

Slate is rarely used for roofing modern houses. But in dacha construction and household This material is irreplaceable in buildings. It is low cost and easy to install.

Slate rafters

Slate rafter legs are used with a section of 50x100 or 50x150 mm. The fastening spacing between the rafters is no less than 60 cm and no more than 80 cm.

The slate lathing is made from 50x50 mm bars or 30x100 mm wide boards. The sheathing is laid in steps depending on the slope of the roof. For a steep pitched roof it is 45 cm. The consumption is 4 bars per 1 sheet of slate. For gently sloping or gable roof 63-65 cm, so the consumption is reduced to 4 bars per sheet.

The pitch of the rafter system under slate differs in the roof structure. For households buildings are often installed with a single slope.

Feature of the size between the rafter beams on a single-pitched and gable roof

Whether a safety margin is needed during installation depends on the shape of the roof. And the distance between the rafter beams directly depends on this.

Single-pitch rafter system

A pitched roof is more durable and easier to assemble. The thickness of the rafters is selected depending on the type of wood, its strength and the specifics of a particular structure. The step between them can be 60-140 cm. The distance also takes into account whether the structure will be insulated. If yes, then the step should correspond to the width of the insulation.

The thickness of the rafter beams must be calculated depending on the roof slope. For a slight slope of 15-20º, you can use material with a cross section of 50x100 mm. For a steep slope of 45º, stronger ones with a section of 50x150 mm are needed.

Gable rafter system

If you do not calculate the pitch of the frame of a pitched or other type of roof correctly, the roof may move away, and the beams will sag and bend due to the weight of the structure. In that case simple repairs If you can't do it, you'll have to redo the entire structure. Therefore, it is so important to correctly calculate the distance between the legs of the rafters, depending on the roofing material used: corrugated sheets, ceramic or metal tiles, ondulin or slate, etc.

The roofs of modern private houses can have different configurations. The most popular type of roofing is gable. The undoubted advantages of such a roof are the owners suburban areas They consider reliability, quite attractive appearance and efficiency. The design of this type of roof is extremely simple, and therefore it will not be difficult to erect it, even with your own hands.

Light and durable sheet materials are what is most often used to cover a gable roof. Corrugated sheeting, for example, is simply ideal for such a design. This type of roofing protects the interior of the house well, lasts a long time and is inexpensive. Of course, the procedure for constructing a rafter system under corrugated sheets, like under any other material, has some of its own characteristics.

Where to start

How is a gable roof assembled? under the corrugated sheeting it will turn out to be reliable, and the roof itself will be neat only if a detailed design design is drawn up first. When developing the latter you need:

determine the angle of inclination of the slopes;

decide on the type of materials needed for construction;

make detailed drawings of the frame indicating the method of connecting all nodes.

If all these operations are completed without errors, the end result will be a strong gable roof. A rafter system for corrugated sheets, a drawing of which can be made using, for example, special software on a computer, will last as long as possible.

Load calculation

This step should never be skipped when drawing up a roof project. Correctly performed calculations are the key to the end result being a durable gable roof. The rafter system for corrugated sheeting (a photo of the assembly of such a frame can be seen below) is mounted taking into account the following parameters:

weights of all materials used;

The values ​​of the last two indicators can be found in special tables developed specifically for each specific region.

All figures obtained as a result of calculations must be added and multiplied by a reliability factor of 1.1. After calculating the rafter system gable roof Thus, it will be possible to determine, first of all, the type of materials needed for assembly. Also, taking into account the final load indicator, the optimal angle for the roof frame supports is selected.

Slope angle

In addition to the load, when choosing this indicator, the characteristics of the roofing material itself should also be taken into account. The angle of inclination of the slopes can be any, but not less than 12 degrees. If you make the roof flatter, it will leak later. At the same time, the sheets themselves will begin to sag under the weight of snow in winter. That is, the roof will have to be constantly repaired. And this, of course, is additional costs.

IN Middle lane In Russia, taking into account wind and snow loads, it is almost universally allowed to erect roofs with slope angles of 30-45 degrees. This option is ideal for corrugated sheets. In the southern regions, the angle of inclination of the slopes of the roofs of houses may be smaller, and in the northern regions, on the contrary, it can be greater.

Among other things, when choosing a method for installing rafters, it is worth considering exactly how the attic will be used in the future. If it is intended to be insulated and equipped as a living space, it is better to make the slopes steeper. But of course, in this case, erecting a roof will cost a little more, since you will have to use more materials.

What to build from

What specific materials can such a gable roof be constructed from? with your own hands - in any case, it is a responsible matter, and must, of course, be as reliable as possible. But one of the advantages of corrugated sheeting is that it is light in weight. Therefore, it is not necessary to use any special, very durable materials to assemble the frame for it. This type of roof is quite suitable for rafters standard timber 150x100 mm. It is advisable to use lumber of a larger cross-section only if the attic is intended to be used as a living space. Rafters for such a roof are usually made of 200x100 mm timber.

The sheathing can be assembled from edged boards 30x100-150 mm. Too wide lumber cannot be used in this case. After some time, such boards will simply dry out and become severely warped, which will have an extremely negative impact on the reliability of the roof. Under the Mauerlat it is better to take a thicker beam - 200x150 mm.

Step between structural elements

Too often, it is also not necessary to install frame supports under light metal sheets. Optimal distance between the rafters of a gable roof under the corrugated sheeting is 60-80 cm. As for the sheathing, the pitch between its elements is selected taking into account the type of sheets used. So, for thick material 0.6-0.7 mm with a profile height of 3.5 cm, boards can be stacked at a distance of up to 1.5 m from each other.

For standard N-grade corrugated sheeting, the lathing pitch is usually 60-70 cm. The same distance is suitable for CH material. Thin sheet C is mounted on a sheathing, stuffed in increments of 10 cm or on a continuous sheet of 12 mm plywood or OSB sheets.

How to assemble a gable roof. Rafter system for corrugated sheets

The roof frame of the house is mounted in several steps:

Mauerlat is installed;

rafters are installed;

if necessary, insulation is installed;

the rafters are covered with waterproofing;

the sheathing is stuffed.

Mauerlat installation

They begin assembling such a structure as a gable roof made of corrugated sheets with their own hands by installing this particular element. The Mauerlat is mounted on top of the building frame. As a basis for the rafter system, this element is used only on brick, monolithic or block walls. In cobblestone and chopped ones, its role is played by the upper crown. The timber should be secured to the walls using anchor bolts. You can also use steel dowels, galvanized wire with a thickness of 5 mm or staples.



Methods of fastening rafters

The supports themselves can be attached to the Mauerlat in two ways. For brick, block and monolithic houses Rigid fixation technology is used. In this case, they are attached to the Mauerlat using galvanized steel corners and self-tapping screws or with a “knot” of three nails (one in the upper plane, two on the sides).

On chopped and cobblestone walls, the rafters are fastened using the sliding method. The fact is that such houses shrink strongly during the first time after construction. Therefore, a rigidly fixed roof frame can simply fail in the future. With the sliding method of installing rafters, special fixing elements, “sleds”, are used, ensuring the mobility of the supports in a small range.

How to install

The supporting elements of the frame must be installed correctly. In this case, you will get a neat symmetrical gable roof. The rafter system for corrugated sheeting, like for any other material, must be assembled using a template. In this case, all legs will have the same length. For gable roofs made of corrugated sheets, either simple straight rafters (with the edge cut at the required angle) or an option with mounting sockets for the Mauerlat can be used. The frame supports are usually attached to each other at the top using special thick steel plates.

The end trusses are always installed first. Next, a cord is stretched between their highest points. Then, focusing on it, intermediate trusses are installed. On large roofs, a ridge girder on supports is pre-installed between the outer paired rafters. The latter are securely fixed to the floor beams.

Installation of insulation and waterproofing

If the attic is intended to be made habitable, it will, of course, have to be insulated during the construction of the roof. On corrugated roofs, it is most often used for this purpose. mineral wool. To support it, a wire is stretched from the attic side onto the rafters. The mats themselves are installed by surprise.

The waterproofing is sewn onto the rafters with a slight sag (2 cm). Do not stretch the film too much. Otherwise, when the frame moves, it may simply tear. The waterproofing strips are installed horizontally from bottom to top with an overlap of at least 10-15 cm.



Installation of sheathing

The support boards under the corrugated sheets are attached to the rafters using nails with a diameter of about 3-3.5 mm. The length of the fasteners must be twice as long as the thickness of the elements being fixed. Assembly begins from the cornice. The boards should be fastened to each rafter with two nails. The last two rows at the ridge are filled without a gap.

After the sheathing has been assembled, you can begin covering the frame with the corrugated sheet itself. At the final stage, the roof gables are covered with boards.

What you need to know

Wood is a material that is very easy to process and at the same time quite durable. That is why the rafter system of a gable roof is most often assembled with your own hands from timber and boards. However, unfortunately, lumber cannot boast of a very long service life. Sooner or later, the roof of the building begins to dry out or rot. Therefore, before assembling it, the timber and boards must be processed special compounds, increasing their moisture resistance.

Another disadvantage of wood is flammability. To reduce the risk of fire to a minimum, the lumber used to construct the building frame should, among other things, be carefully treated with a product that increases their fire resistance.



This is how the gable roof is assembled. The rafter system under the corrugated sheet, as you can see, is mounted simply. Nevertheless, installing a roof frame is a very responsible undertaking. If any technology is violated, the owners of the house will inevitably have problems with leaks and the need for replacement. individual elements etc. Therefore, it is worth approaching the assembly of the roof truss system with maximum responsibility.

The task of correctly calculating the distance between the rafters is a very important one. How seriously you begin to solve it will determine not only the reliability and durability of the roof, but also all subsequent work on it: laying insulation, installation roofing, installation of additional elements. If you manipulate the pitch of the rafters under the roofing sheets, as many do, then it is not a fact that insulation will then fit between the rafters.

If you focus only on insulation, the very first winter with its abundant Russian snow will crush the rafter system. That's why the whole point is to pick optimal step rafters for all slopes, and this is the skill we will teach you now.

What determines the pitch of the rafters?

So, the distance between the rafters is determined by the following important factors:

1. Roof shape (gable, single-slope or multi-slope).
2. Roof angle.
3. Parameters of the timber used to make rafters (width, thickness).
4. The design of the rafter system (sloping, hanging or sliding).
5. The totality of all loads on the roof (weight of covering, atmospheric phenomena, etc.).
6. Lathing material (20x100 or 50x50) and its parameters (solid, with gaps of 10 cm, 20 cm or solid plywood)

And each of these parameters needs to be taken into account, which is exactly what this article is about.

Online calculators vs. notepad and pencil

To correctly calculate the cross-section of rafters and the pitch of their installation, today there are many complex formulas. But remember that such formulas were at one time developed more so that it would be possible not so much to perfectly calculate roof structures, but to study the operation of such elements.

For example, today simple online programs are popular that do a good job of calculating rafter parameters. But it’s ideal if you can install it yourself specific tasks and calculate everything you need. It is important to understand down to the smallest detail what exactly happens in the rafter system during operation, what exact forces are exerted on it and what loads. But a computer program cannot always take into account everything that the human brain notices. Therefore, we advise you to make all calculations manually.

Decorative rafters: 0% load

First of all, decide on the most important point: the type of roof and its purpose. The fact is that the roof of a residential building in winter can withstand a large cap of snow, a constant wind at height, and it is also often insulated from the inside, but to the rafter system small gazebo, hidden under the canopy of trees, have completely different requirements.

For example, if you are building a pergola in its classical sense, then it does not matter at all what exactly the distance between the rafters will be - this is a purely aesthetic factor:

The illustration above shows that even such a building has its own pitch of rafters. After all, here it provides both the aesthetic factor and the rigidity of the structure itself. But they choose a step arbitrarily.

We come to the main question: what distance should be between the rafters of the roof of a residential building? Here, be patient and carefully study all the nuances.

Point 1. Wall length and choice of rafter spacing

The first step in installing rafters on the roof of a residential building is usually chosen structurally based on the size of the building, although taking into account many other factors.

For example, the easiest way is to install rafters in 1-meter increments, so for a wall 6 meters long, 7 rafters are installed as a standard. At the same time, you can save money by placing them at a distance of 1 and 2 meters, and you will get exactly 5 rafters. It can also be placed at a distance of 2 and 3 meters, but reinforced with lathing. But it is extremely undesirable to make the rafter spacing more than 2 meters.

Point 2. The influence of snow and wind loads on the shape of the roof

So, we settled on the fact that the average distance between the rafters regular roof– 1 meter. But, if there is a significant snow or wind load in the area, or the roof is more or less flat or simply heavy (for example, covered with clay tiles), then this distance must be reduced to 60-80 cm. But on a roof with a slope of more than 45 degrees it can be even increase to a distance of 1.2 m-1.4 m.

Why is this so important? Let's figure it out. The point is that air flow collides on its way with a wall under the roof of a building, and turbulence occurs there, after which the wind hits eaves overhang roofs. It turns out that the wind flow seems to bend around the slope of the roof, but at the same time trying to lift it. And at this moment forces arise in the roof that are ready to tear it off or overturn it - these are two windward sides and one lifting one.

There is another force that arises from wind pressure and acts perpendicular to the slope, trying to press the roof slope inward. And the greater the angle of inclination of the roof slope, the more important are the safe wind forces and the less tangential ones. And the greater the angle of the slope, the less often you need to install rafters.

This map of the average wind load will help you understand whether to make a high roof or a flat one:

Second point: in Russian region on standard roof at home is constantly exposed to atmospheric phenomena such as snow. Here too, you need to take into account that the snow bag usually accumulates more on one side of the roof than on the other.

That is why in places where such a bag is possible, it is necessary to insert paired rafter legs or make a continuous sheathing. The easiest way to identify such places is by the wind rose: single rafters are placed on the windward side, and paired rafters are placed on the leeward side.

If you are building a house for the first time, then you won’t have to decide on your own worldview, but rather determine the average snow load for your area according to official data:

Point 3. The issue of insulation and standard width of mats

If you will be insulating the roof, then it is advisable to place the pitch of the rafters under standard sizes insulation slabs, which are 60, 80 cm and 120 cm.

Modern insulation materials are sold today standard width, usually at the same standard rafter pitch. If you then take them and adjust them to existing parameters, then there will be a lot of waste, cracks, cold bridges and other problems.

Point 4. Quality and strength of the lumber used

It is also of great importance what kind of material you use to build the rafter system. So, for each type of wood there is its own regulatory documentation that concerns it bearing capacity:

Because For the manufacture of roof truss systems in Russia, pine and spruce are most often used; their bending strength and features of use have long been prescribed. If you use wood of other species, you can derive a correction factor.

In addition, if the rafters have sections, notches or holes for bolts, in this place the load-bearing capacity of the beam must be calculated with a coefficient of 0.80.

Point 5. Distance between tie rods and floor beams

One more point: if the roof is built with interconnected trusses, and their lower chord is used simultaneously as floor beams, then the distance between the trusses should be within 60-75 cm in order to take into account the design of the future floor.

Point 6. Loads on rafters

So, here are the main loads that act on the roof truss system:

1. Static, which includes the weight of the rafter system itself, the weight of the roof, the snow lying on the roof and additional elements.
2. Dynamic, which includes wind force, unexpected damage to the roof, the weight of a person and equipment for repairs, and similar factors.

And all these factors are capable of certain moment act on the roof at the same time, and therefore there is such a thing as critical value. This is exactly the load value at which the roof cannot withstand and becomes deformed.

Therefore, if a building is being built with significant spans, then steel roof trusses must be used. The fact is that there is no longer any tension in such rods, and the entire load falls on the nodes - here they are affected by compressive and tensile forces. And the distance between such trusses is calculated depending on the type of roof and the design of the roof itself.

Typically, a unified truss is installed with a span that is a multiple of six, and therefore a distance that is a multiple of one and a half meters is made between the nodes of the truss.

Point 7. Weight of the rafter system and roofing pie

Do not forget that the main purpose of the rafters is to support the entire roof, and its weight at the same time has crucial:

Point 8. Ease of installation of roofing

The distance between the rafters is also influenced by factors such as the selected roofing covering. The higher the roof slope, the more roofing materials will be used in this case. And the heavier they are, the more often you will have to put rafters under them. But what about the continuous sheathing? The fact of the matter is that it also has its own weight:

Each type of roof has its own optimal rafter pitch. After all, many standard sheets at the edges need to be fastened directly into the rafters or sheathing, and it is important that they coincide. Otherwise, the work of covering the roof will easily turn into a living hell at altitude, believe me.

That is why, even before starting installation, you must make a layout and check everything several times. And know some important subtleties for each type of coating.

Determination of the totality of loads on the roof as a whole and the rafters separately

So, we have determined that, in addition to other design factors, a whole set of loads simultaneously acts on the roof rafter system: the weight of the rafter system, the snow cap, wind pressure. After you add all the loads together, be sure to multiply them by a factor of 1.1. So you all plan for the unexpected favorable conditions, that is, to provide an additional 10% percentage strength.

Now all you have to do is divide the total load by the planned number of rafters and see if each of them can cope with its task. If it seems that the structure will be frail, feel free to add 1-2 rafters to the total, and you will have peace of mind for your home.

You need to make calculations for destruction, i.e. for the full load acting on the roof. All these loads are determined according to the technical characteristics of the materials and SNiPs.

The standard roof structure consists of rafters, lattice purlins, and each of these elements responds only to the load that puts pressure on it, and not on common roof generally. Those. Each individual rafter is subject to its own load, total, but divided by the number of rafter legs, and by changing the step of their location, you change the area where the load is collected on the rafters - reducing it or increasing it. And, if changing the pitch of the rafters is inconvenient for you, then work with the parameters of the cross-section of the rafter legs, and the overall load-bearing capacity of the roof will increase significantly:

When making this calculation, try to ensure that the longest rafter in your project is no more than six and a half meters, otherwise, splice along the length. Now let's explain in more detail. So, on roofs with slopes up to 30 degrees, the rafters have so-called “bending elements”. Those. they work specifically for bending, and there are certain requirements for them. And the possibility of rafter deflection is calculated using a special formula, and if the result exceeds the norm, then the rafters are increased in height and a new calculation is made again.

But on a roof with a warehouse slope of more than 30 degrees, which rafters are already considered “bending-compressed” elements. That is, they are affected not only by a uniformly distributed load, which causes the rafters to bend, but also by forces that are already acting along the axis of the rafters. Speaking in simple language, here the rafters not only bend a little under the weight of the roof, but are also compressed from the ridge to the mauerlat. In addition, the crossbar, which usually holds the two rafter legs, must also be checked for tension.

As you can see, even a person far from construction can handle such calculations. The main thing is to take everything into account, be attentive and ready to spend a little more time on design, so that then all the work goes like clockwork!

The rafter structure is the fundamental element of a pitched roof. Incorrectly calculated distance between rafters, incorrect consideration of the load on the erected system of beams, or their incorrect installation will most likely lead to deformation and collapse. The stability of the rafter system depends on:

1. from strength at the bottom to the ridge at the top;
2. validity of the rafter support drawing, taking into account the span length;
3. wood quality;
4. pitch of the rafters.

Obviously, the main condition for the reliability of a roof structure is a correctly calculated distance between the rafters. You can figure out how to determine this value for a pitched, gable, or hip roof.

What are the calculations of span lengths based on?

A competent design calculation, in which the pitch of all rafter legs is calculated according to the same principle for any type of roof, is based on the following indicators:

1. type of roofing material (metal tiles, slate, etc.);
2. distance (span) between adjacent supports;
3. the angle at which the rafter legs are attached.

• rafter weight;
• insulation weight;
• roof weight;
• sheathing weight;
• snow;
• wind;

the weight of a person or people who will subsequently be involved in repairs and maintenance of the roof itself and the objects located on it.

Snow and wind - the values ​​​​are different for each region, you need to look for these indicators in reference information specific locality or region.

How to calculate rafter spacing

The exact distance between the rafter legs is calculated using complex mathematical formulas, strength of materials, but many craftsmen cope with this task in their own way. After calculating the maximum load, the following actions should be taken:

• measure the length of the roof;
• divide the result obtained by the span of the roof frame or the approximate step for installing the rafters (the pitch of the rafters is the distance from one leg to the other of the rafter system, usually a standard value, approximately selected, is taken into account);
• add one to the result obtained, round the resulting value;

After this, the length of the roof slope should be divided by the resulting value (the number of rafter trusses) - the desired rafter pitch will be obtained.

Calculation example. The ramp is 27m long, the selected pitch is 0.8m.

27:0,8=33,75
33,75+1= 34,75
round up = 35, the number 35 means that you need to install 35 rafters.

We determine the distance between the rafters: 27: 35 = 0.8. That is, the leg is installed one from the other at a distance of 80 cm.

The generally accepted standard is a value equal to 1 meter, and a step of eighty, seventy, ninety cm may also be optimal. Obviously, the calculation procedure cannot be called accurate, because the type of roofing material is not taken into account.

Intervals between rafters used for different types of roofing materials

When calculating the pitch of the rafter legs, it is necessary to take into account the characteristics and dimensions of the roofing material. The following types of roofing can be considered the most popular:

• corrugated sheeting;
• ceramic tiles;
• metal tiles;
• ondulin;
• slate.

These types of roofing are used for installation of roofs of residential buildings, bathhouses, and outbuildings. For each type of roof and roof shape, pitched, gable or otherwise, a certain gap between the rafters is used.

Corrugated sheeting

Modern corrugated sheeting durable material, made of galvanized sheet formed into a specific profile. The material is light and durable. When using it, the calculation of the distance between adjacent rafters is 60-90 centimeters. A larger distance is only possible if there is a large cross-section board fastening the rafters. The sheathing for corrugated sheeting is made from a board of thirty, mounted 50 cm apart from each other; if the roof angle is 15°, the corrugated sheet is laid on the sheathing, laid without gaps.

The pitch of the rafters under the corrugated sheet does not depend on its brand. So, C44, the heaviest material is attached to the sheathing with a span of 30 cm, but the pitch of the rafters does not change.

Ceramic tiles

Calculation of the pitch of rafter beams for ceramic tiles, a heavy, expensive material, is somewhat different from others. For material that weighs a lot, only dried strong beams with a section of 50x150, 60x180 cm are used. The optimal distances between rafters, accepted as standards, range from 80 to 120 cm. The choice of interval depends on the slope and type of roof. The calculation must be made taking into account the length of the rafter beam. The longest rafter requires a minimum step and, conversely, the short length of the rafter allows the use of a step of maximum width.

Metal tiles

Metal tiles can easily be called the leader among all roofing materials. It is used for complex, hip, gable, hip, and pitched roofs. Its installation is much simpler than ceramic tiles. Metal tiles can be placed on old roof, replace ceramic tiles, slate, using the old step. Metal tiles are 10 times smaller, so beams of a smaller section 50x150 are used, the pitch between the rafters is from 60-90 cm, standard values. It is especially convenient to insulate such a roof by including the width of roll or sheet insulation in the calculation.

Ondulin

This type of soft roof is becoming increasingly popular, lightweight, easy to install, strong and durable. Ondulin sheets are attached in an overlap to a 40x50 sheathing made of coniferous tree boards (60 cm pitch).

The pitch of the rafter legs is from 60 to 90 cm. Beams are needed with a section of 50x150 or 50x200.

Slate

Slate is widely used to cover outbuildings, bathhouses, houses, and garages. Therefore, many people know what the distance between the rafters should be when using this roofing material. The use of this particular material created a system of rafter pitches of 60-80, battens 50x50. The sheathing is made from 50x50 bars or a thirtieth board, depending on the slope. For a flat pitched roof, a sheathing pitch of 45 cm is used, for a gable roof - 65 cm.

How do the pitches of the rafters of gable and lean-to roofs differ?

Each type of roof has its own strength. The pitch of the rafter beams depends on what safety margin should be included when installing a particular type of roof.

Single-pitched roof structures, which are typical for simple buildings for household purposes, made from beams mounted on walls. The distance between roof rafters directly depends on their length. It is also important to take into account the cross-section of the timber used, based on the fact that the longer the gap, the greater the load.

The gable system, which includes gable, hip, hip and other structures, is always installed with thermal insulation. The standard pitch for such roofs is 1-1.2 meters. In each specific case, the calculation is carried out taking into account, as already mentioned, the weight of the roofing material and other things, SNiP 2.01.85 is taken as the basis, which considers all types of loads and impacts. The step is calculated according to the usual scheme given above. The angle of inclination must be taken into account. The 45° angle allows the use of all types of roofing. For identical roof slopes, the pitch of one side is calculated.

Follow these tips:

• If you decide to install the roof yourself, check the accuracy of your calculations with specialists or, at worst, use the services online calculators construction companies.
• When determining the pitch of the rafters, remember about thermal insulation; any roll or sheet insulation shrinks over time. Remember about ventilation holes, waterproofing.
• If the roof slope is 45° or more, the weight of a person is subtracted from the maximum load, which allows the use of fewer rafters (by 20%).
• Decide what type: layered or required for the selected roof geometry.
• Take your time when choosing a timber; it must be dry (residual moisture no more than 20%), made from coniferous wood.

The distance between the rafters is one of the key parameters affecting the strength of the structure. Proper calculation of the installation pitch of the rafters allows you to build a roof that is resistant to high operating loads.

Roof loads and calculation of the rafter system

The development of a project for a single-pitch or gable roof begins with choosing the type of rafter system, the angle of inclination of the slopes (roof height) and materials for constructing the structure. Calculation of the distance between the rafter legs is carried out taking into account the loads that the roof will experience during operation. Constant loads include:

• the weight of the materials from which the rafter system is made;
• roofing weight;
• weight of materials roofing pie(waterproofing, vapor barrier, insulation);
• weight of finishing elements of a residential attic or attic.

In addition to permanent loads, the roof also experiences temporary loads, which include:

weight of snow cover;

the weight of a person during roof maintenance and repair.

The pitch refers to the distance between the rafters of one slope. When calculating a single slope, gable or complex roof, usually follow the following scheme:

• the length of the future roof slope is measured;
• the resulting value is divided by the optimal numerical value of the rafter pitch;
• one is added to the resulting value, the result is rounded;
• the length of the roof slope is divided by the rounded result.

The final result will allow you to determine at what distance the rafter legs should be placed. Determining the pitch cannot be extremely accurate, since it is necessary to take into account a number of additional factors, including the width of the insulation, the features of installing the sheathing for various types of roofing material. If a roof with a chimney is being designed, the pitch can be adjusted taking into account its location, so that you do not have to subsequently remove part of the rafters and install a supporting structure, such as a special rafter system.

Distance between rafters under slate

Slate is a traditional roofing material. Its advantages include characteristics such as resistance to external influences (excluding mechanical) and low cost. Slate allows you to create a roofing covering, the repair of which can be reduced to replacing individual elements. Slate is heavy and requires the installation of a fairly powerful rafter system. Calculation of the distance at which it is necessary to place the rafters under the slate is carried out taking into account the cross-section of the beam for the manufacture of rafter legs.

The optimal solution is to install a system under slate, in which the gap between the rafters should be at least 800 mm. In order for the slate structure to withstand not only the weight of the material, but also increased external loads, the sheathing is made of timber or boards with a cross-section of at least 30 mm. When calculating a rafter system for slate, you should read that this material has quite large restrictions on the choice of the angle of inclination of the slopes.

Rafters for metal tiles

Metal tiles are actively used as a practical and aesthetic roofing material when arranging a pitched, gable, hip or complex roof. The frame for metal tiles is built according to standard principles. To calculate at what distance it is better to install the rafters, it is necessary to take into account the loads and the angle of the roof. Metal tiles are characterized by their relatively low weight, thanks to which they can serve as a replacement for old slate or ceramic tile roofing. In this case, the rafters will not need to be strengthened or the pitch of their installation changed.

The standard pitch of rafters for metal tiles is 600-900 mm. The cross section of the elements can be 50-150 mm - this is enough to create reliable frame under metal tiles. But if you intend to use insulation, the layer of which in areas with low winter temperatures should be 200 mm, for rafters under metal tiles it is recommended to use 200x50 timber so as not to install additional system holding the insulation. It is better to adjust the gap between the rafters for metal tiles to the width of the sheet or roll insulation.

Corrugated sheeting: rafters and sheathing

Corrugated sheeting is a lightweight and easy-to-use roofing material. Galvanized or coated with a decorative protective layer, corrugated sheets can be used for installation pitched roof a utility room or garage, as well as for a gable roof of a residential building. How to calculate the distance required to install rafters under corrugated sheeting?

To ensure the necessary structural rigidity, it is enough to install the rafters under the corrugated sheets in increments of 600-900 mm. In this case, you need to pay attention to the angle of the roof. Calculations show that under high external loads, it is better to lay corrugated sheets on the system with a minimum step. But if the distance between the rafters under the corrugated sheet is close to the maximum, and the roof slope angle is small, then the structure is strengthened by using more frequent sheathing. In this case, the pitch of the sheathing under the corrugated sheet should be about 50 mm, the width of the elements should be at least 100 mm.

Rafter system for soft roofing

Soft roofs include bitumen and bitumen-polymer roll materials, roofing membranes, as well as soft tiles. Soft roofing is characterized by relatively low weight and the absence of the need to install a massive rafter structure.

The minimum distance between the rafter legs is 600 mm, the maximum is 1500 mm. When installing supports under a soft roof, it is important to take into account the angle of inclination of the slopes: the smaller the angle, the smaller the distance between the supports for a continuous sheathing should be. The choice of step is also influenced by the thickness of the material for the sheathing - the thicker the sheet of plywood or OSB, the larger the installation step of the rafter legs can be.

Ondulin: calculation of rafters

Ondulin (bitumen slate) is laid on a flat, continuous sheathing made of sheet material. This allows the roofing covering to successfully resist wind and snow loads. The sheathing for ondulin rests on the rafters, which should be located in increments of 600 - 1000 mm, depending on the angle of inclination of the gable or pitched roof.

Rafters for ondulin are made of timber with a section of 200×50 mm. When choosing at what distance to place the rafter legs for the structure under the ondulin, it is recommended to take into account the width insulation material to make it easier to install. This calculation allows you to reduce the financial costs of roofing.

Sandwich panel roof

Sandwich roofing is most often erected on houses made of sip panels or hangar-type buildings. A special feature of the sandwich is its bending rigidity, which makes it possible to dispense with the installation of traditional rafters. Small spans from the ridge of a gable roof to the top of the wall (or the distance between the supporting structures of a gable roof) allow the installation of a sandwich without additional supports.

If the span exceeds 4 meters, additional purlins must be installed. To install a sandwich roof on a residential building, a traditional rafter system is often installed, but in this case the rafters can be positioned at larger intervals - they serve as a support for the purlins. The distance between the rafter legs is selected based on the length of the available material for the purlins and the length load-bearing walls. Technical Parameters sandwich allow the roof to withstand high operating loads.

Polycarbonate: construction of a supporting structure

Polycarbonate in lately is actively used as a roofing material. First of all, polycarbonate is in demand in the construction of gazebos, canopies, and winter gardens. The lathing and rafter system for polycarbonate can be made of wood or metal.

Polycarbonate varies in weight depending on the thickness of the sheet. It is recommended to perform lathing under polycarbonate in increments of 600-800 mm. The sheathing (wooden or metal) is mounted on the rafters, which can be straight or arched. Typically, the gap between rafters for polycarbonate is from 1500 to 2300 mm. In order to correctly calculate at what distance it is better to lower the rafters, it is necessary to take into account the glazing area, the size and thickness of the sheets, and take into account that polycarbonate is attached with gaps for thermal expansion.

The distance between the rafters of a gable and pitched roof

Find out what distance between the rafters needs to be made for a gable and shed roof. Maximum distance between the rafters under metal tiles, ondulin and soft roofing.

What is the distance between the rafters of a gable roof?

Erection of the roof is the final stage of any construction. This structural element is load-bearing structure, which takes on all the loads and then evenly distributes them over the surface of the load-bearing walls of the house.

Gable roof

A gable roof is rightfully considered the most common option for arranging suburban housing. And there is a completely logical explanation for this. It's no secret that what simpler design, the easier it is to build and the higher its reliability and performance characteristics.

The gable roof has a triangular shape and consists of two pitched planes connected at the highest point by a ridge girder, and the same number and shape of gables.

In principle, the construction of a gable roof is not considered such a complex operation. But, despite all its simplicity, it requires the most responsible and thoughtful approach.

Structurally, a gable roof has two slopes located in relation to the wall elements of the house at a certain angle, ensuring natural removal of precipitation from its surface. Also, gable roof structures can be of the attic or mansard type.

As a rule, gable roofs are installed on one-story, architecturally simple structures. A huge advantage is that the rafters in this case will not be particularly difficult to install.

The angle of inclination of the roof slopes of gable roofs

The angle of inclination of a gable roof cannot be less than 5 degrees, and in some cases it can even reach 90 degrees. Only at this angle of inclination of the roof slopes will the rafters be able to adequately cope with the function assigned to them.

To choose the angle of inclination of the slopes for gable roof influenced by a huge number of factors, such as climatic conditions, the type of roofing material chosen and architectural style buildings.

For example, flat roofs are ideal for construction in areas where strong hurricane winds constantly blow, but structures with steep slopes are an excellent option for those areas where significant amounts of precipitation fall.

Also, the angle of the roof affects its cost, this is due to the fact that a roof with a small angle of roof slopes will use much more roofing material than one with a large one.

However, this is not the only important parameter when building a gable roof. Equally important when forming a gable roof is the correct installation and fastening of the rafter system, as well as the step size between its elements.

Also, the quality of the structure is affected by the fastening of the rafters to the Mauerlat and ridge run. Particularly reliable fastening can be formed using cutting and additional fixation of connections with bolts.

The distance between the rafter legs (otherwise known as the pitch of the rafters) is considered one of the most important parameters when installing a roof, which affects its strength characteristics.

A correctly calculated pitch between the rafters of a gable roof allows you to create a roof that is resistant to the high loads to which it will be subjected during operation.

Let's take a closer look at what the distance between the rafter legs should be.

Rafter spacing for a gable roof

Distance between rafter legs gable roof calculated during design. Correcting any mistakes made at this stage is quite problematic, and therefore if you are not sure own strength, then it is better to entrust its implementation to professional architects.

Reliable rafters are the basis of any house roof.

The rafter pitch is calculated taking into account the loads to which the structure will be subjected during operation and the angle of inclination of the roof slopes.

When making a proper calculation, the presence or absence of an insulating layer and the cross-section must be taken into account. structural elements rafter system, type of sheathing and roofing. It is necessary to correctly calculate the loads, as this will help you avoid making mistakes when choosing the rafter section.

The rafter pitch is the distance between two adjacent trusses.

Step-by-step instructions for calculating rafter pitch for a gable roof:

• We calculate the estimated length of the roof slopes.
• Divide the resulting number by optimal sizes step.
• Add one to the resulting number and round the result.
• We divide the length of the slopes by the rounded result.

As a result of these simple calculations, you will get the distance at which the rafters should be installed.

The pitch between the rafters cannot be calculated accurately, since to obtain more accurate data it is necessary to take into account a huge number of parameters, ranging from the width of the insulating layer, the type of roofing material and even the distance between the gable roof sheathing elements. Rafters installed correctly will serve you faithfully for decades.

Rafter spacing under asbestos-cement slate

An important parameter asbestos-cement slate is its significant weight, due to which it requires the installation of powerful rafters capable of withstanding heavy loads. The distance between the rafters is selected based on the cross-section of the timber used to make the rafters.

It is equally important that the rafters of a gable roof are fastened correctly, as this will provide it with a high degree of reliability and a long service life.

The optimal pitch between the rafters when using asbestos-cement slate should not be less than 800 mm. Thanks to this, the rafters can easily cope with the task assigned to them.

Rafters for metal tiles

We will not talk about all the advantages and disadvantages of this material; a lot has already been said about this. Let's take a better look at what the pitch should be between the load-bearing elements of the structure. Rafters for metal tiles are installed in accordance with existing standards and requirements.

Due to its low weight, this coating can be used to cover roofs that previously had ceramic tiles or asbestos-cement slate laid on them.

The size between the rafters in this case ranges from 600 to 900 mm, and the cross-section of the lumber is 50 by 150 mm. This step between the rafters will create the most reliable load-bearing frame for the roof.

However, in areas characterized by snowy winters, it is preferable to arrange a distance between rafters of 200 mm, and to use timber with a section of 50 by 200 mm for the manufacture of structural elements.

In order not to mount special system to maintain the insulation, you can adjust the distance between the rafters to the width of the thermal insulation material.

Rafters for ondulin

Ondulin or flexible tiles must be laid on a continuous, perfectly flat sheathing, and it is better if it is made of some kind of sheet material, which will allow the roof to withstand all loads.

The sheathing is attached to the rafter legs, located in increments of 600 to 1000 mm, depending on the angle of inclination of the roof slopes of the gable roof.

The correctly selected distance between the elements of the rafter system guarantees everything supporting frame high degree of strength and durability of the entire structure.

What is the distance between the rafters of a gable roof, YouSpec Construction Encyclopedia

The correctly selected distance between the elements of the rafter system guarantees the entire supporting frame a high degree of strength and durability of the entire

Distance between rafters: correct calculation

The reliability of the roof and its service life mainly depend on how correctly the calculations are made.

One of the most important parameters rafter system is how far apart the rafters are located.

After all, the distribution of the load on the frame depends precisely on this desired parameter.

If the calculation is made incorrectly, deformation may occur and the roof will collapse.

Therefore, it is extremely important to accurately calculate the interval between the rafters when drawing up a roof project.

Basic principles of calculation

The pitch of the rafters is the distance from one rafter leg to the other.

When constructing roofs of private houses, this value is 1 meter.

But this figure is approximate.

To obtain the exact size of the interval, it is necessary to calculate the load-bearing capacity of the rafter system of the selected type.

To perform the correct calculation, use the following scheme:

• first you need to determine the length of the roof slope;
• Now the resulting figure should be divided by the value of the approximately selected rafter pitch. If you previously selected its value as 1 meter, then you need to divide by 1.

If you chose 0.8, then you should divide by 0.8, etc.;

• after that, one is added to the result obtained and the resulting value is rounded up. This action is necessary in order to obtain the exact number of rafters that will need to be installed on one slope;
• the total length of the slope must be divided by the number of rafter legs obtained in the previous calculation. And we get the exact distance between them.

To understand this better, let's look at an example.

Having measured the length of the roof slope, we got 27.5 meters.

We choose a step of 1 meter to make it more convenient to count.

Now we add the unit 27.5 m +1 = 28.5 m.

Round up to the nearest value and get the number 29.

That is, 29 rafter legs must be installed on one slope of our roof.

Now we divide the length of the roof by their number: 27.5/29 = 0.95 m.

This means that in our case, the pitch of the rafter legs should be 0.95 meters.

This is a general calculation.

In which the peculiarities of a particular roofing material are not taken into account.

And he can significantly change this parameter.

When you know what kind of material you will use on the roof, you will have to make some changes to the calculation procedure.

Optimal and minimum value

The step is a unit of calculation.

After all, it depends, first of all, on the load on the roof frame and the cross-section of the rafter legs.

You can take a thick board for their construction and make the interval between them 120 cm.

At this distance, the sheathing may begin to sag.

And how to install the insulation?

After all, most materials have a width of 1 meter.

So when calculating, they take an approximate step of 1 meter.

The minimum distance between rafter legs is 70 cm.

And to receive optimal value For each material it is necessary to perform calculations.

Determining the pitch for a pitched roof

The pitched roof is the simplest.

After all, in roof truss Such a roof has only rafter legs.

There are no struts, racks, or braces in its design.

Such a roof is usually installed on garages, outbuildings, and bathhouses.

As can be seen from the table, rafter step depends on their length and cross-section.

Distance between rafters for a gable roof

A gable roof is much more common than a shed roof.

And it’s easy to explain such popularity: the design is very simple, but despite all its simplicity, the gable roof is distinguished by its reliability.

Its design can be easily adjusted to any climatic conditions and any roofing material.

When calculating the pitch of the rafters of a gable roof, everything is done according to common system calculation (see above).

If the slopes have the same length, then it is enough to perform calculations for one slope.

If the stingrays different lengths, then the calculation is performed for each slope.

It should be remembered that the maximum pitch values ​​for the rafter legs are 70 and 120 cm.

What is the pitch depending on the roofing material

If ondulin is used as a roofing material, then the rafter system is constructed from pine boards with a cross section of 50 x 200 mm, and the rafters should be located at a distance of at least 60 cm and no more than 90 cm from each other.

A sheathing of timber with a cross-section of 40 x 50 mm is laid on top.

Metal tiles

Metal roofing during construction country houses is used most often.

Because this material is much lighter than ceramic or cement tiles.

Although appearance very similar to her.

The low weight of metal tiles makes it possible to use boards of a smaller cross-section when creating a rafter system, and to use thinner bars for sheathing.

More about the counter-lattice for metal tiles.

About the hip roof with hanging rafters via the link. Also about the design of hanging rafters.

About the price of Viking metal tiles here. Specifications, photos, reviews.

Reducing the size of the elements of the rafter leg system, in turn, reduces the load on the walls of the building and its foundation.

When constructing a rafter system under metal tiles, the rafters are mounted in increments of 60–95 cm.

The cross-section of the material is 50 x 150 mm.

According to experts, if you place insulation with a thickness of 150 mm in the space between the rafters, then attic will be created the most comfortable conditions for accommodation.

To ensure ventilation of the space where the insulation is laid, when installing the rafter system, holes near the upper roof with a diameter of 12 mm are drilled.

The technology for manufacturing a rafter system for metal tiles does not differ significantly from the technology for manufacturing a frame for other roofing materials.

Its only difference is the installation at the top.

Mounting of the upper support is not carried out ridge beam on the side, and on the ridge run.

Availability free zone between the rafters allows air to fully circulate under the flooring, which helps prevent condensation from forming.

Ceramic tiles

The design of the system for ceramic tiles has its own characteristics.

After all, clay is used to make such roofing material.

And this is very heavy material.

If you compare metal tiles and ceramic tiles, the latter weighs 10 times more.

Accordingly, the rafter system is significantly different.

On 1 square meter the roof surface bears a load of 40 - 60 kg, depending on the manufacturer and brand of the product.

Rafters for this frame system made from wood that has been dried for a long time.

Such wood should have a moisture content of no more than 15%.

A beam with a cross-section of 50 x 150 or 60 x 180 mm is used.

And the distance between the rafter legs can be 80 - 130 cm.

The exact value can be given if the angle of inclination of the slopes is known.

If the angle of inclination is 15 degrees, then the pitch of the rafters will be 80 cm.

And if the angle of inclination, for example, is 75 degrees, then the step may be larger - 130 cm.

The interval between rafters is not greater than 130 cm.

Also, when calculating the pitch of the rafters, their length is taken into account.

The larger the dyne, the smaller the distance between them.

The shorter the rafter legs, the greater the distance can be made.

If the angle of inclination is 45 degrees, then the roofer can safely move on the roof if the rafter pitch is 80 cm.

Corrugated sheeting

When creating a rafter system under corrugated sheeting, the minimum distance between the rafter legs is 60 cm.

The maximum size is 90 cm.

If for some reason the pitch of the rafters is more than 90 cm, then it becomes necessary to install cross-section boards of large cross-section.

The rafter legs themselves can have a cross-section of 50 x 100 or 50 x 150 mm.

Despite the appearance large quantity new roofing materials, asbestos-cement slate remains one of the most popular.

If you plan to lay slate on the roof, then the rafters should have a cross-section of 50 x 100 or 50 x 150 mm.

The distance between them is made no less than 60 and no more than 80 cm.

The lathing is made of timber with a cross-section of 50 x 50 mm or boards with a cross-section of 25 x 100 mm.

When constructing any building structure, it should be remembered that there are still unforeseen situations.

And, therefore, when calculating the sections of rafters and the distance between them, it is necessary to provide a safety margin.

Distance between rafters: single-pitched, gable roof

One of the most important parameters when calculating a rafter system is the distance between the rafters. After all, it depends on it how strong and stable it will be.