Post pitch in a frame house for insulation. External walls of a frame house
Wide use frame technology due to the obvious advantages of this method of construction. The most serious advantages include simple design walls, an important element of which are the vertical frame elements - racks. The strength of the building and the cost of construction depend on the correct choice of material for manufacturing and the pitch of the racks.
Components of the frame of enclosing structures
The walls of a frame building are an important part of the building. Wherein Basic structure consists of the following elements:
- Bottom harness;
- Upper harness;
- Racks.
The first two elements are horizontal and are connected to each other using vertically installed racks. It is the latter that take on the main load from the building structures located above. Therefore, determining the size of the racks and the distance between them must be approached responsibly and as seriously as possible.
Factors influencing strut pitch
Competent design of the main parameters of the racks of a frame building, namely the section and pitch, involves taking into account the following factors:
- The number of floors of the building, which affects both of these parameters. This is explained by the fact that it is the racks that act as the main load-bearing element of the wall frame;
- Type of lumber and wood used in manufacturing. The requirements for them are set out in two regulatory documents: SNiPe II-25-80 as updated in 2011 and GOST 2454;
- Type of wall provided for by the project. Posts are often used as a base for cladding the building envelope, both inside and outside the building. This must be taken into account when determining the step between them.
Wall frame posts are quite rightly considered the basic part power frame the buildings. This explains why such serious attention is paid to the choice of material for their manufacture and the determination of the pitch between adjacent elements.
Optimal distance between posts
Most of the reference literature devoted to frame private housing construction determines the optimal size between adjacent racks, equal to:
- 60 cm, if measured along the axis of the bar used for manufacturing;
- 57.5 cm, if you calculate the distance between the edges of adjacent bars.
As a rule, no serious explanations or justification for such figures are provided. However, serious experience in practical frame construction, accumulated in last years, confirms the correctness of the indicated values. Moreover, a significant part of standard frame house projects developed by serious and reputable design or contracting organizations provide for a rack pitch of 60 cm.
As the only addition to the above, it should be noted that many experienced professional builders admit the possibility of a slight deviation from the given figures, at which the pitch of the vertical wall elements frame house varies between 50 and 70 cm. The maximum value of this parameter is 100 cm, but in practice such buildings are extremely difficult to meet. Required condition all of these figures indicate that they are used exclusively in the manufacture of racks quality wood, having no defects and belonging to the 1st grade.
The increase in housing costs and the deterioration of the environmental situation in cities have led to the fact that more and more people are planning to live in the suburbs in a private house that is devoid of the described disadvantages.
The private housing construction market does not stand still and offers several technologies for constructing a private house. One of these is, which has been rapidly developing in recent years. With this technology a private house it is built from panels that are manufactured in a factory or assembled at the construction site. Dimensions and shape wall panels correspond to the house design you have chosen, so its assembly does not take large quantity time.
The durability of a constructed frame house depends not only on the treatment of wooden structures with antiseptics or fire retardants, but also on the correct assembly of the frame and carefully selected insulation.
The frame is the skeleton of the future building, since its elements provide spatial rigidity to the entire structure. The design of the frame is largely influenced by the selected insulation of the future home, since its dimensions must be taken into account when choosing the pitch of the frame posts. The frame itself serves enough for a long time, since it is hidden under a layer of insulation and external finishing, which means it is practically unaffected by external conditions.
Another advantage of frame house construction is that you can always change the internal or external cladding or strengthen elements of the house without affecting the people living in it. If the house is brick, then to carry out similar work it is almost always necessary to break down the walls.
Distance between frame posts
The main question facing the builder of a frame house is what pitch between the posts should be chosen. In addition, it is important to decide what should be used as a guide when choosing the pitch of the racks and how to take into account the deformation gaps between the facing materials.
These questions are of interest to everyone who is building their own frame house. However, they do not have an exact answer, since they depend on many factors. Specialized literature says that the optimal spacing of the racks is a distance of 600 mm at the centers of the bars or 575 mm between adjacent bars. At the same time, it is practically not explained how these figures are justified.
What can guide you when choosing a step? Possible options recommendations could be:
- the height of the future building, which affects not only the pitch of the racks, but also their cross-section. The load-bearing loads on each rack individually depend on the size of the racks and the height of the building;
- lumber from which the house racks will be made must comply with SNiP II-25-80 “Wooden structures”, and their dimensions must comply with GOST 24454 “Lumber coniferous species. Dimensions";
- in the absence of a verification calculation, the distance between adjacent racks depends on the maximum dimensions of the racks, the load they perceive, and the type of wall;
- the racks of the house should be located in butt openings, but be continuous in height;
- the pitch of the racks depends on the rules for constructing a frame house, which have been developed over years of practice in private house building. In addition, racks are the basic elements of the power frame of a house, on which the duration of high-quality operation of the building depends. major repairs, therefore, maintaining the pitch of the racks - important element construction technologies.
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Optimal strut pitch
The most optimal strut spacing in frame house is considered to be 50-70 cm. This distance can vary within certain limits depending on the construction conditions and the design of the house, but should not exceed 1 m. Optimal sizes provide stability and strength to the frame and allow the use of standard materials for cladding.
In those places where door or window openings will be installed, the pitch of the racks must correspond to the dimensions of the boxes. If it is not possible to do this condition, then it is necessary to install additional racks that will support the frames of windows or doors.
For the manufacture of stands, 1st grade wood without defects is used. Their cross-section must be sufficient to withstand loads from finished house. Considering that the thickness of the walls of a frame house depends on the region of construction and external temperatures in the cold season, but is not less than 100 mm, then the minimum width of the bars for racks should not be less than 100 mm with a minimum thickness of 50 mm. In climatic zones I and II, the cross-section of the bars should not be less than 50x150 mm.
If according to the project the house is two-story or large (dimensions along the foundation are at least 12x8 m), then the racks must be made of bars with a cross-section of at least 150x150 mm. For more compact buildings, 100x150 mm bars can also be used. Moreover, the width of the racks depends not only on their strength and load resistance, but also on the materials used for insulation and cladding of the building. The racks are installed vertically with careful compliance with the design distribution and are connected to the lower and upper trim with 5x5x5 mm tenons, with additional fastening with brackets or corners. It is necessary to carefully control the location of the edges of the racks in the same plane within the walls, as this affects the quality of the cladding and appearance building.
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Selection of strut pitch depending on the materials used
As mentioned earlier, the selected strut pitch depends not only on the loads, but also on the materials used. When calculating it, it is necessary to take into account dimensions facing materials (oriented strand board (OSB) or plywood), insulation and materials used for interior decoration Houses. The result of such an integrated approach will be minimal waste of materials used and significant savings in both time and effort during the construction of a frame house.
Below we give examples of how to select the pitch of the racks when various options wall kits.
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Insulation of a frame house with mineral wool
If as a wall kit, i.e. of all materials that make up the entire wall from the outside to the inside of the house, siding, waterproofing, OSB, mineral insulation, kraft paper, plasterboard, then the pitch of the racks should be selected according to the size of the plasterboard or OSB, since for other materials the distance between the racks is not of fundamental importance. Moreover, emphasis should be placed on the dimensions of the drywall, since OSB sheets are easier to trim taking into account the gap for deformation.
If, in a wall set, basalt slabs “Rockwool” are used as insulation (with a width of 600 mm and a deformation band of 50 mm), then the best option The walls will be: OSB, waterproofing, basalt slab, lining. Considering that the lining does not affect the distance between drains, and the deformation band of basalt slabs allows you to change this step from 560 to 595 mm, the determining factor is the size of the OSB slabs.
If the house design does not involve balconies, complex corners or bay windows, then an option is possible when OSB sheets are attached from the outside without trimming, then with their dimensions (2500x1250 mm) the pitch of the posts will be equal to 625 mm (the distance between the posts is 575 mm), and expansion joints are being fulfilled circular saw already after fixing the sheets on the racks. This step between the posts is enough to install basalt slabs using the deformation strip without additional trimming.
When you are designing a frame house without practical experience in constructing such buildings, many questions inevitably arise. One of them is at what distance from each other should the racks be placed in the walls.
One thing can be said right away: it all depends on the materials that you plan to use in construction. For example, if you plan to sheathe the frame outside and inside with boards, then there is no reason to rely on sheathing material in your calculations. In this case, it is better to proceed from the size of the insulation. Let's say you are going to use Rockwool insulating basalt slabs. Standard width such slabs are 60 cm. This means that it is most convenient to make internal gaps between the posts 58 cm, then the insulation will fill the sections tightly, and there will be less need to cut it.But the cladding can also be made of other materials, which can have strict dimensions in width and length. When such materials are relatively expensive, there is a desire to coordinate their dimensions with the distance between the posts so that there are fewer scraps. After all, insulation boards are easier to fit, they are easy to cut, you can even fill the gaps with pieces, and there will be almost no scraps.
It is unlikely that you would want to have a house without windows and doors. Narrow windows that fit into a vertical clearance of about 60 cm are not a problem to order, although they are not always convenient. But you are unlikely to like using doors of such width. To do this, the whole family will have to go on a diet for a long time. That is, you need to take into account the fact that the distance between the racks will not be uniform along the entire perimeter of the load-bearing walls. Door and window frames can have different proportions, and each of them will need to be built into the wall, breaking the orderly rows of racks in the most bizarre way.
Thus, it remains to be recognized that there simply cannot be any strictly established distances between the racks. It all depends on your capabilities, taste and desire. Rather, one must proceed from the point of ensuring the necessary strength for the entire structure as a whole. Some home owners feel offended after strong wind discover the roof of your home in your neighbors' garden. For some reason, others become very upset if the structure falls into disarray, like a house of cards. Like in the tale of the three little pigs.
So it is better to pay attention to the fact that the racks themselves have a sufficient cross-section, and that the distance between them is not excessive. Most often, racks are made from edged boards with a section of 50X150mm. The distance between them, depending on the specific location of the wall, can vary from 50 cm to 80 cm. In some places, the distance between the racks will simply have to be spaced out to 100-105 cm. This applies, first of all, to door and window openings. So in some places it is not harmful to use timber with a cross-section of 100X150mm, or even 150X150mm, as racks.
Vertical racks, even relatively small in diameter, if they are straight, can withstand significant vertical loads. But a stand arched becomes noticeably lower in its load-bearing capacity. When you select the material for these structural parts, pay attention to their quality: the racks should be straight, not have large knots, especially falling out ones, rot and rot. When there is no choice, you have to use what you have. And if the material does not inspire much confidence, then it is better to play it safe and place the racks even more often than it would seem to be required by calculations.
But loads directed from top to bottom that house structures experience are not all. As already mentioned, the wind also plays a role in testing the strength of a house. Therefore, from reliable connection of the ends of the racks with the upper and bottom harness, between which these racks are located, also depends on the strength of the entire structure. Accordingly, than more racks, those more nodes connections, and the stronger the building will be. So take your pick golden mean between the unbridled fanaticism of extravagance and unreasonable frugality - and everything will be all right.
The strength of a frame house is determined by its design. The weight of the walls, ceilings and roof is supported by load-bearing frame frame house. For the strength of a frame house, it is important to choose the correct thickness of the supporting posts, as well as the distance between the posts. There are rules. Today we will discuss how to calculate the distance between posts in a frame house, the so-called pitch of posts in a frame house.
Pitch of racks in a frame house
The distance of racks in a frame house is determined by their strength and future load. The stronger the frame posts, the larger the gaps between them can be. In addition, the size of the racks of a frame house is influenced by the size of the finishing materials. Why should the distance between supports take into account the dimensions of the finishing panels?
Step in frame wall.
Let's give an example. For ease of installation of sheets OSB step They try to choose between racks taking into account their sizes. The OSB dimensions are 2500x1250 mm. This means that if the distance between the posts is a multiple of 1250 mm (or a multiple of 2500 mm), the consumption finishing material the trimmings will be quite minimal. The edges OSB sheet will be attached to the stand. If the distance is greater than 1250, part of the OSB sheet will be cut off during installation.
They also try to take into account the dimensions of the future insulation. For example, if the insulation of a frame house from the inside is carried out with mats made of mineral wool Rockwool, then their dimensions are 1200x600 mm with a deformation strip of 50 mm. Then the distance between the racks for the insulation should be 550 mm. Which does not correspond to 1250 mm OSB. In this case, when choosing the support spacing, the dimensions of the insulation are not taken into account, and additional strips are provided for its installation in the frame.
On a note
It is also necessary to take into account that in places where doors and windows are installed, the distance between the posts in a frame house may be greater or less. The distance should correspond to the width of the future window or doorway.
Choice fastening elements will be determined by the frame material. The vertical posts of a wooden frame house are attached to the lower and upper frames using metal corners and nails. And the metal vertical supports are bolted or arc welded.
So, we’ve sorted out the peculiarities of choosing a pitch and selecting fasteners. Now let's turn to the calculations and calculate the weight of the future frame, the thickness of the supports and the distance between them.
How much does a frame weigh?
The frame of the house is carrier system. Its strength must withstand the pressure of walls, ceilings and roofs. Therefore, to calculate the racks of a frame house, it is necessary to determine the weight of the future structure. How to do it?
Weight of frame walls. There are several methods for determining the weight of a future structure. Let's give two:
- Determining the weight of a building using an online calculator. In this option, the values of the width and length of the walls of the building, its height, the number of load-bearing partitions, as well as the material of the walls, their thickness are entered into the calculator and the finished result is obtained - the approximate weight of the future structure.
- Calculations using construction tables. This is more complex and painstaking work, during which you can get a more accurate result. According to construction tables approximate is determined specific gravity 1 cu. m, as well as the linear weight of each meter of floors and roofing sheets. The data obtained is multiplied by the area of the walls of the house or roof, summed up and added to total weight frame house.
The weight of the future structure obtained in the calculations is multiplied by a factor of 1.1. It takes into account the additional weight of plumbing fixtures and furniture that will be located in the building. As a result, we get the weight that the house frame must withstand for many years of use.
According to the online calculator, we get that 8x8 m with a roof made of metal profile And wooden joists, V climatic zone With winter temperatures-10 will be about 10.5 tons. Multiplying by the coefficient, we get 11.55 tons, which for convenience of calculations we round up to 12 tons of construction weight. So what to do next?
Frame house racks
Next, let's look at strength. wooden racks, and find out how much weight each support post can support. Traditionally for wooden frames one-story buildings are used corner posts frame house with a cross-section of at least 100x50 mm, for two-story houses - 150x50 mm. Using reference tables, we determine the load-bearing capacity frame rack.
Distance between bases. On a note
Calculation of bearing capacity using formulas is quite complex and involves knowledge of the resistance of materials.
According to the directory physical properties wood, the compressive strength of wood is 30 – 50 MPa (depending on the type of wood). This means that each cm of cross-section can support 30-50 kg of weight. The wall posts of a 100x50 mm frame house are guaranteed to withstand 300 kg.
Taking into account the total weight of the house determined earlier, we can calculate minimum number support posts. To do this, we divide 12,000 kg by 300 kg, as a result of which we obtain that the installation of racks will require 40 boards with a cross-section of 100x50 mm.
Distance between supports
The distance of racks in a frame house is determined by the load or weight of the house, the number of supports. Using the data obtained, we determine the required distance between the frame posts. To do this, we calculate the total perimeter of the wall. In a house 8x8 m it will be 32 m. Then we divide the resulting 32 m by the number of racks - 40 pieces. We get a distance of 0.8 m or 800 mm.
In the construction literature there is general recommendations, how to properly fasten the racks of a frame house. They say that if it is impossible to carry out construction calculations, the step between is selected in the amount of 500 to 700 mm. And one more thing: it is accepted that the pitch of the racks of a frame house should not exceed 1 m.