You need to know the main rule - the installation of jibs. The jib is an important, one of the main elements to ensure the rigidity and stability of the structure of your wooden house. Without this detail, the house will be shaky, easily exposed to the forces of nature, and its service life will be reduced tenfold.
Jaws: necessity or myth
There is an opinion among the people, "myths" about the need for jibs:
1. jibs are an extra waste of time and money during construction. So, people far from the construction business can argue. As mentioned earlier, the fundamental role of this structural element lies in its rigidity.
2. They can be replaced with outer skin. You can do without them if you are going to build a barn or other outbuilding. However, the exterior trim must be tiled or trim boards must be at a 45-degree angle.
3. For internal walls (partitions), they can be neglected. In this case, the load taken by the house structure from wind, snow on the roof and static load from the roof itself will be taken only by the outer walls. Partitions without braces will undergo deformation, and the entire interior finish will be broken and cracks will appear.
4. Struts are jibs. Often developers confuse spacers with jibs. In construction, spacers are used when the height of the walls is 3 m or more. This is done to eliminate the "spring" effect on the board. But they do not give the structure of the house the necessary rigidity and stability in three-dimensional space.
Jambs in a frame house are a must!
If you still doubt the installation of jibs when building a house and hope that they can be replaced with sheet sheathing or slabs (chipboard, OSB), then on the Internet you can find a lot of photos of houses without jibs that refute your hopes.
Consider what the use of jibs gives when building a house:
Without the use of these parts, the frame and the whole house will not have sufficient reliability and durability.
Prevents deformation and damage to the exterior and interior of the house.
Eliminates the "walking" of the interwall insulation.
Stabilizes the house and prevents it from folding.
Wind load, "snow" load and static load from the roof itself are distributed evenly over the entire frame structure of the building.
Correct jibs
In the construction, it is important not only to provide for the presence of jibs, but also to make and fix them correctly:
1. The jib installation angle is 45 ° (ideal angle, provides maximum structural rigidity). In places where there are door and window openings, it is not always possible to maintain this angle. Therefore, an angle of 60 ° is allowed, and an increase in the angle is compensated by an increase in the number of jibs.
2. Do not use hollow jibs. An exception may be small one-story buildings with flexible diagonal connections.
3. Correctly install the jibs from the bottom from the center of the wall up to the ceiling of the vertical rack with the top trim. At the top, the jibs should fit snugly (without gaps) against the edges of the uprights and the top floor.
4. When installing jibs under them in vertical racks, in the upper and lower trim, it is necessary to make grooves for the jibs. The depth of the groove is performed depending on the thickness of the jibs. In a steel frame, the jibs must go inside the metal profile of the racks.
5. Cross-sectional dimensions of jibs are calculated depending on the requirements of SNiP for each region separately.
6. Fasten the corner stiffeners to each upright with two nails.
Mistakes that can be made when installing jibs:
Use of wood with unnatural moisture. With further drying, the boards “dry out” and gaps form in tight joints. The rigidity of the structure is significantly reduced.
The cross-sectional dimensions of the frame elements are smaller than necessary to resist the loads.
The use of low-quality lumber.
Placement of jibs in the corners. It leads to a decrease in the rigidity and stability of the structure.
The consequences of building a frame house without jibs
Refusal to use jibs in the construction of a frame house can lead to disastrous consequences:
destruction of the house under the influence of snow and wind loads;
outer sheathing with plywood (it has a high degree of spatial rigidity compared to chipboard, OSB, etc.) does not provide the necessary rigidity;
under the influence of soil movement, the house can "walk" by itself;
Temporary jibs
The installation of temporary braces is a necessary step at the stage of erection of the building frame. They are used:
During the installation of corner posts. Temporary braces prevent the connection of the corner post with the lower trim from loosening until the upper trim is installed.
For leveling stud walls and resolving the following issues when installing doors, windows, interior and exterior trim. When the doors are not hung, and the finishing plates do not converge in the corner.
For installing and leveling roof rafters.
The procedure for installing temporary jibs:
1. First, align the corners. For this operation, you can use a bubble or laser level. You can also use the "American" method. Fix the level on a board as long as the height of the wall.
2. Temporary braces are fastened with blocks fixed below to the floor or platform, above to the upper lags.
3. The installation step of the jibs is from 1.2 m to 1.5 m. They are made from a board with a section of 25x150 mm.
With the help of temporary jibs, significant defects can be corrected by creating the necessary leverage.
Do-it-yourself jibs
The jibs, although a crucial element of the frame house, but making them yourself will not be particularly difficult:
1. As a rule, a board with a section of 25x100 mm is used (for areas with increased wind load, a section of 50x100 mm is recommended). The length of the board should be 30% longer than the height of the wall.
2. We apply to vertical posts at an angle of 45 - 60 ° (depending on the design of the wall, where it works). We mark the grooves in the racks, from the upper to the lower lags. The jib should come from the center of the wall, the top is directed towards the upper corner of the rack, the bottom, if possible, is retracted to the maximum distance.
3. With an ordinary hacksaw or hand-held circular saw, we make grooves and remove the tree with a chisel. The corners of the jib itself are also cut along the outsole.
4. The jib should fit snugly into the grooves made to ensure maximum rigidity.
5. In the places of window and door openings, it is recommended to place the jibs from the corner to the hole. Thus, additional fastening of racks of apertures is carried out.
6. The jibs are fastened with nails, 2 pcs. for each vertical rack and 3 pcs. on the top and bottom trim.
By following these jib building steps, you'll get the stiffness you need to handle wind and snow loads.
The reliability of a frame house, the degree of its resistance to wind, snow, other adverse weather conditions, the service life of such a structure are determined by the rigidity of its structure. The most popular method of strengthening the frame is the installation of jibs. Let's figure out whether it is worth spending your time and energy on installing the jibs, or is it quite possible to do without them.
What are jibs, and what are they
Jambs are additional components of the house frame, which provide an increase in the degree of reliability of the structure of the structure and an increase in the life of the building. These elements are usually mounted at an angle of 45°, this figure changes to 60° if the jib is installed near door or window openings, as well as with wall junctions.
Most often, the jib is a wooden beam made from a board with a section of 25 by 100 mm. In most cases, this size is optimal and the use of larger frame reinforcement elements is usually not advisable. Stabilizers with the mentioned section strengthen the structure of the house, but at the same time do not make it heavier and do not create an additional load on the foundation.
The jibs are also made of metal. They are heavier and unpopular in Russia. In the USA, on the contrary, metal jibs are mostly found. The advantage of such jibs is a low price and high installation speed.
The disadvantage of these jibs in comparison with wooden ones is that the latter resist both compression and stretching, while metal ones resist only stretching. Therefore, when installing metal jibs, you have to put them crosswise for adequate resistance to the changing load vector. In addition, additional waterproofing work must be carried out before the installation of metal components.
Stubs can be installed both permanently and temporarily. The need to install temporary jibs arises if the tiled wall cladding (OSB boards) has not yet been equipped, however, the frame structure needs to be strengthened for the duration of this work.
Why you can not do without jibs
The frame house itself is a fairly solid structure, however, its design also needs to be strengthened. The fact is that the components of the frame before installing the jibs are only parallel and perpendicular to each other. This arrangement of the frame elements makes it unstable to ground displacements, wind and other "transverse" loads.
If there are no elements in the frame of the building that provide rigidity, then such a house is at risk of losing the geometry of the structure, deformation of both external and internal finishes. It is possible that under the influence of serious lateral loads, the house can “fold”.
The lack of rigidity of the frame leads to a decrease in the durability of the structure of the house as a whole. Not so radical, but rather unpleasant consequences of the lack of reinforcement of the frame are heat losses due to the fact that the thermal insulation layer loses its integrity when the walls are displaced.
The result of incorrect distribution of jibs and their insufficient number
So, the result of the correct installation of the jibs is:
· prevention of vibrations and destruction of walls under the influence of weather factors;
· no deformation of walls and internal partitions under loads;
· increasing the rigidity of load-bearing structures;
· more reliable fastening of heat-insulating materials inside the walls;
· ensuring uniform distribution of the load between the elements of the frame.
After the installation of the jibs, the frame house building will successfully withstand heavy winds, landslides and even earthquakes. Snow that has accumulated on the roof in winter will also not pose a threat to the integrity of the house.
Is there a possibility of waiver
Recently, plywood sheathing or OSB (oriented strand board) has increasingly become the jib. The use of plywood is more justified, since it has a greater coefficient of spatial rigidity in comparison with chipboard and OSB.
Nevertheless, even those frame houses that are sheathed with high-quality plywood, but lack braces, often do not withstand the impacts of the elements, although they are adapted for normal loads under normal conditions.
Jambs can be omitted only during the construction of small frame structures that are not residential buildings, but have, for example, an economic purpose. So, frame garages, sheds or toilets may well do with sheathing without installing jibs, since, due to the small area of \u200b\u200bthe supporting elements, they are less susceptible to wind and other weather loads.
Consequences of a hurricane
You should be aware that the skin in this case must be made of strong material, supplied in the form of relatively large components. Finishing elements must be positioned similarly to jibs - at an angle of 45 °
Common Problems
In order for the jibs to really perform their function with high quality and justify the financial and labor investments in their installation, one should strictly adhere to the basic rules for the installation of these structures.
Here are some setup tips:
· the jibs must be cut into the upper, lower horizontal strapping of the frame and into the vertical racks - only in this way the frame will become as rigid as possible;
· installation of jibs from the inside is less convenient, but ensures the guaranteed absence of "cold bridges";
· when attaching the jibs to the frame elements, you need to use only nails, but not self-tapping screws;
· on one wall it is quite enough to install only two multidirectional jibs. A larger number of reinforcing elements is unlikely to significantly increase the degree of rigidity of the frame;
· installation must be carried out from the central part of the lower beam to the corners at the top. This installation order will ensure the formation of a right triangle between the stiffeners and the corner post;
· if the jibs are installed exclusively on the external walls of the structure, then most of the static load falls on them, and not on the internal partitions.
Remember: the installation of jibs does not at all guarantee protection of the house from external loads if the material of these elements is chosen incorrectly or the installation process is carried out with errors.
Consequences of errors in material selection and installation:
· the use of hollow jibs - the degree of their wear resistance is low;
· a similar problem occurs when choosing jibs with a small cross section and generally low-quality lumber;
· the choice of metal strips or ribbons for large houses as jibs - such reinforcing elements are more suitable for small buildings;
· the use of poorly dried wood - after drying, gaps form in the areas of component connections and the rigidity of the structure decreases;
· installation of jibs in the corners is fraught with a decrease in the stability index of the structure as a whole.
It is obvious that the use of jibs is a prerequisite for strengthening a frame residential building. Structures in which such a solution was implemented will serve for a sufficiently long period, during which they will successfully withstand the elements and other loads. Thus, the jibs will actually insure the owner against much greater losses than those associated with the manufacture and installation of these elements.
http://www.rmnt.ru/ - site RMNT.ru
They are in demand due to their affordable cost, good technical characteristics, low thermal conductivity and durability. In order for the cottage to calmly endure various climatic loads without deformation and damage to the load-bearing walls, roofs and other parts, jibs are necessarily present in the design. Diagonal elements add rigidity and strength to the house, make the building durable and wear-resistant.
Appointment of jibs in frame houses
Residential frame houses are made like a multi-layered pie, and their walls have less structural strength than buildings made of brick, timber or logs. The load-bearing elements of the walls are located in the same plane and can change their position with strong winds, ground movement, and heavy rainfall. The presence of jibs allows you to stabilize the position of the structure, eliminate the risk of damage to the building.
Designing and building a house using frame technology without the use of jibs is not allowed. With this approach, the building has no other stiffeners, except for the corners. Even small external loads lead to damage to the outer or inner skin, loss of performance and attractive appearance.
In some cases, a cottage without jibs can "fold" like a house of cards without the possibility of recovery. Even if such a situation has been avoided, damage to the heat-insulating layer makes the building cold and windy, reduces its service life to a minimum. The presence of jibs completely eliminates such situations.
Features of mounting jibs
In frame housing construction, temporary and permanent jibs are used. Products of the first type are used only at the stage of building a cottage. With their help, they strengthen the corners, intermediate racks, set the elements according to the level until the end of the main installation stage. Before the start of finishing, the jibs are dismantled.
Permanent jibs are mounted taking into account the use during the entire life of the frame house. To give greater rigidity, the installation of structural elements is carried out not only in load-bearing walls. But also in internal partitions. When performing work, the following features are taken into account:
The optimum angle of inclination of the jib is 45°. It is allowed to increase it up to 60 °, for example, near window and door openings.
The mounting direction is determined from the center of the bottom tie bar to the top corner of the rack.
When arranging windows and doors, the jibs are directed from the corners to the existing openings.
Strong and reliable fixation is provided by the connection of the jib and the bearing element of the "thorn-groove" type.
The number of jibs on each wall is at least two, and their placement should be in close proximity to the corners of the building.
Solid, well-dried boards are used as the material. Otherwise, the wood will dry out over time with an increase in the gaps between the structural elements and a decrease in the strength of the frame. Our company builds houses with the obligatory fulfillment of these requirements, which guarantees high quality, reliability and durability of buildings.
Studs in a frame wallStabilizers in the frame wall stabilize the frame structure and prevent the house from folding. The first frame house designs in America were jokingly called balloons (balloon), as they gave the impression of a flimsy house that could blow away or break any gust of wind. Indeed, all racks, logs and other elements of the frame house are parallel or at right angles to each other. The only thing that can stabilize the structure is the introduction of an element that will be located at an angle.
As soon as a jib appears in the wall of the frame house, the structure stabilizes and can withstand the lateral force of the wind or earthquake. For early frame houses, girders or 45-degree (herringbone) planks on the outside of the house were the usual stabilizing elements of the frame. Today this is not the only solution:
1) Wooden jib. It is usually made from a board with a section of 25 x 100 mm. It cuts into the board of the lower and upper trim and passes at an angle of 45-60 degrees through the vertical posts. At first glance, the section of the board for the jib is not enough and there is a desire to take 50 x 100 mm or 50 x 150 mm, to be sure. But this is an extra expense of boards. An ordinary inch, which is cut into the harness and nailed to each rack with two nails, is enough. A classic rectangle is formed;
2) Metal jibs. Popular in North America. Low cost and high installation speed. It is enough to beat off the line with a chalk thread, make a cut and you can put a jib. The difference from the wooden one is that they must be placed crosswise. The fact is that the jib from the board works both in compression and in tension. The metal jib only copes with tension, therefore, in order to cope with loads that can come from different sides, a second jib is placed, which will also work in tension when the load vector changes;
3) External sheathing with plywood or osb. This is by far the most common way to stabilize a frame wall. The shape of the slab of the outer skin is rectangles, but in the frame wall they work like a classic triangle. The osb/plywood board is nailed to the upright and the bottom trim boards, forming the legs of a triangle. Nailed to the racks with a large step, the surface of the plate forms a diagonal.
There is no rule that assigns a rating to jibs and puts slabs or wooden jib first. The choice is made based on several factors. For example, for cold climates in Canada and the United States, polystyrene plates are used as outer skin, which cannot act as jibs. And then wooden or metal jibs are introduced into the construct. If siding is planned for the exterior, then plywood or osb boards are chosen, as they are an excellent surface for nailing the sheathing or the siding itself. By the way, no one forbids using two different types of jibs in one frame structure at the same time. For example, stud walls are lifted without cladding boards, which will only be installed after completion.
Ukosina - an inclined beam, the purpose of which is to support a vertical structure or part of it. In construction, they are used to increase the rigidity of the frame. Jambs in a frame house are installed to increase the stability and strength of the frame.
In Russia, frame houses began to be built after many years of their construction in America and Europe. Canadian and Finnish frame technologies have been formed. Extensive experience in frame construction has been accumulated. All mistakes, shortcomings and their impact on the operation of houses are summarized in the Rules or the Code. Some of its provisions have been translated and included in the Code of Rules for the Design and Construction of Frame Houses, in force in Russia. The vault allows you to use someone else's experience, build frame houses without errors from available materials. Unfortunately, in practice, the rules are distorted due to the desire to reduce the cost and simplify construction. The alteration takes place at the level of design, choice of materials, and construction itself. As a result, consumers have a misconception about the frame technology, the performance of such houses.
Racks, logs and floors are at right angles or parallel to each other. Without the use of special stabilizing elements, the house can "fold". Such an element is a jib, a bar installed and fixed at an angle to the uprights. A house with walls containing such reinforcing elements can withstand any gusts of wind, earthquakes.
Lack of jibs
Among Russian builders, the opinion has spread that jibs for a frame house are optional. Despite this, such an element of the foundation of the house is extremely necessary. Sheathing with slabs can replace them only when creating small household buildings. The absence of jibs for a residential building threatens with destruction, which begins with the deformation of the interior and exterior finishes, the displacement of the heat-insulating layer.
Expert opinion
Sergey Yurievich
Ask an expertIn frame houses being built at the beginning, jibs were not always used. Instead, the house was sheathed with boards set at 45 °, herringbone. Many years of experience have proven the unreliability of this method; it is used for non-residential buildings of a small area.
Ways to increase the rigidity of the foundation of the house
To increase the stability of the frame, apply:
- The wooden jib is set at an angle of 45 °. If adjacent walls, door or window openings do not allow maintaining just such an angle, it is increased to 60 °, sometimes more. The increase in angle should be compensated by installing more elements on the wall. For reliable stabilization of the frame, a board of 25 X 100 mm is sufficient, embedded in the boards of the upper and lower trim. The use of planks of a larger cross section leads to unreasonable costs for materials. The lower edge of the plank is placed closer to the center of the house, the upper - to the perimeter. Wooden jibs are strong, slightly weight the frame, withstand tensile and compression loads.
- Metal jibs are most common in North America, rarely used in Russia due to their significant weight and susceptibility to corrosion. They attract low cost and quick installation. Metal jibs are also cut into the upper and lower skins, but they are installed in a cross. This is due to the fact that metal strips can only withstand tensile loads and cannot withstand compression. The installation of two elements in a cross allows you to compensate for loads in any direction.
- External sheathing with plywood or oriented strand boards. Attached to the posts and boards of the lower trim, they form a triangle.
Which method to choose depends on the specific conditions: the area of \u200b\u200bthe building, climate, purpose, number of storeys. A combination of jib material is possible.
Expert opinion
Sergey Yurievich
Construction of houses, outbuildings, terraces and verandas.
Ask an expertStruts should not be confused with struts. Spacers have a different purpose, they are installed according to completely different rules. The spacer serves to eliminate the spring effect of the boards with a high wall height (from 3 m).
What does the lack of stabilizing elements lead to, their incorrect installation
An illiterate approach to the design of frame structures leads to a loss of strength and durability of the house. In the absence of braces in load-bearing walls and partitions, the structure cannot withstand even one year. They resist displacement, lateral loads. An engineering calculation is required, taking into account the maximum snow and wind loads.
What to consider when installing a jib
In order for the jib to reliably strengthen the frame of the building, when installing it, you must follow the rules:
- The plank thickness is up to one-fourth of the wall thickness.
- The jib is cut into the strapping boards and wall racks flush.
- At least two elements are installed on one wall in different directions: one tilts to the left, the other to the right.
- If the jib is installed before the wall is raised, in a lying position, then it is not worth fixing it rigidly, so that after installing the wall in a vertical position, the bar can be adjusted.
- It is more rational to install jibs on the inside of the wall from the point of view of the formation of cold bridges. From the outside it is more convenient to mount. The choice of the side of the wall does not affect the diagonal stiffness.
Temporary elements
Temporary braces support the walls after they have been erected until they are permanently fixed to the floor joists, and the sheathing is installed.