When building any house, special attention should be paid to the overlap of the beams. The floor structure may consist of slabs and beams, which are wooden, concrete or metal. The most important thing to consider is the way such supports are supported on a brick wall, since the construction of brick houses is considered the most common. The support of the beam on the beams and the wall in the designed building will be the most important element, since it will determine the reliability of the structure and the safety of its operation.
What are beams used for?
They are not only a support for flooring and interfloor passages, but also help to fasten all the details of the structure together, giving them the necessary strength and reliability. In the manufacture of beams, a large number of different ceilings are used. But the main and most common types of load-bearing elements should include metal, wood and reinforced concrete.
Wooden beam and its distinctive features
Beams to support beams and walls made of wood must comply with basic building codes, andnamely, to be strong, rigid, and also to comply with fire safety rules. The calculation of such an element is carried out depending on the material used in the construction.
Beam is an important part of any floor. Its main function is to separate the floors of the house, as well as to evenly distribute the load on the upper walls, the roof of the house, communications, and furniture in the room.
The main advantages of supporting wooden beams:
- minimum labor intensity during installation installation (when compared with metal and reinforced concrete structures);
- affordable wood cost;
- possibility of self-assembly without the use of expensive machinery and other construction equipment;
- attractive appearance;
- light weight;
- the possibility of replacing or restoring them.
Disadvantages of wood structures
The main disadvantages of such bars include:
- high degree of ignition (to prevent sudden ignition, it is necessary to treat the material with a special protective impregnation);
- compared to metal and reinforced concrete counterparts, this design is fragile;
- on the wooden material, the active spread of fungus, living organisms can begin, moisture can easily penetrate into it;
- wood is prone to deformation under the condition of regular temperature changes in the room.
What types of hardwood floors are there?
Wooden floor beams can be classified according to their section type, size and material used to make them. Its length will directly depend on the distance between adjacent walls. To this value, an additional 200-250 mm is added on each side.
By the type of section, all structures can be divided into the following types:
- rectangular;
- I-beam;
- square;
- oval or round.
The square section of the beam is considered optimal, since it is it that helps to achieve the most even load distribution over the structure. Also, builders recommend choosing wooden floors with a rectangular section. When mounted, their short side is placed horizontally, and the long side is placed vertically (for good strength, it is important to increase the height of the structure).
Material and features of the overlap
Overlapping is the connection of a beam with a load-bearing building wall, which can be attic, attic or interfloor. Structurally, they are divided into two types: prefabricated (transverse flooring and longitudinal beam), as well as monolithic (support is carried out on a slab).
When designing private structures, more preference is given to ceilings with wooden beams. This design is considered quite durable and well suited for the residential sector. The optimal size of the support, depending on the purpose of its use and the applied loads, will vary:
- height - from 150 to 300 millimeters;
- width –from 100 to 250 millimeters.
In order to increase the service life, the supports are impregnated with a specialized antiseptic and also oiled.
In more complex structures, they resort to leaning on metal beams. For this, construction companies create special strong steel supports. According to safety regulations, when using beams of this type, their ends must rest on the brickwork through specialized distribution pads.
Monolithic ceilings are made of reinforced concrete slabs. For this, it is customary to use factory-made slabs of reinforcement and concrete mass. In order to reduce the load on the finished structure, they are created hollow.
How is the beam embedded?
The reliability and quality of the floor will be largely determined by the method of embedding the beam into the wall. The termination will determine the type of support on the brick wall - it is this stage of mounting the structure that is the main one.
The wooden beam is mounted in the free space created in the brickwork, up to 15 centimeters deep. The end ends are pre-processed: one end is cut off at an angle of 60 degrees, treated with a special antiseptic and resin, wrapped with roofing felt or roofing material. The processed ends of the beam are carefully installed in a brick wall with a gap of 3–5 centimeters from the back wall of the niche. The formed gap is filled with felt or mineral wool. The transverse faces are carefully sealed with a concrete mixture, bitumen or coated with roofing paper.
Leaning on a brick wall
When supporting a beam on a brick wall, it is important to pay special attention to the thickness of the structure. If the thickness of the brick wall is more than 600 millimeters, then the termination method will be slightly different. This space in the masonry is created so that between the end of the beam and the back wall of the niche there is a free space of at least 10 centimeters. The resulting gap helps to lay the material for thermal insulation in it and allows you to create a special air gap.
The lower part of the gap is sealed with concrete, roofing material or roofing felt in several layers. With the help of this technology, it is possible to create a laying pillow, which, among other things, additionally levels the surface of the masonry. The sides of the resulting recess are treated with roofing paper.
Relying on a thinner wall: advice from builders
When creating a ceiling supported by a wall up to 500 millimeters thick (two bricks), the termination method should be slightly different from the previous one. A wooden box with several walls is placed in free space (its depth is not more than 250 millimeters). A tarred layer of felt is laid between the back wall of the niche and the box. The walls are carefully treated with anti-combustible compound and resin.
At the bottom, the recess should be sealed with two layers of roofing material or roofing paper. The side walls of the nest must be insulated with felt. The box is built into the free space so that it is pressed tightly against the felt. The floor beam is installed on the bottom of the box for a length of 15 centimeters.
If the thickness of the wallless than the specified mark, then it is important to pay special attention to the total wall thickness that remains after creating a free compartment. If it is less than 50 millimeters, there is a risk of free passage of cold air into the room. If there is such a problem, it is important to consider additional insulation of the area where the beams are supported on the beams and the wall.
Implementation of beam mounting
The installation of a support when creating a floor will directly depend on the further purposes of using the structure, the area and the load falling on it. Most often, a wooden beam is installed along load-bearing walls at a distance of 600 to 1500 mm.
Sealing starts from the edges with the subsequent transition to the entire length of the wall. Between the extreme beams and the wall itself, builders recommend leaving a free space of at least 5 centimeters.
Another rather important condition when supporting beams on a beam and a wall is to take into account the horizontal fastening of the support. In addition, all the bars should be evenly spaced in relation to the floor. Deviation from the horizontal and uneven level will lead to additional loads on the area of \u200b\u200bsupporting the brick wall, especially after installing additional transverse beams.
Leaning on a column
It can be hinged or rigid type. Builders advise supporting the beam from above and transferring the main load to the center of the column profile. When lateral fastening of the structure, in addition to the compressive load, in the column additionallythere is a moment from the action of this force. This provokes a significant increase in the load from the column.
When supporting a metal beam on a column from above, it is best to transfer the load to the rib. The rib size will be determined using the following formula: F/Ap greater than or equal to RpYc.
- F in the presented formula is the support force of the beam;
- Ap – bearing rib crushing area;
- Rp is the design resistance of the steel to the collapse of the end surface.
In order for the entire load to pass to the column through the rib, the rib protrusion should be observed, as a rule, by 1.5–2 centimeters. It is important to carefully cut the rib before installation, which will help distribute the entire load evenly over its area.
Since the support unit of the floor beams is of the hinged type, only a few bolts on one side are enough for fastening. Bolt diameter from 16 to 20 mm. They should not be over tightened. Support thickness is usually 0-25mm, rib thickness is 8-12mm.
If there is a roof angle in the design, then the rib should be cut at the required angle and take washers with a bevel to mount the bolt.
Beam support norms
The regulatory documents set the minimum length of beam support on a beam and a brick wall - it reaches 9 centimeters. This value was determined by design engineers as a result of lengthy calculations and checks. The following factors affect the minimum beam support:
- span size and support length;
- load amount per applied beam;
- load type - dynamic or static;
- thickness of the brick wall on which the support falls;
- type of building - private residential, industrial, etc.
All the factors described must be taken into account when making calculations. The end of the beam must overlap the wall so that the resulting overlap does not exceed 12 centimeters.
