Depending on the scale of the structure and the type of home ceiling do either of slabs or use a more simple economical form – beamed ceiling (great for private homes).
Beams – structural elements of the house necessary for reception and distribution of various types of loads: the roof and located above the floor and to separate the house on the floors.
Location the house floors are distinguished:
- ground floor,
The upper part of the beam is usually floor for the upper room, the bottom plays the role of a ceiling for the room below. All types of ceiling has its own characteristic nuances, so the cake attic floor always includes layers of heat and vapor barrier, and floor decks for a more important layer of insulation.
The essence of the beams
Floor beam – mounted legs straight supporting structure with a horizontal or inclined position. All get the loads from the beams are transferred to the supports, which may be walls, columns, and spread between other structural elements of the building.
Requirements for the beams
Proper arrangement and selection of sizes, types, step beams require certain knowledge and practical experience. Standard procedure for the design of beams is a complex of certain calculations, girders:
- the calculation of the beam strength (the load on the attic floor up to 105 kg/m2; backboard not less than 210 kg / m2). To be safe mOU can calculate the beam on the standard. load 400 kg/m, adding the load weight ceiling
- check rigidity - calculation of the deflection of beams where the calculated value must be less than limit values:
We offer to calculate use our calculator beams online.
The strength characteristics and the potential of load beams depend on the following factors:
- The material of a beam
- The area and shape of cross-section
- Mounting method
Private construction demand especially beams of wood, combining high strength, reliability and ease of installation. Steel, reinforced and composite variations are utilized generally in industrial construction and in the arrangement of the objects on which it is anticipated an increased load on the beam.
Types of beams the advantages and disadvantages of
They often choose a ceiling in wooden houses, timber, brick houses and the houses built of silicate blocks for roof slabs, and also in cases, if you want to save money on materials, or if the capacity of the Foundation is not designed for heavy overlap between floors, as well as in unstable soil area.
The main material used for beams such variations – wood non-coniferous, carefully dried and subjected to special treatment to improve its performance and technical parameters. Such beam ceiling includes direct beam, insulation, traction and floor.
- The convenience and ease of installation;
- Reasonable cost;
- The low weight of the product.
- The high level of Flammability;
- Vulnerability to lose the bark beetle;
- The possible decay of the structure over time;
- The floor structure on wooden beams is applied only to the fourth floor.
To simplify the calculation of wooden beams and of choice for its cross-sections and pitch, we provide a table that will help you to make a pre-selection of cross-sections for single-span wooden beams. You only have to collect standard load:
When installing wooden beams laid on the transverse supports, which can serve as an additional Board, or nets, flooded along the perimeter masonry walls. The transverse support serve to evenly distribute the load on the wall, and then on the Foundation of the house. Of the beams laid on the walls, wrapped with waterproofing material. Usually use roofing felt, with the ends not isoleret that allows the beam to "breathe".
In particular the construction of a common practice - the use of monolithic concrete slabs, or other types of the most durable floors on the lower floors of buildings, and the simultaneous use of joists for timber beams on the higher floors - for example, the attic. This is done to facilitate the total load on the Foundation from all floors, walls, roofs and contents of the house.
The most important thing when choosing a material for floors on wooden beams - carefully select high-quality wood without cracks, damage, well dried, impregnated against fire and rot, and also suitable for building design beam cross-sections.
Metal beams made of high strength steel alloy according to the technology of hot or cold riding. Structurally presented in the form of steel channel, angle or I-beam, I-beams thus have the highest demand and popularity. Installation is possible as "flat", and on edge.
- The arrangement spans of greater length than the beams made of wood;
- Resistance to biological nature and decay.
- Possible corrosion;
- Low sound and thermal insulation parameters.
Reinforced concrete beam
Reinforced concrete beams are the optimal choice for large-scale construction, it can withstand substantial external loads at great length, equip span. Load parameters are presented at a very high level.
- The lack of deflections;
- Increased bearing capacity;
- The formation of long spans with different shapes.
- The complexity of the installation;
- The need for involvement of specialized equipment.
The combined beams
The combined beam is made on the basis of several materials, such as wood and OSB. Their use is common in private frame construction. Products can take various forms, but the greatest prevalence is the combined I-beam, can effectively resist various external loads, withstanding even considerable stresses.
- Excellent strength data;
- Resistance to deformation;
- Minor weight.
- High price;
- The inconvenience of insulation Board material.
Technical characteristics – how to avoid mistakes when choosing
Wooden beams is effective in the closure of the span of 2.5 – 4 m. Maximum length is 6 m, the greater the length, can not do without installation of support columns or other structures.
Mount the rafters to the joists of wood is carried out by means of steel plates, angles, and sliding supports. When determining the cross section for the standard take the total load of 350-400 kg/m2 for reassurance. The optimal ratio between the height and width of the product is 1.4:1. The required length of the wooden ceiling beams is determined by the size of the span they can cover, additionally you need taking into account the size of the spades on the wall - not less than 12 cm, for a bar - at least 15 cm.
Board width for beams in the range of 4-20 cm, height of 10-30 cm, the diameter of the logs can reach 11-30 cm depending on the dimensions of the beam spacing is 0.3-1.2 m (typically 0.6 to 1 m).
The distance between the beams of metal in the range of 1-1,2 m. Number (size) of the beam at a load of 400 kg/m2 is chosen based on the length of the settling of the span and step of installation. So, when the span is 6 m and the step 1-1,2 m 20 optimal I-beam (height 20, width 10 cm); the span is 4 m, the step 1-1,2 m - n 12 (height: 12, width 6.4 cm); span 3 m, step 1-1,2 m No. 10 (height: 10, width 5.5 cm).
Modern concrete floor beam is able to close the gap with a length of 3-7,5 m, and the laying is carried out in increments of 1-1. 5 m. the Minimum height of an element is 1/20 of the span length, the width is calculated based on the proportion of 5:7 (5 - width 7 - height).
The dimensions of the floor beams of the combined type can be very different. For W series maximum length is 6 m, the category of L provides the length to 13.5 m. the Main difference between the groups is the type of timber. In the first case it scraped a product that has been drying chamber, and the second laminated beams, United of the individual elements through a special technology, which gives the final product greater rigidity, durability and reliability.