- Basic floor composition
- Underlying layer
- Thermal insulation
- Floor with underground. Its composition and structure
The floor on the ground in a private house, made by hand according to the recommendations of specialists, is strong and durable. A smooth, non-slippery surface and low thermal conductivity are also quality indicators. Each layer in the floor structure has its own purpose and it is very important to observe the technology of its construction.
In a private house, most often the floor is arranged on a ground base. The main requirements for the construction of the floor of a dwelling are:
- Low thermal conductivity.
- Wear resistance.
- Fire safety.
- Economy of building materials.
- Low labor intensity.
- Operational safety.
The floor device assumes a positive room temperature, which must be at least 5 ° C, depending on the characteristics of the floor composition.
Important! Do not lay the floor on a frozen base.!
Basic floor composition
The composition of the floor depends on:
- the purpose of the premises;
- operating temperature and humidity;
- type of soil base;
- floor technology;
- coating design solution.
Floor cake on the ground: 1 – compacted ground; 2 – sand and gravel mixture; 3 – concrete bedding; 4 – vapor barrier; 5 – thermal insulation; 6 – plastic film; 7 – reinforced screed
The base for the floor is the soil that lies directly under the floor. Its purpose is to withstand the load on the floor, including its weight, without deforming the soil structure..
It is very important that there is no groundwater directly under the floor. Its level decreases when drainage is installed around the house. You can protect the floor from water by increasing the underlying layer of coarse materials (sand, crushed stone or gravel), or by using waterproofing made of synthetic materials under the concrete preparation.
If bedding is necessary, then it is performed with non-porous soil. Filled soil is compacted without fail. The soil layer must be removed to its full depth. Weak soils are either replaced with low-compressive soils or compacted to prevent floor subsidence.
The heaving soil under the floor can be partially replaced with non-heaving soil, or the water table can be lowered. The floor must not be laid on organic soils (peat, black soil, etc.). They are also replaced, for example, with sand or sand and gravel mixture..
The surface of the base under the floor is leveled and compacted. It is possible to compact the soil by sinking a layer of rubble or gravel 5–8 cm thick into the base at least 4 cm deep.
The purpose of the sub-base is to distribute the load from the floor over the subgrade. Its minimum value is taken:
- sandy – 60 mm;
- crushed stone, gravel, slag – 80 mm;
- concrete – 80 mm.
Gravel (crushed stone), sand and gravel or sand preparation must be leveled and compacted. For a private house, its thickness is 10-15 cm.
Concrete preparation (concrete grade over B7.5) should be laid in strips 3-4 m wide using lighthouse boards. The concreting of the strips is carried out through one strip with a time interval of 24 hours. Freshly laid concrete must be compacted.
Under the concrete preparation, a backfill is made of coarse sand, gravel (crushed stone) with a thickness of 12-15 cm, which is compacted to the entire depth. Asphalt concrete preparation is laid in layers of 40 mm. The lower layer is coarse (binder), and the upper layer is cast asphalt concrete.
The screed is the basis for a clean floor. Its purpose is:
- distribution of the load on the underlying layer;
- leveling the base under the coating;
- device of slopes in the floor, if necessary;
- creating a heat-insulating layer (lightweight concrete);
- the ability to hide communications.
The concrete for the screed along the heat insulator layer is taken with a class of at least B15, the cement-sand mortar must have a compressive strength of more than 20 MPa. In addition to leveling the surface of the previous layer, lightweight concrete screeds also play the role of thermal insulation. In this case, the class of concrete is allowed at least B5. Insulation screeds made of porous cement-sand mortar must have a strength of at least 5 MPa in compression.
The thickness of the screed in the case of sheltering pipelines in it is taken 4.5 cm more than the diameter of the pipe. The minimum thickness of screeds made from self-compacting mortars using dry floor mixes on a cement binder should exceed the maximum filler size by 1.5 times.
The semi-dry method of laying the screed on a cement binder significantly reduces the time of mortar hardening and increases the strength of the layer. A low water-cement ratio of the mixture requires compulsory compaction of the freshly laid mortar and surface grinding. Fiber in the composition of the mixture as a “mini-reinforcement” increases the strength of the floor, including its entire surface in joint work.
With a high indicator of the water-cement ratio of the cement-sand mixture, its self-leveling occurs. The disadvantage of such a layer is the increase in the hardening time of the screed. Highly plastic screeds are recommended to be arranged over a layer of dry heat-insulating material.
The solution, seeping into the spaces between the insulation particles, binds them and creates a layer of lightweight concrete on top. This process strengthens and evens out the insulation layer. The minimum thickness of such a screed is taken 5 cm.
For a dry screed device are used:
- Fibreboard (fiberboard);
- GVL (gypsum-fibrous sheets);
- DSP (cement-bonded particle boards);
- Chipboard (chipboard);
- GSP (gypsum board), etc..
Dry floor screed
Such a floor can be arranged only in rooms with a dry mode, while it is necessary to reliably protect the screed from getting wet.
The following are used as thermal insulation of the floor on the ground base:
- Lightweight concrete (expanded clay concrete, foam concrete, slag concrete, etc.).
- Bulk insulation (expanded clay, expanded vermiculite or perlite, granulated slag, etc.).
- Plate and roll (mineral wool, expanded polystyrene, foam glass, etc.).
The choice of insulation depends on the choice of floor construction, in particular, its coverage.
Waterproofing for floors on a ground base is required:
- to protect it from groundwater;
- to protect the heat insulator from moisture from the coating surface.
It should be continuous throughout the floor. The number of layers depends on the type of waterproofing:
- for bituminous and bitumen-polymer mastics, cement mortars, bituminous roll materials glued to bituminous mastics – at least 2 layers;
- for overlaid bitumen, self-adhesive, polymer roll materials – at least 1 layer.
The surface of the bituminous waterproofing is prepared before applying interlayers, screeds, coatings with a cement binder, sprinkling with sand with a particle size of 1.5–5 mm. You can also use a ready-made roll-on waterproofing with surface dressing..
In addition to roll waterproofing materials, bulk insulation is used, which impregnates the preparatory layer of bulk crushed stone (gravel) with bitumen. It is used as a waterproofing asphalt concrete, as well as rolled profiled polyethylene membranes. It is important that the waterproofing of the floor on the ground is combined with the waterproofing of the foundations as well as the walls..
The surface of the clean floor must be non-slippery, safe in its composition, wear-resistant, fireproof and even. The last condition is checked by the size of the gap between the control two-meter rail and the floor surface:
- from boards, parquet, linoleum, polymer mastic floors – 2 mm;
- concrete, xylene, ceramic, porcelain stoneware floors – 4 mm.
Gaps for piece coating are allowed:
- between the planks of the plank floor – 1 mm;
- between parquet floor boards – 0.5 mm;
- between the planks of a piece parquet floor – 0.3 mm.
For carpet, gaps between the panels to be joined are not allowed. For tiled and block flooring, the width of the seams is taken no more than 6 mm, if the tiles are laid manually on the layer.
Adhesives for attaching the coating to the substrate must meet the peel strength requirements of the coating material with the previous layer. The thickness of the interlayer is also standardized.
Floor with underground. Its composition and structure
An example of a ground floor is an underground floor. On a compacted soil base, posts made of concrete or clay bricks are installed. Their size in the plan is 25×25 cm.The brick grade is taken at least 75, the mortar grade is at least 10.
For concrete pillars for concrete logs, grades of at least 75 are used. The distance between the axes of the pillars at a load not exceeding 400 kg / m2, is 1.1-1.4 m.
The height from the ground to the subfloor in the underground should not exceed 250 mm. 2 layers of roll waterproofing are laid on brick posts.
To determine the size of the lag, it is necessary to consider:
- span (distance between supports along the axis);
- the thickness of the insulation;
- the height of the cranial bars;
- the thickness of the subfloor;
- the gap between the clean floor and the upper edge of the insulation – min. 3 cm.
1 – beam; 2 – cranial bar; 3 – rough floor; 4, 6 – vapor barrier; 5 – thermal insulation; 7 – floor board
The size of the cranial bars is 40×40 mm. A mineral wool board can be used as a heater. Roll materials (bituminous, polymer or polymer-bitumen) are used for waterproofing. All wooden floor elements must be antiseptic.