Creating heat in your own home is not entertainment, but an urgent need.
One of the stages of construction of the building, leading to this goal — insulation of floors. But in ready-made apartments and houses often need to insulate the concrete floor to create a more comfortable environment. Let’s move on to practical methods of floor insulation.
Calculated heat loss
As mentioned earlier, it is impossible to build a perfectly warm house. Therefore, the designers lay the value of the calculated heat loss. It depends on many reasons.
- Climatic features of the construction site
The minimum temperature of the coldest five-day period, the average temperature for the heating season and its duration, the average seasonal wind speed and its preferred direction, the humidity conditions of the construction area, the intensity of solar radiation during the heating period are taken into account.
So, for example, the minimum temperature of the coldest five — day period is taken as -28°C, the average temperature of the heating season -3,1°C, the duration of the heating season 214 days, wind speed in the coldest period 4,9 m/s, the rest of the time — 3,8 m/s, humidity zone-2 (normal).
- The architecture of the building
This refers to the space-planning solutions, the area of glazing, number of storeys, whether there are unheated basements and attics, the location of the interior. The heat loss of the corner room is higher than the room in the middle. If we take for example an apartment building, the apartments in the extreme entrances with two or more exterior walls “freeze” more than those that are protected from the cold street neighbors. All these factors affect the amount of heat loss.
To determine the allowable heat loss through the ceiling over an unheated basement shall take into account the proximity to the wall. That is, the entire floor area is divided into zones of width 2 m. For each prescribed value of heat transfer resistance. The area in the corners is taken into account twice.
Thermal resistance for different zones has the following values: I — R=2.1 W/(m°C); II – R=4.3 W/(m°C); III — R=8.6 W/(m°C); IV — R=14.2 W/(m°C). The total heat transfer resistance is summed.
- Geodesy
In addition to the climatic conditions of the area, to calculate the heat loss through the floor on the ground is important type of soil and groundwater level at the construction site.
- Structure of enclosing structures
Building structures are heterogeneous in their structure: they consist of different materials with different thermal resistance. Consider heat loss taking into account the thermal characteristics and thicknesses of all materials present in the design, including air layers, materials of interior and exterior finishing and through fasteners.
If there is no desire to go to such thermal details, it is possible to simplify to take advantage of any heat loss calculators on websites devoted to construction issues, and to consider average values derived for the standard design. For example, a thermal resistance of ceilings of non-insulated attic or basement shall be equal to 4,12 (recommended) or 3.3 (admissible). That is, the design of the floor, including insulation, should have a resistance to heat transfer within these parameters.
Knowledge of heat loss allows you to build a comfortable home for life, optimizing the choice of structural, insulation and finishing materials. This information will help you choose the heating equipment, as well as reduce the cost of subsequent operation (heating).
Methods of insulation of concrete floor
At all variety of heat-insulating materials of ways of warming of a concrete floor not so much. Two, actually.
Insulation under the screed
The essence of the method is that a layer of insulation is laid on the concrete (“black”) floor, on top of which the concrete screed is cast.
In this case, you can use a variety of materials: mineral wool, expanded polystyrene, polyethylene foam, sprayed expanded clay. Condition one: the insulation must have sufficient density to not deform from the load of the screed. Therefore loose mineral wool (for example, glass wool) will not work.
If the insulation is selected polystyrene (EPS) or rock wool, it is expedient to use the concrete mesh in the screed. Extruded polystyrene foam is quite dense and, in principle, can withstand the weight of the screed of small thickness, but it is better in this case to apply reinforcement.
For convenience of works it is recommended to fill in a layer of expanded clay with cement “milk”at first. So light balls stick together and will not float in solution.
The coupler does not bear so large structural loads, like a concrete slab. For it is permissible (and appropriate) to use lightweight concrete: foam concrete, polystyrene or other. This will facilitate the load, and will serve as additional insulation.
Insulation over joists
If it is assumed insulation concrete floor on the joists of a wooden Board or block, they are placed with a certain step, for example, 600 mm. In the cavity between the joists fit any insulation. In this case, the load of the coating layer will not fall on the heat insulator layer itself, but on the logs, so mineral wool of small density, eco-wool, loose insulation will suit.
After laying heat-insulating materials on joists plank subfloor of planks or sheet materials, which is then laid finish. If as a floor covering the massive Board is used, it is possible to do without a rough floor.
Do not forget about the vapor barrier insulation: over a layer of insulation material is left air layer, which can be saturated with moisture. If the vapor barrier is not provided, the moisture will be absorbed by the insulation, destroy it and worsen the insulating properties.
Insulation of concrete floor with thin-layer insulation
Heat loss (heat transfer) occur only when the temperature difference between inside and outside the enclosing structures. Therefore, in an apartment building (or on the second floor of private housing) may not be the task of increasing the thermal resistance of the concrete floor, because the temperature in the apartment below is the same as in yours. To just add comfort, fit thin insulation, such as cork sheets, PE foam rolls, sheets, fiberboard and others.
Warm floors and heat-insulated Swedish plate
All of the above options for insulation of concrete floors are passive: they prevent heat leakage. There is an active method of insulation, in which the floor not only resists the transfer of heat outside, but he warms. We are talking about the device floor heating-water, electric or other design.
Now the construction of low-rise residential buildings is gaining popularity is the concept of Foundation, floor insulation and heating system management using heat “in one bottle”. This concept is called insulated Swedish plate and is a Foundation in the form of a monolithic concrete slab with a good layer of insulation (extruded polystyrene) and a water floor heating under the entire area of the structure.
Also at the stage of Foundation in the concrete slab mounted all other utilities. Insulated Swedish stove significantly increases the energy efficiency of the house.
Choosing a method of thermal insulation and material for it, do not forget that to insulate the concrete floor is only 15% of the task of creating a warm home. Remembering the clothing allegory: if in January you went for a walk in a sweater, but in sandals and without a hat, the sweater, no matter how warm it was, will not save you from a cold. Insulate not only the concrete floor!