How to make calculations on the length of the pipe for a warm floor
Today it is difficult to imagine a country house without floor heating. Before you start installing heating, you need to make a calculation of the length of the pipe (calculator), which is used for a warm floor. Almost every country house has its own heat supply system, the owners of such houses independently establish a water floor if this is provided by the layout of the premises. Of course, you can also install such a warm floor in apartments, but this process can bring a lot of trouble for both apartment owners and workers. This is due to the fact that it is impossible to connect the floor heating to the heating system, and installing an additional boiler is problematic.
The size and shape of the pipe for a warm floor can be different, therefore, in order to understand how to calculate the warm floor, it is necessary to understand in detail the system and the structure of such a system.
How to calculate heat loss
On the correctness of this calculation, depends on the amount of heat that needs to be supplied to the room so that it was always a comfortable temperature. The calculations will help you determine the capacity of the floor heating, as well as help you make the right choice of boiler and pump.
To make such a calculation is very difficult. You have to take into account quite a few very different criteria:
- The time of year;
- The temperature of the air in the street;
- Type of room;
- Number and dimensions of windows;
- Flooring.
- Insulation of the walls;
- Where the room is located, downstairs or on the upper floors;
- Alternative heat sources;
- Office equipment;
- Lighting fixtures.
To make it easier to perform this calculation, we take average values. If the house is double-glazed and well insulated, this parameter will be approximately 40 W/m2.
Warm buildings with little insulation constantly lose about 70-80 W/m2.
If you take an old house, the heat loss increases sharply and is close to 100 W/m2.
In new cottages, where there is no insulation of the walls, where panoramic windows are installed, the loss may be about 300 W/m2.
Once you have chosen an approximate value for your room, you can begin to calculate the heat loss replenishment.
Power of the system
In order to determine the length of the water floor, it is necessary to calculate how much power the system requires to heat the usable area. For this there are special calculators, which laid the program calculations. Experts have derived tables. They indicate the norms of space heating with different heat losses.
Depending on these indicators install a floor line of a certain capacity. For 10 m2 you need 1 kW of energy. How to calculate the pipe for underfloor heating?
- To create a normal microclimate in the living room, the heating equipment must have a power of 120 W/m2. The same figure is maintained for a bedroom, a child’s room.
- Balcony and porch belong to the cold rooms with high heat loss, so provide for more power equipment, 150-180 W/m2.
- Rooms on the ground floor and basement level require 130 W/m2.
When calculating the capacity of underfloor heating with a calculator in the program enter data on the size of the room, the number of windows, ceiling height, duration of operation of the building. Information about floor, wall and roof insulation must be taken into account. Normal room temperature:
For efficient heating it is necessary to locate the water floor on an area of 70%. If the room is 64 m in size, its area will be 24 m2. 20% of the room is under stationary furniture. It is necessary to heat about 19 m2 of the floor. Place the floor heating pipes on an area of about 13 m2. If it is necessary to install a water main in the living room, the heating elements will require a power of 1560 watts.
How to make a floor heating calculation using water underfloor heating as an example
Many factors influence the efficiency of underfloor heating. Without taking them into account, even if the system is properly assembled, and the most modern materials are used for its arrangement, the real thermal efficiency will not meet expectations.
For this reason, a precise floor heating calculation must be the precondition for the installation work, and only then is it possible to guarantee a good result.
The development of a heating system project costs a lot of money, so many home handymen perform calculations on their own. The idea of reducing the cost of underfloor heating seems very tempting, don’t you think?
We advise you how to create a project, which criteria to consider when choosing parameters for the heating system, and describe the step by step method of calculation. For clarity we have prepared an example of floor heating calculation.
Electricity consumption
If it was decided to install the floor heating with a cable with electricity or a special infrared film, then you should first carefully calculate the electricity consumption. As a rule, electric underfloor heating can consume 250 W/h or even more per square meter of the entire system.
But it is worth remembering that energy consumption does not occur around the clock, but in cycles, i.e. first the floor is heated and then cooled. Also, the cable is not laid over the entire area of the room, but only in the middle.
After carefully analyzing everything, we can conclude that this type of floor heating provides maximum heat at a low power consumption.
The snail shape is ideal for large square, round or rectangular rooms. This includes mainly living rooms, kitchens, corridors, hallways, living rooms.
When the pipes are arranged in a snail-shaped coil, the heating is as uniform as in a snake-shaped coil. This is because the supply pipes, which have a hotter fluid, alternate with the return pipes, which have a slightly cooler fluid.
Laying out a large room in a serpentine pattern is not a mistake, just that one part of the room will always be slightly hotter than the other. This can cause discomfort. For small rooms it is not so critical.
If the laying area is geometrically complex, then use a serpentine, it will be easier to handle. It is also recommended to draw the project on dimensional paper beforehand to avoid confusion.
Calculation subtleties
In most cases, 5 m of pipe are used per 1 m2. In this case the pitch length is 20 cm.
However, experts recommend laying pipes based on accurate calculations. This will require the formula L=S/N1.1, where:
If you add the distance from the collector to the floor, doubled, you get a more accurate calculation. To better understand the calculations, you can give an example:
- Let’s assume that the area of the plot is 16 m2;
- distance from the collector to the floor. 3,5 m;
- laying spacing is 0.15 m;
- following the formula: 16 / 0.15 x 1.1 (3.5 x 2) = 124 m.
The increase in consumption depending on the distance between adjacent pipes is presented by the following table:
Pipe consumption per 1 m2, m. п.
Floor heating layout limits the length of the pipe to 120 m, because there are a number of reasons for this:
high temperature must not damage the floor covering;
heating in the circuit during operation (especially in case of leaks) can damage the cement screed;
the division of the surface into several sections contributes to efficient heating.
When carrying out the calculations, remember that the number of sections depends not only on the floor area, but also on its geometry.
By diameter
To correctly calculate the diameter of the pipe, the following calculations will be required:
15kPa is the pressure of the pump that provides efficient heating;
Therefore, the calculation is made according to the formula D=18 (p/LG2). 0.19, where:
CENTRAL HEATING SYSTEMS EXPLAINED. S Plan, Y Plan, One pipe, Two Pipe Underfloor Heating
D stands for the diameter of the pipe for underfloor heating;
The real cost of running hydronic floor heating vs. electric floor heating. Floor heating. Perth
G. the flow rate of water that circulates in the pipes (described in the documentation);
Manufacturers produce pipes 16 mm. the best option for installing the system. Suitable schemes for the configuration of the thermal floor are considered snake and snail. Hot water in the planning is red, cold water is indicated in blue.
According to the length of the circuit
A heating system needs a design that maintains the most effective pressure and air circulation. Therefore, the limit for the length of a water circuit is 80, maximum 100 meters. However, the room does not always fit the calculations, requiring its own parameters, sometimes in excess of 150 m. The problem is solved easily. just install a few loops.
Underfloor heating pipe and how to calculate how much you need
For example, if the room requires 240 m of pipe, you should create three structures of 80 m. At the same time, the circuits do not have to correspond to each other. According to experts, the difference can be up to 15 meters.
In the calculations it is necessary to take into account the diameter of the pipe and the material of manufacture:
Metal-plastic products are most in demand due to low cost and easy installation. It is based on polyethylene with an aluminum layer, which increases the reliability of the construction. Metal has a high thermal conductivity, which attracts manufacturers who want to create optimal conditions of heat exchange. With a diameter of 16 mm, the length of the circuit can reach hundreds of meters.
Polyethylene constructions do not require an additional layer, cross-linking at the molecular level. The product is easy to bend, showing resistance to high temperatures up to 95ºC and to various chemical solvents. At 18 mm diameter, the limit is 120 meters.
Polypropylene has high stiffness and strength. It is not in demand in the market and is used mainly for manufacturing purposes. The length limit for the product is 90-100 meters.
Copper products have the highest thermal conductivity, due to which their price is the highest in the construction market. However, they need professional installation, because they leak at the slightest fault.
Corrugated pipes are made of stainless steel. The maximum length of the circuit is equal to 120 m with a diameter of 25 mm. Corrugated pipes are recommended to buy with the calculated in advance length, sufficient for one circuit. Such a purchase automatically eliminates the possibility of leakage.
The construction selection must be based on the room conditions. Otherwise the number of circuits must be calculated.
A larger area should be divided into constituent areas at a ratio of 1: 2. That is, its width will be half the length. Consequently, in order to calculate the number of sections, you will need the following measures:
With a pitch of 15 cm the number of m2 for the area of the plot does not exceed 12;
If you subsequently increase the pitch by 5 cm, the area correspondingly increases by 4 m2. However, experts do not recommend calculating exact values. In order to avoid leaks, a reserve of 2 m2 should be taken.
Parameters for the calculation of the heating circuit
At the design stage it is necessary to solve a number of issues that determine the design features of the floor heating and operating mode to choose the thickness of the screed, the pump and other necessary equipment.
Technical aspects of the organization of the heating branch largely depend on its purpose. In addition to the purpose, to accurately calculate the meterage of the water loop will need a number of indicators: the area of coverage, heat flux density, fluid temperature, type of flooring.
Covering area with pipes
In determining the size of the basis for laying pipes in the account space is taken, not cluttered with large appliances and built-in furniture. It is necessary to think in advance about the layout of objects in the room.
Heat flow and coolant temperature
The heat flux density is a calculated index that characterizes the optimal amount of heat energy to heat the room. The value depends on a number of factors: the thermal conductivity of the walls, floors, the area of glazing, the presence of insulation and the intensity of air exchange. Based on the heat flux, is determined by the step of laying the loop.
The maximum temperature of the heat carrier. 60 ° C. However, the thickness of the screed and floor coating knock down the temperature. in fact on the surface of the floor is about 30-35 ° C. The difference between the thermal indicators at the input and output of the loop should not exceed 5 ° C.
Type of flooring
The final finish affects the efficiency of the system. Optimal thermal conductivity of tiles and porcelain tiles. the surface warms up quickly. Good water loop efficiency with laminate and linoleum without insulation layer. The lowest thermal conductivity of wooden surfaces.
The degree of heat dissipation also depends on the material. The system is most effective when using heavy concrete with natural aggregate, such as sea pebbles of a small fraction.
When calculating pipes for underfloor heating, the established norms for the temperature of the covering should be taken into account:
- 29 ° C. the living room;
- 33 ° C. rooms of high humidity;
- 35 ° C. the passage zones and cold belts. areas along the end walls.
Important to determine the density of the laying of the water circuit play an important role climatic features of the region. When calculating heat loss, you need to consider the minimum temperature in winter.
As practice shows, to reduce the load will help to pre-insulate the entire house. It makes sense to insulate the room first, and then proceed to the calculation of heat loss and parameters of the pipe circuit.
Underfloor heating calculation program
In the first method of calculation using dimensional paper, pencil and eraser.
On paper, the area of the room is drawn, with all the preliminary data and with the help of formulas the calculation is made. This method is more accurate, but it takes a lot of free time and requires special skills. Therefore, for a faster calculation of floor heating, the program is used to calculate the floor heating. online calculator.
The essence of this method is that all the data are entered into the calculator online, with the necessary dimensions and choices, which are already set in it. Then, when you click on the total, the calculator outputs the results.
To calculate the number of pipes, you can also use various computer programs that make it easier to determine the length of the materials. For example, the VALTEC floor heating pipe length calculator (program is free, it can be found here).
The correct calculation is the key to the installation of optimal floor design. It is desirable that the calculation be carried out by qualified specialists, who, having determined all the conditions, will be able to calculate the optimal parameters. If you install the flooring by yourself, it is recommended to use a computer program for the calculation.
When all the results are ready and you can begin to install the water heated floor, you should familiarize yourself with a few nuances.
