The decision to independently organize floor heating with the help raises the question: “How to design and install a warm water floor with your own hands?” This system is quite difficult to install. But this “complexity” is compensated by further ease of use and more comfortable heating of the room, in comparison with radiator heating. You can reduce the cost of installing a warm floor by excluding the services of qualified craftsmen from the work process, that is, at your own peril and risk, take the entire installation process into your own hands. It is necessary to correctly calculate, select and purchase the necessary materials, prepare the floor surface for the installation of the heating system and ... just do it!
What is a warm water floor?
A warm water floor is a variant of today's popular heating systems. To properly install a water heated floor, you need to have basic information about the installation of water systems and know the "pitfalls" of such a process. After all, apparent simplicity in practice turns into a mass of interrogative and problematic situations, which, with experience, could be foreseen in advance.
The principle of operation and the device of a water heated floor is quite simple - the heat carrier heated by the boiler to a certain temperature circulates through a special pipeline mounted in the floor of the room, transferring heat from the heat carrier in the pipes to it.
Calm down! Our negative experience of knowing cases of leaks in heating systems inspires fear, what if a leak appears? What's with the floor?.. What's with the neighbors? What words can be heard from them in such a situation?
Today's "advanced" technologies offer at the service of people such special pipes for underfloor heating, which (with proper installation) virtually eliminate the possibility of damage to the pipeline in the floor!
List of required materials
A reliable device for a warm water floor involves the use of high-quality component materials, a list of which is desirable to be compiled in advance and purchased one-time, so as not to “roll” kilometers to the nearest or profitable construction supermarket.
Here is a sample list of required materials:
- Means of thermal insulation: polystyrene foil mats or extruded polystyrene foam boards (for heavy floor loads).
- Damper tape (self-adhesive) 5 to 10 mm thick.
- Reinforcing mesh (Fixes the screed, but can also be used for mounting a heating pipe on it).
- Metal-plastic or polyethylene pipe (What to choose? How to calculate? Read below!)
- Fixings for pipes (brackets, mounting strips, swivel arcs, etc.)
- Additional ingredients in the concrete floor mix (plasticizers, fillers, etc.)
- Collector systems (combs) for connecting the circuit (s) of the underfloor heating system. As well as a cabinet for their "aesthetic" installation.
We prepare and insulate the surface under the water-heated floor
Before making a water heated floor, we are preparing a “bridgehead” for installation work, namely, to optimize the state of the concrete base on which pipes for a warm water floor will be mounted.
3.1 The old screed, if any, is dismantled to the ground.
3.2 The base of the floor is leveled strictly horizontally - height differences of up to 10 mm are eliminated.
3.3 By laying waterproofing material, waterproofing of the base is carried out. In a multi-storey building, for example, such waterproofing will relieve you of the need to make repairs to the neighbors below, if the warm floor suddenly “leaks”. In a private house or on the ground floor, such waterproofing will be a serious obstacle to the slow but “sure” penetration of moisture (dampness) from the ground into the thickness of the concrete screed of the warm floor.
3.4 A damper tape is glued along the perimeter (along the walls), designed to further compensate for the thermal expansion of the concrete screed when the floor heating system is heated.
Note! Underfloor heating can be installed using several "zone" circuits in one room. This allows you to differentially set the temperature regime in different parts of the room. If there are several circuits, a damper tape is also laid between them.
3.5 I hope you are planning to heat your floor, not the neighbors ceiling or the ground under the house. If this is the case - take care of the insulation of the base of the floor.
Floor insulation is performed in several ways, based on the location of the room and the type of heating in it.
- The premises of the first floor, located on the ground or above an unheated basement, should be insulated "seriously": for example, sheets of expanded polystyrene (thickness from 50 to 100 mm) laid on a layer of expanded clay.
- The floor of the apartment, with the neighbors below, will be enough to “cover” with sheets of extruded polystyrene foam (20-50 mm).
- In the case of using a water-heated floor as an addition to the heating radiators in the room, it will be enough to lay a layer of foiled (foil up) foamed polyethylene (penofol).
An interesting opportunity! If there are sufficient funds, to optimize the thermal insulation process, you can use specialized insulation mats with already prepared channels for laying pipes in them.
3.6 The next step is to fix the reinforcing mesh, designed for "anchor" fixation of the concrete screed covering the floor heating pipe system.
Attention savings! The pipes of the heating system can be attached to the same reinforcing mesh with ordinary plastic clamps-screeds. This will save some money by excluding fasteners for underfloor heating pipes from the shopping list.
Let's look at the "peripheral" fragment of the section of the "pie" of the warm floor:
Design and calculation of underfloor heating parameters
Pipes
The best option for underfloor heating is polypropylene or cross-linked polyethylene. The cost of installing a water heating floor when using polyethylene pipes will increase slightly.
When using polypropylene, it is desirable to choose pipes reinforced with fiberglass, since polypropylene itself has a significant coefficient of thermal expansion. Fiberglass "reinforcement" prevents the expansion of the polypropylene pipe, which in turn has a positive effect on the quality of the concrete screed underfloor heating.
Pipes made of cross-linked polyethylene are widely used today and have a less "significant" temperature coefficient of expansion.
Pipe size - diameter 16-20 mm.
The maximum heating temperature is at least 95 ° C.
Maximum pressure - not less than 10 atm.
Collector system
The design of a water heated floor when using more than one floor heating circuit involves the use of a manifold cabinet with all the necessary devices for connecting and controlling floor heating circuits.
Collector- this is a metal pipe-"comb" with nozzles for connecting the circuits of heating devices. The collectors are designed to provide the possibility of differentiated regulation of various heating circuits.
Collectors are equipped with either shut-off or control valves. Shut-off valves are intended only for completely disconnecting the heating circuit from the system (cheap, but inconvenient), and adjusting valves allow you to smoothly change the supply of coolant to the heating circuit.
Be sure to have an air valve in the manifold, as well as a drain outlet.
A manifold group is assembled in a manifold cabinet, which usually consists of two (supply and return) "combs", on which the necessary valves are mounted.
The collector cabinet must be designed when developing the entire heating system of a house or apartment. It is desirable that this be a place evenly removed from all heating devices, usually in a wall niche just above the floor level. The collector is selected based on the number of heating circuits connected to it.
The collector cabinet MUST be installed above the level of underfloor heating. Pipes should only go down from it - otherwise the air exhaust system will not be able to function normally.
Attention! - Why is it so difficult? - you ask. And you will be right. The collector group is not cheap and ... If you use one underfloor heating circuit and do not want to "complicate" the system at additional costs, you can install water-heated floors to the main pipes using "tees" with the obligatory installation of control valves on the supply and return pipes.
In the collector group, you can install a thermostat for a water-heated floor. There are manifolds with electromechanical servo valves on valves that allow you to fully automate the "climate" control of underfloor heating and heating radiators throughout the house. The special preliminary mixers installed in them supply already mixed hot and cold water to the underfloor heating circuit to provide the required heating temperature. Installing such systems in a private house, where the heat loads on various heating circuits do not fluctuate sharply, is impractical (The cost of a warm water floor at this age is instant) even if you install a warm water floor with your own hands.
Calculation of underfloor heating pipes
How to calculate a warm floor for its efficient operation? After all, for each room it is necessary to make an individual calculation of the heating circuits. To do this, you can use specialized computer programs or the services of design organizations available to you.
Incorrect calculation of a warm water floor or complete disregard for it (installation of the system “by eye” and even without experience of such work) can lead to the appearance of a thermal “zebra” on the floor (alternating warm and cold zones), uneven heating of the floor in the room, heat leakage into cold uninsulated areas.
Parameters taken into account in the calculations:
- linear dimensions of the room;
- material and the presence of thermal insulation of walls and ceilings;
- type of heat-insulating material under the warm floor;
- type of floor covering;
- material and diameter of pipes of the underfloor heating system;
- temperature of the "incoming" water (depends on the capacity of the boiler of the heating system).
Based on these parameters, the length of the heating circuit, the pipe pitch, as well as the layout of the pipe in the concrete screed are determined (More on this below). These parameters will determine the heat transfer power of the floor of the room.
Installation methods and schemes for laying underfloor heating pipes
There are several practical ways to fix underfloor heating pipes on a prepared surface:
The use of special profiles with pipe mounting sockets, which are attached to the floor surface with dowels. Such profiles make it possible to easily and evenly lay the pipe.
Fastening pipes on mats with bosses (when using a specialized thermal insulation material for the floor).
Do-it-yourself water-heated floors using heat-insulating mats.
Fastening the pipe to the reinforcing mesh with plastic ties. In this case, the screed loop should be left free, taking into account possible thermal deformations of the pipe during heating.
Fixing the pipe to the reinforcing mesh with plastic ties
This is how the finished mounted contours of the water floor look like with various types of pipe fastening:
The pipe is usually laid in increments of 100 to 300 mm. The principle is simple: the smaller the step, the more power! But with a "small" step, the total length of the underfloor heating circuit increases, which increases the hydraulic resistance. In addition to the length of the pipe, the hydraulic resistance is affected by each of its turns.
Loops longer than 100 m must be divided into several and a collector system installed. The contours must be made approximately the same (in length and number of turns) in order to equalize their hydraulic resistance.
Attention! One SOLID piece of pipe is used for each circuit. It is UNACCEPTABLE to use joints, couplings in the floor screed! Therefore, it is necessary to calculate the required length of the pipe before purchasing it or to mount the pipe on the floor from a solid bay (in the case of purchasing one for large-scale work).
The calculation of the contour for each room is performed separately. One underfloor heating circuit cannot be used to heat two adjacent rooms, especially at different temperature conditions in them. For example, you can not lay one contour of a warm floor in the living room and loggia. In fact, all the heat will be spent on heating the loggia, and the living room will not warm up well, especially if water enters its circuit after passing through the loggia circuit.
Underfloor heating, water installation of which is made without observing elementary practical recommendations, instead of heat in the house, can bring problems.
For a loggia, attic, veranda, hallway, it is necessary to calculate and lay your own circuit connected to the collector system.
The pipe enters the laying site, usually in the form of a coil. Therefore ... You can not pull the pipe out of the bay (and this is so easy to do) - it must be unwound gradually, laying and fixing it on the floor.
Pipe bend radius is critical! It should not be less than (for polyethylene pipes) five diameters. With a critical bend in the pipe, a whitish stripe may form at the bend, that is, it has formed a hall. It is not recommended to lay a pipe with a crease in a screed due to possible damage during the further operation at high temperatures and pressure.
When laying pipes through walls (when connected to a collector), they must be “dressed” in polyethylene foam insulation. And to connect to the manifold itself for polyethylene pipes, either a compression fitting or a Eurocone is used.
For laying pipes on a water-heated floor, the scheme may be different. Several of them can be distinguished:
- spiral;
- snake (loops);
- double helix.
The choice of laying scheme is determined by the individual parameters of the room and the functional purpose of its various zones.
For example, laying a warm water floor is done in such a way that first the hot coolant enters the cold zone of the room (near windows, balconies, external walls), and then warms up the rest of the room. The "snake" scheme has such functionality. Optimal uniform heating of a well-shaped room can be easily achieved by arranging the pipe in the form of a "spiral".
Filling the underfloor heating screed and installing the final floor covering
After completing the installation of underfloor heating pipes, it is MANDATORY necessary to carry out a high pressure test. To do this, the system is pressure tested with a pressure of at least 5-6 atm for 24 hours.
After a visual inspection of the pipes for leaks, swelling or expansion, a concrete screed is poured, which is carried out under the presence of a working pressure of the coolant in the pipes of the system.
It is CONTRAINDICATED for the latter to turn on the heating system for heating for “fast drying of the concrete screed”.
What else should you pay attention to:
- When pouring a concrete screed under a fine ceramic tile, its thickness should be 30-50 mm, and the distance (step) of the pipes should be 100-150 mm. This will eliminate the possibility of the "thermal zebra" effect.
- A screed for laminate, linoleum can be made thinner, but in this case it is desirable to use another reinforcing mesh laid under the screed over the pipes of the heating circuit.
Attention! In the case of using underfloor heating, do not lay a layer of heat insulator under the laminate! Pass the warmth to your feet.
Installation of a fine floor covering can be carried out after a period of 28 days from the date of pouring! Take your time! Let the screed "calm down".
- In the case of organizing underfloor heating on old wooden floors, you can use this method of laying pipes.
System start
The system is started with the onset of cold weather. During the initial start-up, the floor heating time can be quite long. This is determined by the inertness of the floor heat-insulating "pie". But in the future, this inertia will play a positive role. For example, in the event of an emergency shutdown of the boiler, the floors will remain warm for quite a long time.
Let your home be provided with comfort and coziness by warm water floors made by your own hands.
