Which screed is best for a warm water floor?

Filling screeds is one of the main moments of installing a warm floor. It is on the quality of this rather complex work that the strength of the entire structure depends, as well as its appearance. Most often, this stage is entrusted to professionals, but it can be completed independently. Which screed is best for a warm water floor, you will learn from our article.

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To keep the floor warm

Installation of underfloor heating is a laborious and demanding task. Everything is important here:

• high-quality and accurately calculated circuit;
• the material of which the pipes are made;
• flooring material;
• strict adherence to technology;
• the right choice of screed;
• compliance with all installation features.

Important! It is necessary to correctly calculate the scheme and lay the pipes well before the screed is completed. If it is already installed, free access to the heating system will no longer be. Suddenly discovered error will lead to the fact that you have to re-perform a huge amount of work.

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Types of Screeds

Do-it-yourself screed for a warm water floor can be one of the following types:

• associated with the base;
• floating;
• Poured onto the separation layer.

Related

Such a screed is rigidly attached to a concrete base. There are no separation layers. In order for the pouring to hold firmly, the floor must be carefully prepared:

• remove dust;
• primer.

The main plus of the coupled coupler is that it can withstand very large mechanical loads. But there is a very significant minus - when dried, the construction sometimes changes size, and very unevenly. Accordingly, cracks form.

Important! This option is suitable for not very high rooms. The minimum layer thickness is 2.5 cm.

Floating

This is a separate independent construction, not connected in any way with the base. Such a screed is necessarily applied to the waterproofing layer. For the manufacture of heat-insulating and soundproof materials. It could be:

• mineral wool;
• wood stove;
• cork sheet;
• polystyrene foam.

Important! Floating screed is thicker than bound - the layer can not be less than 5 cm.

On the separation layer

This design is done on a concrete base. In this quality you can use:

• reinforced concrete slab;
• cement roughing.

The base is coated with a waterproofing film with a thickness of 0.2 mm or more. Stripes should overlap. They are glued with special tape, and the free edges adjacent to the walls are wrapped up.

Important! The pouring thickness may not be less than 3 cm.

Now you should already be a little more clear which screed is better for a warm water floor. But that's not all.

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About Materials

Screeds differ in the type of materials. They are:

• concrete;
• cement-sand;
• gypsum;
• expanded clay;
• magnesia;
• foam concrete.

For self-production of underfloor heating, concrete and sand-cement fillings are most often used. They are suitable for all types of rooms, including those where there is always high humidity. But it is worth learning a little about other materials to understand which screed is best for a warm water floor.

Gypsum

Plaster mixes for underfloor heating appeared in construction stores relatively recently. Gypsum gives good noise protection and provides reliable thermal insulation. It has a relatively low density.This is a fine-grained material that penetrates perfectly into any cracks. It is very important that the gypsum mixture does not burn.

Important! For rooms, such a screed will be very good, but for the bathroom it will not work, gypsum is deformed under the influence of moisture.

Expanded clay

This is a variant of a sand-cement mixture with a special filler. Expanded clay is added so that the screed lies better - its particles are very small in size, so even microscopic holes are easily filled.

In contrast to the usual sand-cement mixture, no preparatory work is necessary before pouring the expanded clay composition. Just sweep the floor. But this material absorbs moisture, so it is covered with PVC film.

Important! Sand-gravel is similar to expanded clay mixture - it is laid according to the same technology.

Magnesite

This is a very interesting composition, the components of which are:

• magnesite;
• mineral fillers;
• bischofite solution.

Important! This mixture is not suitable if metal parts were used during the installation of the warm floor - it causes corrosion. If it is necessary to use just such a composition, the metal elements will have to be coated with insulation.

Foam concrete

Modern material that is gaining popularity when it comes to choosing which screed is best for a warm water floor. Material is different:

• monolithic structure;
• low weight.
• good soundproofing.

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Making a sand-cement mixture

To the question of what kind of screed to do for a warm floor, many will answer - concrete or sand-cement. These are relatively cheap and quite traditional options.

You will need:

• cement grade M300 and higher.
• coarse sand;
• plasticizer (optional).

The solution should be thick enough, but at the same time, fit without effort and when smoothing, do not give lumps. The mixture is prepared as follows:

1. For 50 kg of cement, take 200 kg of sand and 1.5 liters of water.
2. Add 150 g of liquid soap.
3. Mix thoroughly to make a homogeneous mass - for this you need a construction mixer.

Important! You will also need 20x40 metal profiles.

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Concrete mix

The sand-cement mixture is made relatively simple, but it is not always suitable. Concrete is preferred in every way. You can also prepare a concrete-expanded clay mixture, which will give the screed greater strength. In addition, this option gives better sound insulation.

Instruments

All the necessary tools to fill the screed, you probably have. You need:

• shovel;
• Master OK;
• building rule.

Preliminary work

Screed - this is the final stage of installation of a warm floor. Before filling, the surface must be prepared. Fill the pipes - this is necessary to avoid their deformation. Water temperature should not be higher than 25ºС.

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Pouring

Most often, the screed is made on lighthouses - small bulges. For them apply:

• gypsum;
• alabaster;
• the same concrete mortar.

It is very important to correctly calculate the height of the beacons - the water must flow in the system. In order for the concrete mortar to stay on the surface, formwork is needed, but it cannot be placed on pipes.

Important! In construction stores you can buy ready-made lighthouses.

Mount the floor

It is convenient to adhere to this procedure when installing a warm floor.

1. Prepare the base by removing dust from it.
2. Spread a plastic wrap on the stove.
3. Lay a layer of foam or mineral wool on it.
4. Spread heat-reflecting film.
5. Lay the pipes.
6. Cover them with reinforcing mesh.
7. Paste the walls with damping tape.
8. Install a wooden formwork around the room so that it does not press on the pipes.
9. Set up the lighthouses.
10. Prepare a solution.
11. Fill.
12. Lay expansion joints - grooves through the entire thickness of the layer (you can lay the slats and then get it out).
13. Level the layer and remove the bubbles - this can be done, for example, with a rake, but it is better to use a needle roller.
14. Paul will be ready in about a month, although during this period you can walk on it.

Important! During operation, periodically spray the floor with water - this will prevent the appearance of cracks.

Where to lay expansion joints?

Without such joints, the floor is easily deformed, while cracks will form anywhere. To prevent this from happening, experts recommend laying seams as follows:

1. If the room is not more than 16 square meters. m, lay seams along the walls.
2. In the large room, make additional seams.
3. Lay damping tape.

Important! Before pouring the screed, sketch the location of the pipes and do not forget to specify the exact dimensions.

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Stock footage

In principle, now you have enough information not only to decide which screed is best for a warm water floor, but also to do it yourself. In this and wish you good luck!