Build Daily


August 12, 2017 18:06

Screed floor in the bathroom : wet , dry and semi-dry .fill Technology

Screed and waterproofing the floor in the bathroom
  • Species
    • Wet Dry Semi-dry
  • Substrate Preparation Prepare a mixture
  • Installation of heat and damp-proofing
  • Installing beacons
  • casting technology
  • hardening of the top layer

Any overhaul of the premises begins with the preparation for finishing floors.Many who have just recently bought an apartment, faced with the fact that the floors do not look at it in the best way.Concrete slabs are uneven, there are numerous potholes and bumps, in some places may even hang pieces fittings.That is why it is so important to perform quality screed floor in the bathroom - the application of an intermediate coating between the base and floor finishing.

The device ties in the bathroom

Screed allows:

  • hide irregularities,
  • provide additional heat and sound insulation,
  • provides the necessary degree of technological gender bias,
  • evenly distributes the load on the foundation,
  • makes it possible to hide some of the communication,
  • makes it possible to raise the floor level to the desired level.

Make a floor screed in the bathroom alone is difficult, but we will try to help you, after reading this article, you will be able to carry out this work without the involvement of professionals.But first, we want to draw your attention to the fact that the count floor height in the bathroom should be given the fact that it should be a few centimeters lower than in other areas.

If the bathroom will flood, the water is not immediately flood the apartment and other facilities you have in stock will have more time to eliminate the consequences.

Quality screed in the bathroom


The main components of the screed are water, sand, cement and gravel.If you want to align considerable differences floor height, or if the subfloor is not strong enough and it needs to be strengthened, added to the mixture expanded clay or perlite.

Screed can be:

  • wet,
  • dry,
  • semi.


wet screed is considered ideal for rooms with high humidity. When using wet styazhkisleduet remember that the thickness should be at least 3 centimeters.So if you have the ceilings in the bathroom and already low, it is not recommended.

waterproofing layer can be performed either on top of the wet screed (in this case we are talking about so-called knitted screed), and under it.In addition, under the coupler can also put an additional insulating layer.a special coating which makes floors perfectly smooth and even - If you plan to use in the bathroom decorative coating that is sensitive to the slightest changes in elevation over screed or instead is self-leveling floor.

Wet screed in the bathroom


When using dry screed in the bathroom need to be careful, because it is likely that over time this screed cracked under the influence of moisture. Therefore, in the bathroom a tie is rarely done.In addition, it will cost much more expensive than other types of ties, as increased consumption of building materials.

When the dry floor screed is laid first layer of expanded clay or gravel, then spread evenly a dry mixture, and on top of stacked sheets of moisture-resistant drywall.

Among the advantages of this type of screed is worth noting the fact that it does not require any particular labor costs, and away from the apartment is the least dirt.Furthermore, on top of the dry screed not need any additional coating stack except decorative directly.

Dry screed in the bathroom


In the manufacture of semi-ties in the lightweight aggregates are added to the solution, which reduces the load on the floors, reducing the coating weight and dry much faster, compared to the wet screed.

This tie cost more than wet, and requires special skills and use of additional equipment.So, first you will need to knead the mixture for screeds, mixing water with the required components in the correct proportions, and then, after drying, the screed must be wipe to get rid of possible irregularities and bumps.

Semi-dry screed in the bathroom

There is another qualification ties, which is based on what the layers are separated from the base screed.

  • If screed is performed once directly on the base, then we are talking about the so-called bound screed.If
  • between the screed and the base used separation layer: polyethylene film or other waterproofing material, then a tie is called separation.
  • If you need more room or noise insulation between the screed and gidrozoliruyuschim layer fit additional noise and heat insulating layer.In this case we are talking about the so-called floating screed.
Floating screed floor in the bathroom

Substrate Preparation

Before you lay any of the above types of screed, it is necessary to prepare a base.Earlier in the bathroom was already made screed, its old layer must be completely removed.Screed

- monolithic layer to be uniformly distributed over the surface. Otherwise she quickly cracked and will bring you a lot of hassle.After removing the old ties should be thoroughly sweep the floors and grout to cover all the cracks in the ground, if any.Some builders also suggest primed base before performing the tie.

then need to hold the installation and wiring of communication pipes.As we already mentioned, all communications are hidden under the screed, and the warmth and waterproofing is done already bypassing them.

extremely important step in the preparatory work is laying the waterproofing.Skilled craftsmen are advised to use the bathroom in a bitumen mastic and various roll waterproofing materials.This waterproofing will protect not only the floor, but the base of the walls, as the capture and walls to a height of 15-20 cm from the floor.

Waterproofing of the floor in the bathroom

Preparing the mix

Regardless of what kind of tie you will use, you first need to calculate average consumption of mixture per square meter, as well as to determine what thickness would tie in differentsites.


  1. To do this with the help of leveling get the lowest and the highest point of the floor.
  2. to the highest point, add a minimum height of screed, which is allowed in this room and calculate what will be the thickness of the tie at the lowest point.
  3. Find the average value and multiply it by the amount of the mixture flow in the 1st quarter.m. area.

If the height difference on the different parts of you big enough, the mixture must be purchased with a margin.For the rest, follow the instructions on the package with the mixture.

Here is an example: suppose you use to tie the cement mixture having a flow rate of 13-15 kg per 1 sq.m with a thickness of 1 cm.

If the bathroom is 15 square meters.m and the average thickness of screed - 5 cm, then you will need to multiply the average of the mixture flow rate of 14 kg / m2 * 5 cm * 15 m2.Thus, eventually all you need to about 1050 kg mixture.This 42 standard bag of 25 kg.

Such calculations can be done easily by using ready-made mixtures for floor screeds.If you plan on using cement-sand screed, then you need to start from the fact that 1 part of cement used is usually 3 parts sand.

average consumption of cement in the cement-sand screed floor of 1 cm to 1 m 2 - 5 kg, and sand - 15 kg.

Dismantling of old concrete screed
Bags with screed floor
Lightweight floor screed

If you plan to perform a cement screed, concrete is better to take a ready-made.In any case, the flow rate of the cement mixture or concrete per square meter must be checked with the seller or the manufacturer.

In some cases, builders are also added to the mixture of special additives that minimize the amount of water required for mixing.The mixture while it is still plastic and easy to apply.Plasticizers for concrete screeds are applied when laying the floor heating system in the bathroom.

Screed on underfloor heating system in the bathroom

Installation of heat and damp-proofing

proofing in the room with high humidity is always needed.There obmazochnye, plaster, cast, rolled and Sediment vlagoizoliruyuschischih variety of materials.

floor insulation is needed in homes with a cold base. As a rule, these are private homes and apartments, which are located on the ground floors of buildings.

need for heat-insulating layer is no longer the case, if you plan to install the system in the apartment of "warm floor".a layer of expanded clay can be used for thermal insulation of the floor, Styrofoam, polystyrene, cork, glass wool or mineral wool.

Hydro and thermal insulation of the floor in the bathroom

Installing beacons

to floor screed was carried out exactly as possible, establish special beacons - guides from the T-shaped profile, or wooden bars. All beacons must be placed on the same level - where will end with the height above the floor screed. Beacons can be left in a screed, and retrieve them after the screed will be performed.If you plan to leave the beacons inside covering, they definitely need to treat corrosion or repellent, so that in time they will not have rotted, and because they were not formed cracks.

Installation of beacons under the screed in the bathroom

Stages of work:

  • First, measure about 20-25 cm from the wall.There's the first beacon is located.The rest are located at a distance of about 40 cm from it.
  • In the place where the planned placement of beacons, at some distance from each other dot position a few bumps cement.They beacon will be held.
  • Place beacons across the floor space and allow the mortar to harden.Only then will proceed directly to the implementation of the screed.

casting technology

screed is recommended once in the entire area of ​​the room.

solution for water-based screed hardens within 1-1.5 hours.Therefore, it is necessary to work with a fast pace.

Fill carried stripes between established beacons.If you do not plan to leave the beacons in the fill, then in between the strip you fill through one.Once the solution dries, beacons must be removed, and the distance between the bars to fill the remaining solution.

Fill the floor cement-sand screed

Here are some tips for filling floor:

  • Fill should begin to perform from the farthest corner from the front door.
  • solution is poured a little above the level of beacons, then compacted and leveled using a special tool - the rules.Rule feature ends at the lighthouse close to the wall, and constantly moving from side to side, slowly moving forward.Excess solution is used to fill the next strip.
  • wet and semi-dry screeds need to be added to jam after pouring, the surface is perfectly flat.This can be done manually, making a circular motion tool, and with the help of a special machine for floating floors.The surface of the screed when it is necessary to moisten spray.
  • After grouting is necessary to recheck the level of how evenly distributed the tie you whether distortions anywhere.If everything smoothly, screed covered with plastic wrap for two weeks, periodically checking its condition and maintain the proper humidity level.
  • Some experts advise in the process of pouring the floor pierced mixture thin metal rod.This is done in order to avoid the formation of air voids in the screed, which can subsequently lead to cracks.
  • Complete drying screeds take up to 28 days.

Now on sale, you can find a mixture of so-called self-leveling floor.Working with them is really simple - you do not need to install beacons or sanded screed.


  1. mixture is distributed over the surface evenly, starting from the far corner of the room.
  2. After the mixture covers the surface of the floor, it must be uniformly distributed with the help of a doctor blade or spatula and special puncture needle roller to prevent occurrence of air bubbles in the solution.

Such mixtures are actually more comfortable than classic, but they will cost you significantly more.In addition, large areas of self-leveling floor is not very convenient to use - it differently, we have to distinguish between the room into several sectors and to fill them in stages.

Self-leveling floor in the bathroom

hardening of the top layer

Some floors to give additional strength using the so-called topping - a special blend, which is applied on top of the screed for its strengthening.This mixture may be a crystal or metallic filler or contain corundum.

Topping evenly distributed over the surface and rubbed directly into the screed.After it is treated with a special mixture.

Use topping for strengthening ties justified if you do not plan to cover any additional tie decorative covering.If you plan to stack the bathroom tile, laminate or other materials, there is no need to use additives.

Laying tiles on the screed