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According to a recent housing study by Interhyp , the majority of German tenants are enthusiastic about owning their own property. For 72% of respondents, buying a house or apartment is one of their most ardent wishes. In order to feel really comfortable, renovation or even refurbishment measures are often necessary. Pleasant warmth, low noise levels and an individual design are particularly important to turn a house into a home. Find out in today's article how floating screed can contribute to the feel-good atmosphere of your home.

What is screed?

Screed is an insulating layer between the raw floor and the floor covering. This intermediate layer can be laid in different ways, distinguishing between three types:

• Composite screed
• Floating screed

The installation of screed is very important – not only for a flawless interior finish, but also for the prevailing atmosphere. The intermediate layer can have a lasting effect on the indoor climate, as well as the durability of your floors.

Difference: floating screed vs. conventional composite screed

The type of screed chosen by the owner and the craftsmen depends largely on the use. Conventional composite screed, for example, is relatively easy to install, but less suitable for wet rooms. Composite screed is used almost exclusively for the production of industrial floors in the commercial sector , as it can withstand greater loads. On the other hand, floating screed is suitable for almost all rooms and uses. This can be installed in wet rooms as well as in living rooms and has better sound and thermal insulation.

The big difference between composite screed and floating screed is that the former is processed directly on the raw floor . It does not require any intermediate layers and only 25 mm is sufficient for the construction of the screed. Floating screed has no contact surface with the floor or walls and is placed on top of an insulating layer. This also sheaths the walls and, if necessary, pipes, which explains the name.

Floating screed: advantages and disadvantages

Due to this special construction method, on an insulating layer and without direct contact with the floor or walls, floating screed has a number of advantages:

• Due to the additional insulation layer, the floor is warmer, which has a positive effect on the indoor climate and saves heating costs.
• The edge insulation strips previously applied to the walls provide improved sound insulation. This separating layer eliminates noise (e.g. steps) do not transmit over the walls to adjoining rooms.
• Floating screed is particularly robust and, due to its structure, is suitable for all living areas, as well as for the kitchen and bathroom.

Structure of floating screed

What exactly the structure of floating screed looks like depends on whether you want to install underfloor heating. In the following, we will discuss both variants so that you can get a better overview.

The construction of floating screed without underfloor heating

Installing screed without underfloor heating is relatively quick, but this mainly depends on whether wet or dry screed is used. The construction of floating screed without underfloor heating is carried out in the following steps:

1. First of all, the floor slab is laid.
2. This is followed by a first separating layer.
3. Next, an insulating layer is laid.
4. This is followed by another separating layer.
5. The screed is laid on top of the second separating layer.
6. In the last step, we lay the desired floor covering.

In the case of a "floating" installation, the same layers are laid on the walls as on the floor slab – a separating layer, an insulating layer and a second separating layer. This wall insulation strip is essential and makes the heat- and sound-insulating properties of floating screed possible in the first place.

The construction of floating screed with underfloor heating

Laying floating screed with the simultaneous installation of underfloor heating involves all the steps listed above. In addition, the heating pipes are incorporated into the screed. The construction of floating screed with underfloor heating is therefore carried out as follows:

1. First of all, the floor slab is laid.
2. This is followed by a first separating layer.
3. Next, an insulating layer is laid.
4. This is followed by another separating layer.
5. The screed is laid on top of the second separating layer.
6. The heating pipes are laid directly through the screed layer.
7. In the last step, we lay the desired floor covering.

In this way of working, it is important to cover the heating pipes with suitable insulating material, as floating screed must not come into contact with other components.

Area of application: Floating screed can be laid here

Floating screed can be installed almost anywhere – it is equally suitable for public buildings or private living spaces . Popular rooms include:

• Living rooms: living room, bedroom, children's room
• Wet rooms: bathrooms, kitchens
• Other rooms: hobby room, office, cellar, sauna

Since floating screed has no contact with the floor, walls and other components, it is not under tension. It can expand with temperature fluctuations and there are no cracks, as would be the case with composite screed.

Different types of floating screed

In general, a distinction is made between dry screed and wet screed . While the dry version is offered as a slab or bulk and is ideal for compensating for unevenness, wet screed has an earth-moist consistency.

There are six different types:

• Calcium sulphate self-levelling screed
• Calcium sulphate screed
• Cement screed
• Synthetic resin screed
• Magnesia screed
• Mastic asphalt screed

Calcium sulphate self-levelling screed and calcium sulphate screed are grouped together under the name anhydrite screed and are actually the same. The only difference is the location of the mix. The flowing screed is delivered to the construction site already mixed, while the calcium sulphate screed has to be mixed on site. In any case, the anhydrite screed, which is based on calcium sulphate, is ideal for use in residential buildings and, like the cement screed, is also popular among do-it-yourselfers.

If you decide to install underfloor heating, mastic asphalt screed is usually the obvious choice. This is mixed without any water and has an individual expansion.

Synthetic resin screed is a comparatively expensive variant that is more likely to be made at the request of the landlord. This special screed can be processed relatively thinly, has a short drying time and is based on synthetic resins.

While the four (actually five) types are mainly used in the private sector, magnesia screed is not recommended for private rooms. The screed is well suited for large areas and does not tolerate moisture – use outdoors or in living rooms is therefore problematic.

Screed thickness depending on the type

The thickness of the screed is usually at least 25 mm and depends on the type of screed and future use. Below you will find a clear table with approximate values of the different types of floating screed.

Screed Type	Thickness
Calcium sulphate self-levelling screed	approx. 35 mm
Calcium sulphate screed	approx. 35 mm – 45 mm
Cement screed	approx. 40 mm – 45 mm
Synthetic resin screed	approx. 30 mm – 35 mm
Magnesia screed	approx. 35 mm – 45 mm
Mastic asphalt screed	min. 25 mm

Caution: The thickness varies not only between types, but also depending on the product. For this reason, you must always pay attention to the manufacturer's instructions.

Conclusion: Floating screed is perfect for all living areas

Floating screed is very popular, especially in private living areas. It has excellent impact sound-absorbing, sound- and heat-insulating properties and is suitable for both residential and wet areas. In general, the comparatively inexpensive calcium sulphate-based variant is usually used. However, if you want to have underfloor heating installed or prefer a faster drying time, you can easily switch to other floating screeds.

FAQ: A brief summary of the most important questions about floating screed

What is floating screed?

Floating screed is a special type of installation in which the screed has no contact with other components and thus has a sound- and heat-insulating effect. This type of installation can be used in both residential and commercial areas and is very popular due to its robustness and efficiency.

Is floating screed highly resilient?

Due to the special installation, no tensions arise even in the event of temperature changes, which protects the floating screed from cracks and other damage. For this reason, the screed is very resilient and is used in the private and commercial sector. By the way, floating screed does not necessarily have to be replaced, even if it is damaged – often a repair of the screed is sufficient.

Is floating screed suitable for a wooden beam ceiling?

In general, floating screed can also be used for a wooden beam ceiling. However, in this case, you should resort to dry screed, as it is lighter and easier to install.

Can floating screed be installed on underfloor heating?

Floating screed can be laid on top of underfloor heating, or rather, underfloor heating is incorporated directly into the screed. However, it is important that there is no direct contact between the screed and the components. For this reason, all pipes are insulated with special insulating material before installation.

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