Minimum thickness screed

by Staenis | 14/03/2021

What is the minimum thickness of screed?

Screed, subfloor, screed, etc. There are many names for the cement layer that forms the substrate for your actual floor covering. Under the screed is often floor insulation, with the electrical and sanitary pipes underneath. But how thick should your screed be at least? Discover the ideal screed thickness for each type of screed.

What determines the ideal thickness of a screed?

If you are going to lay a floor, you should always provide a screed or floating floor. After all, this cement layer forms the even and solid basis for your floor covering. Do you also wonder how thick the screed should be at least? The ideal thickness of your screed depends on several factors: the type of screed, the composition of the mortar and the presence of underfloor heating. We go over the main types of screed and the requirements for their thickness. A floor expert will be happy to advise you on the suitable screed thickness and floor structure for your project. Discover your ideal floor structure here and get useful tips.

Screed thickness with adhesive screed

A adhesive screed is a screed that is laid directly on the supporting floor. A primer or bonding layer is first applied to this supporting floor in order to facilitate adhesion. If the cement-bound screed is placed directly on the supporting floor, the minimum thickness of your screed is about 30 to 50 mm. If you go for an anhydrite screed, then you use a minimum screed thickness of 40 mm. Haven't arranged a screeder to do your job yet? Discover how you can easily lay your own screed using a handy DIY system.

The thickness of the screed with non-adhesive screed

A non-adhesive screed is applied to a water-resistant membrane or vapour barrier, and therefore does not come directly on your supporting floor. An ordinary cement-bonded screed requires additional reinforcement with reinforcement meshes or the Staenis grid. Alternatively, you can opt for a fibre-reinforced screed (fibre compound) or anhydrite screed. In this case, you go for a minimum thickness of 50 mm for cement-bound screed. The minimum thickness for anhydrite screed is 40 mm.

The thickness of the screed with floating screed

Floating screed is a layer of screed that is physically separated from the underlying load-bearing floor and walls. An insulation layer is applied between the screed and the supporting floor and walls. This insulation layer can be installed for thermally insulating or acoustically insulating reasons. This often involves sound insulation to reduce noise nuisance in apartment buildings. Because the screed is separate from the supporting floor, additional reinforcement is always required. The minimum thickness is 50 mm for cement-based screed and 45 mm for anhydrite screed. Do you want to get started yourself and save a lot of money? With this innovative DIY system you can easily install your reinforced floating screed yourself, even if you have no experience.

Thickness of the screed layer in anhydrite screed

Anhydrite screed is a screed based on anhydrite, a recycled plaster. The base is therefore not cement as with a traditional screed. Anhydrite screed is no less than three times as strong as cement-based screed. Due to its strength, the minimum thickness of anhydrite screed is slightly lower. For an adhering anhydrite screed you can start from a thin screed with a minimum thickness of 30 mm. For a non-adhesive anhydrite floor, the minimum thickness is 40 mm. And for a floating anhydrite screed, the minimum thickness is 45 mm.

Screed thickness with underfloor heating

The presence of underfloor heating also has an influence on the screed thickness. With a wet system, the pipes from the underfloor heating pass into the (wet) screed. The thickness of the screed with a wet system is 8 centimetres on average. The thicker screed layer is necessary to be able to cover the pipes, but also to be able to better spread the heat over the floor. That is why you must provide at least 45 mm of screed above the pipes. In a semi-dry system, on the other hand, the screed does not contain any pipes. In that case, a screed thickness of about 60 mm for cement-based screed and a thin screed layer of about 40 mm for anhydrite screed will suffice. Would you like to know more about the combo screed and underfloor heating? Then be sure to read the article 'What is the minimum thickness of screed on underfloor heating?'.

Budget tip: lay your screed yourself and save

Want to save on the costs of your project? As a DIY-er, you can save money by building yourself. Laying your screed yourself nowadays is also possible, even if you have no experience, thanks to the 'screed grid' from Staenis. This grid ensures a flat, crack-free screed. You save money, you don't have to wait for your screed installer and so your project goes more quickly. How thick should your screed be if you use the Staenis grid? With a classic sand-cement screed without underfloor heating, you maintain a minimum thickness of 60 mm. With a classic sand-cement screed with underfloor heating or in a garage, you use an average thickness of 80 mm. Learn how to install your own floor construction here.

Do you want to save money by laying your screed yourself? With the innovative Staenis self-build system you can install your floor structure quickly and flat, without the risk of cracks. Use the floor construction tool and get more information about your ideal floor construction. You can easily order your supplies online via this webshop.