What is the thickness of the screed?


The thickness of the screed floor is determined not only by the construction method of the screed, but also by the requirements of the load-bearing capacity. Since mostly floating screeds are used in living spaces, the layer thickness of the screed layer is generally lower here because in addition the components for thermal insulation and impact sound insulation are added. If the screed is designed as a heating screed, the screed construction is usually made thicker there, but a good heat transfer from the heater to the room is usually guaranteed; In addition, mostly flow screeds are used here. At least the screed layer in Wohnräumenaber should have in any case a thickness of four centimeters. It only has to be equally strong when it comes to floating screeds.

Nominal values ​​according to DIN 18560 for the individual screed constructions

Composite screeds have according to the DIN a possible installation thickness of between 20 and 70 millimeters, tailored to the intended use in the respective utility rooms. For sliding screeds, the DIN prescribes a minimum thickness of 30 to 45 millimeters depending on the binder, whereas for floating screeds it requires a build-up of at least 40 millimeters. In addition, for a floating screed and the edge strips must be at least 8 millimeters thick. In the case of heated screeds, the required minimum thickness depends on the construction method of the underfloor heating - DIN distinguishes between heating elements installed in the screed layer, those laid in the insulating layer and heating elements in a separate screed leveling layer. Depending on the type of screed, however, a coverage height of the heating elements according to DIN must be at least 40 to 45 millimeters for heated screeds.

Pressure and bending tensile strength of the screed

A measure of the correct screed thickness in each individual case is provided by the values ​​for the compressive strength and the bending strength of the screed, which are given in N / mm². Both must be given in the description of the screed and its execution - as C and F value in the standardized screed description according to DIN. If you install your screed yourself, of course, the minimum installation thicknesses according to the DIN are decisive, if you are not sure about the required thickness of your screed, do not hesitate to simply ask a specialist.

What is the thickness of the screed?

FAQ - 💬

❓ How thick should a floor screed be?

👉 If we look at each different type, you’re going to have different floor screed thickness on the minimum and maximum depths. The maximum depth you would use a smoothing compound would generally be around out 10mm, you can add aggregates, to bulk up the screed going up to 30, 40, 50+mm.

❓ What is the maximum thickness of a monolithic screed?

👉 For concrete ground-bearing floors, a maximum 20mm monolithic screed may be acceptable as part of the required thickness.

❓ What is the minimum depth for screed bonding?

👉 Bonded Screed Minimum Depth When bonding directly to the substrate with a bonding agent or a primer the minimum is 1-2mm (feather edge) with smoothing compound Modified sand and cement screed can start at 10mm, that is for a rapid strength and fast-drying product Traditional sand and cement such as a 1:4 ratio could be bonded at 40mm

❓ How thick should a screed be for a 300mm substrate?

👉 If you have a 300mm of depth, you might want to put in 225mm of insulation, leaving 75mm of screed. Drying times for a standard screed at 300mm would astronomical, and another reason not have the screed too thick. Unbonded, with the membrane in between the substrate and the screed.


Video Board: Sand Cement Screed Thickness Minimum?