ᐅ Which type of screed do you prefer?

Created on: 22 Oct 2023 12:29
S
se_na_23
Hello,

We were originally supposed to use a calcium sulfate screed (Maxit). According to the technical data sheet, it has a thermal conductivity of about 1.83 W/mK.

The construction company now wants to use a product from Hasit instead: Hasit cement sulfate screed. According to its data sheet, it has a thermal conductivity of about 1.4 W/mK.

Our contract specifies calcium sulfate screed. Should we insist on that since it has better thermal conductivity?

Thank you.
J
Jasmin
22 Oct 2023 14:20
Hello, our independent construction supervisor at the time strongly recommended cement screed (in case of water damage). What can I say, we did experience water damage, and at least regarding the screed, we were relaxed about it. Water damage in the utility room caused by a broken heating circuit pump (?)... after three years, you just never know what will happen.
A
Allthewayup
22 Oct 2023 14:45
Jasmin schrieb:

Hello, our independent construction supervisor strongly recommended cement screed (in case of water damage). What can I say, we did experience water damage and at least regarding the screed, it was not a problem. Water damage in the utility room caused by a broken heating circuit pump (?)… after three years, you can’t really predict these things.

Yes, that is a major disadvantage of calcium sulfate screed. Such risks can never be completely ruled out but can be reduced through planning measures. On the ground floor, we have a niche for a vacuum/mopping robot with a fixed water connection and a drain. The calcium sulfate screed was omitted there and replaced with cement screed. In my opinion, calcium sulfate screed generally has no place in the utility room because the risk of damage clearly outweighs the benefits.
At the end of the day, however, water damage to calcium sulfate screed is covered by the building insurance; it’s just that the repairs tend to be more extensive.
K
KarstenausNRW
22 Oct 2023 15:08
In the end, the type of screed doesn’t really matter—at least during operation. Each option has its pros and cons:
- different required thicknesses
- different costs
- varying sensitivity to moisture
- different subsequent processing (sanding or not)
- different application methods (flowing screed or not)
- different drying times

For example, I used a traditional cement screed with aggregates. It was a) ready for parquet flooring after just a few days and b) fortunately installed so perfectly that no additional work was needed before laying the parquet.

P.S. I have never seen the application of cement sulfate screed.
se_na_2322 Oct 2023 15:14
Maxit 450
Hasit 465

are the types... I don’t care about the screed prices since it’s a fixed price.
Do I need more energy because Hasit is heavier and less heat-conductive?

Thank you
D
Daniel-Sp
22 Oct 2023 20:10
What exactly is supposed to happen with the heat in the screed? Where should it go? It can only transfer into the room.
R
RotorMotor
22 Oct 2023 20:27
Daniel-Sp schrieb:

What exactly is supposed to happen to the heat in the screed? Where should it go? It can only pass into the room.
A higher supply temperature is simply required to reach the same room temperature if the screed/floor covering conducts heat less efficiently or more slowly.
Whether this would actually be noticeable in energy consumption is difficult for me to estimate.