Is it sensible to dry screed with underfloor heating faster?

Hello,

I received the screed in the house on 03.04. The original plan was to activate the underfloor heating after one week, using the screed drying program. Since we are now running behind schedule, the builder wants to save time and turn the underfloor heating up fully after one week (whatever the case may be). The site manager says that this could cause cracks in the screed. If that happens, they would seal the cracks with a special resin.

My question now is whether this is a good idea and if any problems might arise afterwards. On the one hand, of course, I want everything to be done properly. On the other hand, it would be advantageous to recover some of the lost time since the rental apartment has already been terminated.

What do you think about this?

Expert Guide: Heating Protocols According to Types of Screed
What is a heating protocol? How is it used during the heating of screed? Where can it be obtained and who carries out the protocol? What is recorded in detail within it?

The heating protocol is a regulation for controlled functioning, readiness for covering, and cooling down of screed with underfloor heating. It serves as documentation of the work steps, has the character of a certificate, and must be provided to the contractor no later than before the installation of the surface covering.

Regulations for Laying Screed with Underfloor Heating
An underfloor heating system is practically the heating layer in the systematically and thus layered constructed floor. The floor heated in this way over its surface must be planned so that all components, starting from the substrate through the insulation, the underfloor heating itself up to the surface covering, are optimally coordinated to form a permanently functional unit that meets all energy requirements.

The materials and techniques used for processing and installation must comply with both the current state of the art, as well as the relevant data sheet and the installation guidelines of the corresponding system providers and manufacturers. The following DIN standards are of significance regarding the professional heating of screed:

[*]DIN 18353, Edition 2016-09: VOB Construction Contract Procedures - Part C: General Technical Contract Conditions for Construction Works (ATV) - Screed Works
[*]DIN 18560-2, Edition 2009-09: Screeds in Construction - Part 2: Screeds and Heated Screeds on Insulation Layers (floating screeds)
[*]DIN 18365:2015-08: VOB Construction Contract Procedures - Part C: General Technical Contract Conditions for Construction Works (ATV) - Floor Covering Works
[*]DIN EN 1264-4:2009-11: Floor Heating and Cooling Systems with Water Flow - Part 4: Installation; German Version EN 1264-4:2009

For underfloor heating, a heating protocol must be kept, which must be presented to the floor covering installer according to VOB DIN 18365 Floor Covering Works. Information on the coordination of those involved in planning and execution can be found in "Interface Coordination for Heated Floor Construction" of the Federal Association of Surface Heating Systems e.V. (BVF).


Schematic representation of the documented flow temperature profile in an underfloor heating system during the heating-up, readiness for covering, and cooling-down of screed. (Graphic: Energie-Experten.org)
Expert Knowledge: When installing underfloor heating, instead of conventional screed, so-called heated screed is used. This differs, among other things, in the guideline values for residual moisture from conventional screed, which is used without underfloor heating.

Process of Screed Drying According to Protocol
For commissioning an underfloor heating system beneath the screed, there are regulations that precisely define the process. Adherence to the prescribed procedures is of utmost importance because only then does the heated screed dry professionally, without damage and can be covered with floor coverings. In this context, one also speaks of the readiness for covering of the screed, which is achieved by the prescribed heating process.

After applying the screed and an appropriate waiting time as well as the functional test, i.e., the leak test of the underfloor heating pipes, the readiness for covering of the screed must be ensured by controlled heating of the construction according to the so-called heating protocol (also called action protocol) for the preparation and installation of elastic, textile coverings as well as parquet and wooden floors.[/B]

Hi,

yes, no question that this is better. I have also meanwhile spoken with a building surveyor. I will definitely insist that the screed drying program is used.