I want to install an in-floor water based heating system in an apartment on a higher floor.
As such, there are 2 problems:
I cannot afford to have 2 layers of screed (because I need something lighter).
The current concrete slab suffers from level and adherence issues. There are holes, level differences between rooms of up to 6 cm, 2 rooms have a layer of bitum on them (was previously used as insulation and adhesive for the former flooring), 1 room has a slab of shiny mosaic-like screed that we couldn't remove.
This is why I thought about using perlite as the bottom layer (under the studded insulation panels).
- Is this a good solution?
- Does the studded insulation panel need to be anchored to the surface below using screws or something else?
- Will it have enough stability on the perlite layer if I level it appropriately?