Insulate the attic with insulation elements

Hello! and thank you very much for your interest in my problem :)

first of all: I am not an expert.

I want to insulate my screed floor (160 sqm) with insulation elements on a (basically) level concrete floor. The elements can be laid floating.

-Do I need a vapor barrier? One supplier (Anderhalden AG in OW) advised me against it, others recommend it.

-One room of 25 sqm is about 2 cm higher than the rest of the room. How do I proceed here? Do I have to apply an additional screed layer to the rest of the room, or is there some kind of bridging?

-Are there any serious points that I have forgotten?

Thank you very much for your tips!

Greetings from Phil

Hello Phil,

Whether you need to use a vapor barrier or not should be asked from the manufacturer of the insulation elements; for example, new cement screed can release moisture (as vapor) for quite a long time. Although the amounts are small, they could still lead to defects. If you want an evenly level floor, you have to apply a fill layer; there are fills with a minimum fill height, which should be considered when choosing the product. Bituminized wood fiber and granulate fills can be applied, for example, from a fill height of 1 cm.

All technical matters to be observed during installation can be found in the technical data sheet of the product and in the manufacturer's processing guidelines - you must read and follow them carefully; the data sheets can usually be found on the manufacturer's website.

For my roof insulation, I used thermal hemp. Since I also have two windows there, I bought roller shutters that also insulate well....

Hello Arweng, The question was about the insulation of a floor; Thermohemp is not suitable for this because it is not sufficiently compressive resistant.