According to our architect, we only have to do horizontal floor slab waterproofing in the house.
We have already done this in the house on the first floor.
However, I'm wondering if we shouldn't also do it on the immediately adjacent garage?
In the garage, we will get about 18 cm of screed with a 10 cm slope.
What is the advantage/disadvantage of a welded membrane in the garage and how have you implemented this in your homes?
The garage is not a dwelling house!
In this respect, sealing inside the floor structure is not required.
An 18 cm thick screed? How is that supposed to work? With a cement screed thickness of 10 cm it is already difficult to sufficiently seal the bottom screed cover. No more than 10 cm will work. No screed layer will do it that way.
The other question is whether it should be a bonding screed or a screed on a separating layer.
A bonded screed usually requires 30 to 50 mm.
An 18 cm screed will crack like a loaf of bread when it dries, so it will be a joy.
A 35mm cement screed, no waterproofing, no intermediate film, no slope.
But instead requires sufficient surface protection in the form of a thick enough coat of concrete paint. Sanding must be done in advance, otherwise you can do without this step.