Foundation or masonry: Horizontal AND vertical barrier layer?

Hello,

our house is to have 2 floors and no basement. Normally, I assumed that a foundation would be built (with drainage), the walls would be set on it, and thus the house would gradually take shape.

Now a friend pointed out to us that a horizontal barrier layer must be installed over the base to prevent moisture. Our builder confirmed this as well.

However, our friend said that this barrier must be folded around the outside and then also serve as a vertical barrier at the outer edge so that moisture cannot penetrate from outside.

Our builder denied this, saying that sealing the base/foundation on the outside in this way can trap water underneath the floor slab inside, which then cannot escape outward.

Now my question is: a horizontal barrier layer is a must - okay. But what about the vertical barrier? Who is right, and what is better?

I am grateful for any tip or advice, Best regards, Tim

Our builder denied this, as you seal the base/the foundation on the outside, but inside under the floor slab, water can collect which then cannot escape to the outside.
Tim

That's really funny

You need horizontal waterproofing and vertical waterproofing
What does your architect say about it?

Hello,

I have not spoken with him yet, I wanted to inform myself beforehand, because you also read two different opinions on the internet. Many say that if you don't have a basement and only build on a slab, you don't need the vertical barrier layer on the outside?!

Best regards,
Tim

Hello,
somehow you have to protect your structure at the base from moisture. The best way to do this is with a sealing provided for that purpose.

Detail planning is not included