ᐅ Interior plaster on exterior wall not fully applied

Hello everyone,

We are currently having a house built by a general contractor (external wall structure: aerated concrete - mineral wool - brick veneer). At the moment, the plasterer is working inside (walls are being coated with lime-cement plaster). Some pipes run surface-mounted in room corners and are planned to be later covered with drywall panels (e.g., flue pipe for the gas heating system).
Currently, there is no plaster behind these pipes. The aerated concrete is visible (see photo).

So far, I have assumed that the internal plaster forms the airtight layer on the external walls. For the same reason, socket and switch boxes in the external walls were fitted with airtight membrane boxes. This seems to be counterproductive if large areas behind surface-mounted pipes lack internal plaster. In my opinion, the drywall cannot take over the function of airtightness, can it?

The issue of plastering walls behind pipes probably exists on almost every construction site. How is this usually resolved?

That’s how it is. Cladding, plaster filler applied on top, then paint or wallpaper.

Platzhirsch85 schrieb:

How is this usually handled?

Plastering before the pipe is attached to the wall, or if necessary, later manually sealing around it. This is a common source of air tightness issues.

How about using Wedi boards as cladding? They are available in angled shapes and are airtight. The cost per pipe varies between 20 and 30 euros, depending on the width. Better than drywall partition walls.

Exactly. You just use these things. The painter will simply do it quickly and efficiently.

Hello

That might look good, but it certainly won’t create an airtight layer. During the blower door test, this will become evident again.



Olli