Hello, I urgently need advice regarding my attic conversion. The roof itself has now been completely newly insulated with an external rafter insulation system (vapor-permeable system / vapor barrier). The house was built in 1972 (Schwörer house), timber frame construction with 140mm (5.5 inches) exterior walls.
- First of all, it concerns the internal insulation of the exterior walls. I would like to cover these, for example, with Sonorock Plus and stud framing. The question here is: should I install a vapor barrier or vapor retarder before attaching the drywall?
- For the interior walls, I plan to build a timber frame structure with OSB boards and drywall on both sides, insulated internally with, for example, Flexirock. The question here is whether I also need to install a vapor barrier or vapor retarder?
- In the bathroom area, should I install a vapor barrier?
- First of all, it concerns the internal insulation of the exterior walls. I would like to cover these, for example, with Sonorock Plus and stud framing. The question here is: should I install a vapor barrier or vapor retarder before attaching the drywall?
- For the interior walls, I plan to build a timber frame structure with OSB boards and drywall on both sides, insulated internally with, for example, Flexirock. The question here is whether I also need to install a vapor barrier or vapor retarder?
- In the bathroom area, should I install a vapor barrier?
You don’t need a vapor barrier for interior walls. Use the green drywall panels for the bathroom.
You should avoid working on the exterior walls yourself, as it’s clear you don’t know what you’re doing or need to do. You should definitely seek professional expertise, both for the planning and the execution.
You should avoid working on the exterior walls yourself, as it’s clear you don’t know what you’re doing or need to do. You should definitely seek professional expertise, both for the planning and the execution.
An architect once wrote that it is especially important to ensure that the internal insulation cannot be bypassed by air flow. Therefore, the substrate must either be completely smooth or the insulation material must be flexible. Additionally, there should be no gaps or cracks where air can enter the insulation.
For the internal insulation consisting of wooden battens and mineral wool, we have applied a vapor retarder (climate membrane) with adhesive—no staples, as these would create thousands of tiny holes. There are special cartridge adhesives for this purpose. The joints and connections, for example at the window, are sealed with specialized tape. In my opinion, this is particularly important for window connections, since achieving airtightness otherwise is nearly impossible.
Actually, this might be redundant, as we have a curtain wall façade, and any condensation moisture can naturally ventilate to the outside.
However, it is said that an OSB board cladding is itself vapor-resistant, at least if the joints are very tightly sealed.
For interior walls, a vapor barrier is not necessary because they do not usually cool down enough for condensation to occur.
For the internal insulation consisting of wooden battens and mineral wool, we have applied a vapor retarder (climate membrane) with adhesive—no staples, as these would create thousands of tiny holes. There are special cartridge adhesives for this purpose. The joints and connections, for example at the window, are sealed with specialized tape. In my opinion, this is particularly important for window connections, since achieving airtightness otherwise is nearly impossible.
Actually, this might be redundant, as we have a curtain wall façade, and any condensation moisture can naturally ventilate to the outside.
However, it is said that an OSB board cladding is itself vapor-resistant, at least if the joints are very tightly sealed.
For interior walls, a vapor barrier is not necessary because they do not usually cool down enough for condensation to occur.
Similar topics