ᐅ Wall Construction of a Prefabricated House – What Really Defines Good Quality?

Hello everyone,

Prefabricated timber frame house manufacturers all have slightly different wall constructions. Each manufacturer, of course, promotes their building method and wall system as the best on the market. They all claim to offer the top product. However, almost none provide solid evidence to back up their claims.

I would really like to see some concrete proof or test results. I'm curious if there are any reliable tests regarding construction methods and quality.

What I have found are the recurring tests from Focus Money and similar sources. But these don’t provide information about the construction, materials used, or quality.

Are you aware of anything like this?

Thank you very much.

Best regards,
Steffen

I am not familiar with proper tests either. However, in my layman’s opinion, there is a clear trend away from using membranes inside the wall and avoiding mineral oil-based materials on the exterior. Although some manufacturers still attach expanded polystyrene (EPS) to the outside wall, more are moving away from this and using vapor-permeable wood fiber insulation instead. I built my house this way as well, but with a local carpentry company. Instead of a membrane, the OSB board is sealed airtight, which then functions as a vapor retarder. Due to the vapor permeability, the wall structure is more tolerant to errors. Wood fiber insulation was blown in between the studs. However, this type of wall construction is not entirely ecological, contrary to some claims. Having an installation cavity on the interior definitely makes sense because, in that case, you either do not have to or only rarely have to penetrate the airtight layer.

In any case, I would recommend using double drywall on the interior wall construction.
In my case, there is only a single layer of drywall, and you can definitely notice that when it comes to sound.

Not only double-layered drywall but also OSB underneath, so you can simply drive a Spax screw into the wall and everything will hold securely.

Schwörerhaus uses almost no expanded polystyrene (EPS) foam in their walls anymore.

In my case, only a single layer of 12.5mm (0.5 inch) gypsum fiberboard was installed. OSB boards were added under the gypsum fiberboard only in specific areas (kitchen wall cabinets, TV wall, shower enclosure, mirror cabinet, etc.). I don’t think double layering is necessary everywhere. It’s more common with drywall boards. Of course, it’s better, but also involves more effort and cost.

tomtom79 schrieb:
Not just double-layer drywall but with OSB underneath, so you can easily screw into the wall with a Spax screw and it will hold everything securely.

Exactly!