[cycomanic]

It's funny how every country thinks their approach to building is good and everything else has huge problems. For example Germans tend to think wooden houses will not last.

The approach taken here is similar to what people are commonly doing in Scandinavia. Most generally almost all houses are pre fabricated in factories and assembled on site. The actual blocks vary quite a bit, mostly they are large wall sections, but there are approaches using blocks like this. There is also a manufacturer that makes all sections out of plywood. With all of the approaches I have never heard of issues with leakage. In fact they tend to be much more tight then houses build on site (often meeting passive house standards).

[class3shock]

Structural Insulated Panels - SIPs (which I think is what you are talking about) have arguments in their favor as they actually benefit from many of the upsides of building things in factories vs on an individual/onsite basis. These do not seem like they'll realize any of those (since you are just prefabing a component comparable to a sheet or board as opposed to a whole wall).

SIPS absolutely do have issues with leakage, the same as any construction method. Joints, penetrations, windows, etc. can all be sources, same as in traditional framing, the difference is again that plywood / osb / glued together wood scraps are atrocious at handling moisture. I do think they are interesting though, more reading for the curious below.

https://buildingscience.com/documents/enclosures-that-work/h...

One of the benefits of SIPs for airtightness is that the layer that provides that is built in (or atleast can be) at the factory. This eliminates alot of the variables that hurt airtightness when you are building onsite (working in temps/humidity where seals don't get installed right, poor workmanship, etc.).