One reason we don't do timber construction in the UK is that we used all of our trees to build ships, and then had to ransack North America to build more. Then we did what we do every night: take over the world.

Also, we have pretty good clay for bricks.

Yes, our village used to be famous for it's bricks.

Looks like I was way out on wall construction

Yes, very. 95% of all new houses are still the standard buildings, which are insulated, but only to the point where they meet the standards set by law. Only very few people go through the trouble of investing more into their houses to make them consume less energy. The only thing people do is install stuff that is subsidised by the government (like PV panels), but hardly anything else.
The places to be for true passive houses are Germany and Austria. The standards set there are a lot stricter than over here. They actually go for something that is beyond passive houses: the zero-emission house, which is completely self-sustained.

This was an area where the architect and builder spent a lot of time deciding how to detail to avoid cold bridging and leakage. I forgot to say our windows are wood clad externally with Aluminium

Just like here then

Whoa! I say! 240mm of cellulose fiber and another extra 50mm after the OSB. No wonder it still feels relatively warm now. This indeed much closer meets the passive haus standard! Good for you!

This is a very good setup! The only thing I would do different is I would fill the void below the floor with polyurethane. It's very important to have a well insulated floor, more important even than well insulated walls.

But this is nit picking. The rest of the setup is awesome!


Good choice, this avoids cold bridges entirely. But I wanted aluminium windows per sé because of the zero maintenance.

The extra 50 was never installed, the airtightness barriers were all the other side of that so the architect/engineer decided they didn't need it

We weren't allowed to, building regulations demanded a void and ventilation to the underside of the foundation to avoid radon buildup, even though we don't have any such risk here.

Yeah, I looked at a Belgian supplier of Aluminium systems with really low U values but the house is so timber rich that it just felt wrong to use non timber windows.

Radon buildup??? With simple concrete?? Never heard that one before. And here, all new houses have insulation underneath the concrete floor plate as well as on top. So I guess all new houses here are all Radon accidents waiting to happen?

Indeed, with the materials used I don't see how this could ever happen. These type of materials don't need ventilation. But hey building regulations, I know... don't get me started on those!

It's an issue in some parts of the UK which sit on granite, radon seeps out of the ground so regs demand a ventilated substructure. We sit on solid clay but still had to follow the reg, apparently some places will let you build without a void but our officer wasn't interested in listening.

Our ground here is clay as well. I wonder if that radon issue could be solved with a thick concrete floor plate. Probably not, because otherwise I'm sure they'd do it. (or not, because they're staring blindly at their building regulations...)

I think the or not scenario is more likely

This is the roof/wall junction, on the roof we have 300 + 150 insulation

Now, this is VERY nice! I wished I had done that as well, but my roof only offered space for 200mm of insulation. Still, the attic is not finished yet and I might lengthen the battens so I can add another 100mm or so, but I'm not sure yet.

Love it, insanely jealous!

Radon appears to be an issue in PHs:

http://www.aecb.net/forum/index.php/topic,3745.0.html