Perhaps the other point is the area given over to circulation - the bungalow will almost certainly have a worse net to gross ratio so you get "less" house

It's also more difficult to service for systems that need short runs - HWS primarily - easier to stack similar functions and service them vertically - less material cost and less energy "lost"

Regards

Barney

True - although the trade off is probably net positive

Regards

Barney

Lots of 1920's/30's semis about 5.5 - 6.5m wide, and 8+m deep. 5.6 is wide for a terrace in this neck of the woods.

That’s a good response Ed. I was basing my thoughts on the possibility that a roof could be insulated with rockwool whereas a wall may need to use a rigid insulation which is about five times the cost for the same U value. I’m not sure how to cost the building elements more accurately for now.

Posted By: Nick Parsons''This is getting to the limit of what normal sized floor joists can cope with.''

Yes, but many of the 20s and 30s semis round here have 4 x 2 (100 x 50mm) joists with the span broken by sleeper walls. No joist in these houses would be spanning the full width.

I was assuming the joists would run from the front and back walls to the "spine wall", so would be half the depth of the house. (Running them the other way don't work if the stairs are next to the party wall.) Sleeper walls don't help on the 1st floor.

Oh I agree – and the eaves are where you’d lose most heat. However, the point I was trying to illustrate with my slightly far fetched example was that the most cost effective shape depends upon the relative costs of the different building elements. For all I know walls could be >2.5 times more expensive per square meter than roofs and floors. And as others have mentioned above it also depends upon how useful the enclosed shape is. (An extreme example I’ve seen are the cubist houses in Rotterdam – which weren’t very popular until fitted with built-in furniture to make better use of the space.)

Posted By: EasyBuilderOh I agree – and the eaves are where you’d lose most heat. However, the point I was trying to illustrate with my slightly far fetched example was that the most cost effective shape depends upon the relative costs of the different building elements. For all I know walls could be >2.5 times more expensive per square meter than roofs and floors.

I can see your point in principle, but I [have to] assume that it isn't widely acknowledged in practice because the price differences aren't as extreme, or may even be reversed?