Steel in attic conversion where should it go?

bobbyg

Hi, I am in the middle of getting an attic conversion with dormer window and Dutch hip (previously a hip roof, think that's what it is called). Anyhow the engineer specified that the steel rest over the joists so it looks like we are losing a good 6-7 inches in height. Is there a reason for this? it should be a decent size room but seems a shame to be losing the height.

NickNickleby

we had this done.

The steel girders are set into the walls at either end of the attic. Then special brackets were hung off the girders to support new joists and the floor laid on those. So , as far as I can tell, the new floor sits level with, or slightly below the top of the girders.

Given that I went through planning process, architects etc, I'd hope this is kosher:eek:.

NickNickleby

NickNickleby wrote: »

we had this done.

The steel girders are set into the walls at either end of the attic. Then special brackets were hung off the girders to support new joists and the floor laid on those. So , as far as I can tell, the new floor sits level with, or slightly below the top of the girders.

Given that I went through planning process, architects etc, I'd hope this is kosher:eek:.

Having re-read this, I can see it's confusing.
The steel girders traverse the attic from gable to gable. They sit almost on top of the existing bedroom ceiling joists, possibly a cm or so. Rather than place new joists on top of the girders - thereby losing significant headroom - the aforementioned brackets were used.

Hope that's clearer.

bobbyg

NickNickleby wrote: »

Having re-read this, I can see it's confusing.
The steel girders traverse the attic from gable to gable. They sit almost on top of the existing bedroom ceiling joists, possibly a cm or so. Rather than place new joists on top of the girders - thereby losing significant headroom - the aforementioned brackets were used.

Hope that's clearer.

Yes that's exactly the way mine is now I don't think I was clear in my initial post. Did you lose much height? It seems a shame but I'm sure it must be essential

NickNickleby

Indeed it was a significant loss, given that the original attic (not hipped or whatever you call it) already only had 6ft headroom at the centre. I think it cost us 3 inches or so.

still, as per planning permission, its only used for storage, and one can bump one's head while in there. Seems a bit of a waste, as smaller people under 4 ft tall would love it as a bedroom.

Gumbo

bobbyg wrote: »

Hi, I am in the middle of getting an attic conversion with dormer window and Dutch hip (previously a hip roof, think that's what it is called). Anyhow the engineer specified that the steel rest over the joists so it looks like we are losing a good 6-7 inches in height. Is there a reason for this? it should be a decent size room but seems a shame to be losing the height.

This steel will carry the new floor. It may also be taking the dwarf walls.
When I’m doing planning for attics I always tell the owner, expect to loose height.

If you don’t it’s a bonus.

Gumbo

bobbyg wrote: »

Yes that's exactly the way mine is now I don't think I was clear in my initial post. Did you lose much height? It seems a shame but I'm sure it must be essential

It’s essential so you don’t put any additional loading onto what are possibly 100mm joists.

Also the volume is required to achieve a 30 minute modified fire resistant floor as per Part B Fire Safety Regulations.