Convert from pitched roof with flat ceiling to vaulted

lah1308

we have a kitchen extension which was originally done in '92, the room is approx 4m X 3.5m and has a pitched roof at around 15 degrees. We are removing the plasterboard ceiling (which is flat) as it needs to be replaced along with new insulation.

It was suggested that rather than putting the flat ceiling back in, it's current height is about 2.1m...perhaps we should change it to be a vaulted ceiling. We will know more later today (and have pics) once the plasterboard is removed and the joists + rafters are exposed but it this a fairly standard job and does it require building control to get involved?

Also what tradesmen should carry out work like this? Roofer? Carpenter? General builder?

Doozergirl

It's mainly carpentry. You need to make sure that the joists aren't part of a truss construction. It's only small, so they probably aren't and the roof was constructed on site.

You'll need solid insulation between the rafters. The rafter might need to be made thicker to accommodate it. You'll need an air gap between the roof membrane and insulation.

15 degrees isn't much of a vault to have.

It probably doesn't need building regs approval as it should have had it initially. You can't make it any worse, but upgrading is fine. I would go to at least current regs standards on insulation as it's a money saving no-brainer.

teneighty

If you are removing the ceiling joists you will need something to stop the roof spreading, probably a ridge beam or other method.

Yes it requires Building Regulations Approval as it is a structural alteration and work on a thermal element.