New ceiling lighting - pitched

[catlad]

He is rebuilding his roof he has the opportunity to put the rafter were he likes.

 

[Iggifer]

Unless it's a brick walled conservatory, which is unlikely with a polycarb roof, he is limited by the height of said conservatory

 

[Doggit]

You should actually be using 42.5mm insulated plasterboard on top of the 100 celotex to conform to current building regs. As Leds will not generate any heat worth speaking of, you don't need to worry too much about heat build up in the downlighter cavity, so if you have a chat with your local electrical merchant, and see how stubby a downlighter they can supply you, you wouldn't be going though the complete insulation. At the end of the day, whilst the downlighters are unboubtably compromising the integrity of the ceiling, unless you're putting in masses of them, I'm not sure if it's enough to worry about.

 

[RF Lighting]

The best solution that I've found for this situation, which is becoming quite a regular thing is these surface fittings.

They allow you to have reasonably discreet lights on a sloped ceiling pointing straight down without compromising the insulation at all. They also allow you to use LED lamps such as 7W megamans.

http://screwfix.com/pr-gallery.htm?id=13529#imggal1

Not sure if that link works. If not search on Screwfix for part number 13529

 

[Simon35]

Or you put the ceiling joist at the same height and have the same headroom.

Put the ceiling joists at the same height as what?

Whether you have a cold or warm room, he can put the ceiling joists in at the same height and finish up with the same head height.

 

[ban-all-sheds]

Unless it's a brick walled conservatory, which is unlikely with a polycarb roof, he is limited by the height of said conservatory

I would have thought that as it is a conservatory he is also limited by the fact that is has to have a glazed roof, otherwise it isn't a conservatory.

 

[Iggifer]

Unless it's a brick walled conservatory, which is unlikely with a polycarb roof, he is limited by the height of said conservatory

I would have thought that as it is a conservatory he is also limited by the fact that is has to have a glazed roof, otherwise it isn't a conservatory.

Well I guess it's not going to a conservatory any more! Just a single story extension with lots of windows!

 

[ban-all-sheds]

Those windows may well not allow the requirements for the u-value of an extension to be met.

 

[ban-all-sheds]

1. Those windows may prevent the extension meeting the overall required thermal performance.
   
   
2. Converting a conservatory to an extension might have planning permission implications.
   
   
3. The ability of the walls to take the load of a proper roof should be checked.

 

[catlad]

Simon 35 That term banging your head against a brick wall !!!!!!!!
Doggit insulated plasterboard and warm roof construction don't go together.