I have just studded half of my garage out to make a room that I will use every now and then. The back wall is single skin brick, one side wall is a neighbours garage, the other side is the house wall so should be insultated and the front will be a fake wall with a door in.

My questions are what type of plasterboard should i use? I am going to use 12.5mm but do i need sound,wall,vapour or moisture boards.

I was planning on using rockwall for insulation and have room to come out 110mm. what type should i use and where best it to buy it from ?

Thanks for the help

i would go for celotex in the voids of the stud a waterproof membrane over the top of the studwork then vapour check boards over the top, this way you keep the heat in in the winter and repel it out in the summer.

Jr is spot on. For additional insulation, use more celotex (25mm) over the top of the membrane before adding the plasterboard with longer screws. This would also negate the need for vapourcheck boards.

Some people use a breather membrane rather than a waterproof one. This may be important if there is to be significant humidity and no passive ventilation.

I have already screwed the studs to the single skin wall. I forgot to use a Dpm Should I paint the wall with a damp proof etc or are you saying use 100mm celotex then vapour plasterboard.
Would that be to much ?

Bit confused first time

Given the studs are 100mm thick, then celotex + vapourcheck should be fine. I would even dispense with the vapourcheck and ensure that the celotex doesn't touch the outside wall, thus creating a cavity which moisture will struggle to cross.

nice one jozeffo reading my post again i realised my response wassnt very clear but i was ment to be takeing my fiancee to the midwifes though and was rushing .

Thanks guys for the help.

What size celotex should i use if the studs are 100m deep. What do you mean by vapour check ? Do you mean vapour board ?

If i use 100 celotex would that not touch the wall?

Thanks for the help

I would use batten on the inside of the studs where they meet the brickwork, then push 70mm kingspan onto them and board over the top.

If I used 70mm king span with a vapour plasterboard will that be ok.
Do I need to do anything else to the wall.

What plasterboard should I use for the ceiling

Thanks for the help

on the wall i would put a breathable membrane over the top then vapour check boards or as jozeffo said put anouther 25mm celotex over the top then boards.
what have you got on the ceilin at the moment is it insulated?
you can use just normal 12.5mm boards on the lid though but it might be worth insulateing. in fact scrub that i would insulate the ceilin too. you can get rolls of insulation that dnt itch you like mad you can buy this from screwfix
http://www.screwfix.com/search.do?fh_se ... &source=aw.
it might be more money but trust me i would pay more to not itch all day

The wall already is studed. What do you mean put a breathable membrane over the top. How would I do that. I am going to insulate the ceiling using similar stuff I will put 270mm up there.

fairplay mate.the membrane will be something like this
http://www.wickes.co.uk/bin/venda?ex=co ... h=membrane
the top one is your breathable and the very bottom one is the waterproof one.
to fix this i simply use a staple gun, this is the one i use
http://www.wickes.co.uk/bin/venda?ex=co ... staple+gun.

with the ceilin is it vaulted or is it a pitched roof but with a flat ceilin dropped down??? cos if its vaulted just make sure you leave 50mm void behind the celotex for an air gap, if its a flat ceilin dnt worry.
jus a thought

New build pitched garage roof

are you keeping it vaulted or putting a flat ceilin in though?
as i said before if its staying vaulted then just make sure you leave 50mm air gap and if your dropping in a flat ceilin then dnt worry bout that