fixing methods for celotex warm roof insulation

[mpheating]

sorry but im banging my head against a brick wall here, cant find a single video on installation methods for warm roofs, just really crap videos of it already done.

right..

I have a 5m x 3m built office 2.3 metres heigh with 100mm cavity walls
im going to install my joists..say 7 inch??
- I'm going to install osb 3 18mm boards on the top of the joists
- Then install 150mm Celotex insulation but I don't no what fixing method I require??
- Then install 9mm osb boarding on top of this, again I don't no the correct fixing method.
- Then install my firestone rubber roof covering.

Can anybody guide and help me out here please...

 

[mpheating]

come across this after hours of reading

http://www.rubber4roofs.co.uk/EPDM-Uses/EPDM-Warm-Deck-Roof-Design

do you agree?

If so would you use normal screws or can you recommend the right ones needed.

The only other thing that is annoying me is the membrane that is required? As this is going to be done from scratch do I need a membrane or is this the foil on the insulation board?

 

[mpheating]

one more thing...

Would you need to use the recommended Kingspan TR26 foil backed insulation or would Celotex Insulation Board XR4150 150 x 2400 x 1200mm be better.....

So many different materials its difficult to find which ones you require, I know its rather annoying but your help is much appreciated. I just don't want to order the wrong stuff considering its not cheap.

Cheers

 

[noseall]

Use Kingspan 9mm ply-bonded 100mm insulation deck.

Use 6" screws to fix it down.

 

[mpheating]

Use Kingspan 9mm ply-bonded 100mm insulation deck.

Use 6" screws to fix it down.

Is 100mm thickness enough? and do i fix it down straight onto joists or onto 18mm osb board

 

[noseall]

We fix it direct to 400mm c/c spacings.

Don't forget your firring strips.

B.C. are asking for 125mm now so you may need to add a further 25mm tight up against the underside of the 100mm stuff or fit 125mm from the outset like wot we do.

 

[cotswoldbuilders]

Use, Helical or Insofast fixings.

Either hammer in or use the adaptor in a hammer drill.

 

[mpheating]

http://www.insulationgiant.co.uk/p/...ation-board-td4126-126-x-2400-x-1200mm/778089

is that what you suggest?? its fairly expensive.

my office is 5m x 3m so will need around 6 boards..

£496.80 inc Vat

....and what are firring strips mate?

I came across the nails last night, finally found the website that shows you them in action and how they work, thanks for that

 

[noseall]

Firring strips or diminishing strips are what gives you the falls if you are fitting to regular level joists.

 

[mpheating]

ooh i see, i was going to get the joists cut with the angle built into them from my local wood yard...

im kind of getting a bit fed up of not been able to find the right materials, i looked into the roof board that i supplied a link to and the board attached is only 5.5mm thick, for the amount they want it sounds a bit naff, i dont mind paying for good quality materials but dont want to get ripped off.

if i did the following would it be ok...

18mm swb screwed down to joists
120mm celotex multi insulation on top
9mm swb board nailed through insulation, 18mm swb board and into joists
rubber roof on top, job done...

????

 

[noseall]

Sounds like a boon.

 

[mpheating]

Sounds like a boon.

whats a boon? a **** job lol

 

[noseall]

Top job.
Try not to over think it.

You will have your deck and you will have your insulation and you will have your waterproof layer.

All you need now is a VCL above the plasterboard and you are done.

 

[mpheating]

Waterproof layer? is this the foil that is on the insulation...


is VPL, vapour control layer? above plasterboard

i see you can buy moisture panel plasterboard from wickes and probably all merchants, would this be the stuff your talking about?

Its literally a garden office, but i want it to be warm and built to a decent standard, i have 100mm cavity walls etc and insulated floor. Sorry for all the questions im a heating engineer not a roofer.

 

[noseall]

Waterproof layer? is this the foil that is on the insulation...

...as in 'rubber roof'.

is CPL, vapour control layer? above plasterboard.

VCL = vapour control layer, correct.

i see you can buy moisture panel plasterboard from wickes and probably all merchants, would this be the stuff your talking about?

No, moisture panel is different stuff. You can buy foil backed plasterboard or instal your own plastic sheet etc. Foil taping all the inso' deck joints from below and/or using silicone mastic will help do the job also.