Thermal bridge

[freddiemercurystwin]

So you did a google and found a pointless comparison table supporting grp roofing on a grp roof specialists website. Oh my, I stand corrected, I bow to your superior knowledge!

 

[bolst3r]

@freddymercurystwin

My bad, must make the damn images bigger... Only reason I thought about fibre wool instead of celotex is reading the info below on another post:

------------------------------
1) 1 m2 of 50 mm celotex will cost around GBP 6.50
2) 1 m2 of 100 mm Knauff fibre-wool from B&Q costs GBP 0.35

1) has a U value of 0.5
2) has a U value of 0.4

The fibre wool is 18. 5 times cheaper than the celotex and 1.25 times more efficient in its insulation properties.
------------------------------

As wall depth isn't an issue I figured fibre wool would be the best bet and when I costed for a thin layer of celotex over the timbers covered by plasterboard it worked out more expensive than insulated PB but that could be my dodgy eyes this time.

Sounds like ppl are steering me back towards celotex, perhaps 50-60mm in the cavity then 25mm over the wall timbers topped off with foil backed PB?

 

[freddiemercurystwin]

If you want it really warm use celotex in-between the studs instead of rockwool.

 

[bolst3r]

ok so back to original plan of foil backed celotex or kingspan, expandable foam in gaps then aluminum tape over the joints to make a complete vapor barrier followed by a layer of normal PB

 

[pred]

ok so back to original plan of foil backed celotex or kingspan, expandable foam in gaps then aluminum tape over the joints to make a complete vapor barrier followed by a layer of normal PB

I've got a feeling that Trade Point are selling Kingspan a lot cheaper than I last payed for Celotex.

 

[geraldthehamster]

I've got a feeling that B&Q are selling Kingspan a lot cheaper than I last payed for Celotex.

Unless B&Q have recently become more competitive I would go to a builder's merchant, or buy seconds.

Cheers
Richard

 

[bolst3r]

I did see a seconds place that did large loads of kingspan, still a shed load of money, excuse the pun...

 

[pred]

The last time I bought Celotex about 5yrs ago I'm sure I paid £100 for 2400x1200x100.
I just checked Trade Point, with vat 2400x1200x100 £41:28p or 2400x1200x50 £22:91p

 

[bolst3r]

mmm, not got a trade point account so difficult to check prices...

Was looking at seconds&co for approved Kingspan boards and they do Kooltherm foil/foil insulation boards 20mm for £7.

or a pallet of 1.2x1.2x80-100mm foil/foil for £120

 

[stuart45]

Try these for celotex. Ask for John.
http://www.aandainsulationservices.com/

 

[pred]

mmm, not got a trade point account so difficult to check prices...

Was looking at seconds&co for approved Kingspan boards and they do Kooltherm foil/foil insulation boards 20mm for £7.

or a pallet of 1.2x1.2x80-100mm foil/foil for £120

If you're a builder you can get a Trade Point card no problem.



http://www.trade-point.co.uk/search...ing&sProp=&dSort=relevance&catalogSpecificId=

 

[geraldthehamster]

mmm, not got a trade point account so difficult to check prices...

In my experience it's relatively easy to get a trade cash account at Travis Perkins, if you're buying a decent amount of stuff regularly.

Having said that, I got all the Kingspan for my dormer bungalow first floor works from Seconds & Co.

Cheers
Richard

 

[pred]

mmm, not got a trade point account so difficult to check prices...

In my experience it's relatively easy to get a trade cash account at Travis Perkins, if you're buying a decent amount of stuff regularly.

Having said that, I got all the Kingspan for my dormer bungalow first floor works from Seconds & Co.

Cheers
Richard

I've a problem with T.P. although there is one less than half a mile I find them expensive, my main supplier is Kellaway for building materials Trade Point for cheaper materials and Ashmead for roofing supplies.

 

[geraldthehamster]

I've a problem with T.P. although there is one less than half a mile I find them expensive, my main supplier is Kellaway for building materials Trade Point for cheaper materials and Ashmead for roofing supplies.

Your TP may vary. As with all suppliers, the prices you get will probably depend on the staff and your attitude to them.

Cheers
Richard

 

[bolst3r]

Yeah, used to have a TP trade card when I as doing a few jobs, now use a local builders merchant as they're pretty quick and a decent price.

Think I need to do all my calculations to decide what I need, then compile a list of everything and get all the suppliers to quote on everything as I need quite a lot of timber etc...

Just need to decide how I'm doing everything so I can draw myself up some plans