Which celotex

Joined
20 Mar 2006
Messages
107
Reaction score
2
Location
Cambridgeshire
Country
United Kingdom
I have a floating floor over block and beam and need to replace the insulation that the chipboard is sitting on. It's currently 25mm polystyrene. I've been quoted for celitex tb4000 but I'm not certain if that is the best stuff to use. I believe ga4000 might be the better product but I can't find it in 25mm. Anyone know the best stuff for this job please.
 
Sponsored Links
Joined
15 Sep 2017
Messages
28,027
Reaction score
2,034
Location
S. Uplands
Country
United Kingdom
To be honest.....any PIR insulation is fine, whatever brand. (Ectotherm, Celetex, Kingspan, Recticel)

I've never seen anybody care on building sites, despite architects specifying.

If there is any actual difference Id be interested to know.
 
Joined
2 Jul 2020
Messages
833
Reaction score
156
Country
United Kingdom
To be honest.....any PIR insulation is fine, whatever brand. (Ectotherm, Celetex, Kingspan, Recticel)

I've never seen anybody care on building sites, despite architects specifying.

If there is any actual difference Id be interested to know.

R value is not constant. For instance polyisocyanurate loses effectiveness as it gets cold. Sometimes you can find yourself on the bad side of this, especially if it's going to be under 10C.
 
Joined
15 Sep 2017
Messages
28,027
Reaction score
2,034
Location
S. Uplands
Country
United Kingdom
R value is not constant. For instance polyisocyanurate loses effectiveness as it gets cold. Sometimes you can find yourself on the bad side of this, especially if it's going to be under 10C.
I hadn't realised that, thanks.

I think the 2 celetex products the OP is mentions are both PIR.

not that 25mm in a floor is anywhere near sufficient.
 
Joined
2 Jul 2020
Messages
833
Reaction score
156
Country
United Kingdom
Yeah bad example with those products that are very similar. I can't see any difference other than the sizes offered.
 
Sponsored Links
Joined
3 Sep 2006
Messages
36,003
Reaction score
4,991
Location
West Mids
Country
United Kingdom
It's only worth insulating to the same value as the wall either side of it.

Edit
LOL; wrong post!
 
Last edited:
Joined
15 Sep 2017
Messages
28,027
Reaction score
2,034
Location
S. Uplands
Country
United Kingdom
It's only worth insulating to the same value as the wall either side of it.
I've often wondered about insulation.

If you insulate just one element, say the floor.....but not walls or ceiling, how much of an improvement do you actually make?

Is it like security - "only as good as the weakest link".
 
Joined
3 Sep 2006
Messages
36,003
Reaction score
4,991
Location
West Mids
Country
United Kingdom
It can be worth insulating whole surfaces and there will be benefits - ceiling most benefit, then walls and least benefit from floors. But for parts of these, there is not much benefit and can lead to a higher condensation or pattern staining risk where adjacent surfaces are significantly different temperatures
 
Joined
20 Mar 2006
Messages
107
Reaction score
2
Location
Cambridgeshire
Country
United Kingdom
Thanks for the replies. 25mm is obviously not really sufficient although better than nothing and I can't go thicker without creating a step into the next room as the whole downstairs is 25mm. Our house was built in 85 and the regs obviously weren't as tight then. We don't have a damp proof membrane under the polystyrene currently either.
My question was more about whether there is any difference in the amount of give or bounce I suppose rather than the insulation properties
 
Sponsored Links
Top