Celotex

oakwell · 14-01-2012, 08:23 PM

if u use this under the fibreglass can it rot down in time?

efficiencyman · 14-01-2012, 08:57 PM

I have used 100mm Celotex under my fibreglass the last 3 winters there is no sign of any movement, cracking, flaking or peeling and most important no water loss. It`s used in the building industry where it will often be damp, I cant see them using it if rotting or shrinking were ever to be a problem. It`worth it`s cost this wheather -- keeps my temps stable and heating costs down so low, I only use a few turns of Hepo pipe as a heat exchanger in my big Vortex -- The principal being if you dont lose it, you don`t need to put so much heat back in.

oakwell · 14-01-2012, 10:58 PM

Quote:

Originally Posted by efficiencyman

I have used 100mm Celotex under my fibreglass the last 3 winters there is no sign of any movement, cracking, flaking or peeling and most important no water loss. It`s used in the building industry where it will often be damp, I cant see them using it if rotting or shrinking were ever to be a problem. It`worth it`s cost this wheather -- keeps my temps stable and heating costs down so low, I only use a few turns of Hepo pipe as a heat exchanger in my big Vortex -- The principal being if you dont lose it, you don`t need to put so much heat back in.

cheers just was told today not to use it as it eventually rots and breaks down in time (no timescale given)

efficiencyman · 15-01-2012, 12:01 AM

Who said it rots ? and what is it likely to go like ? I have some exposed and it looks like it did 3 years ago!

oakwell · 15-01-2012, 12:46 AM

Quote:

Originally Posted by efficiencyman

Who said it rots ? and what is it likely to go like ? I have some exposed and it looks like it did 3 years ago!

someone who builds ponds advised me they dont use it as it can break down.

I aint sure just seeking confirmation it wount.

Ned · 15-01-2012, 01:50 AM

Celotex & Kingspan don't recommend it for use underground with ponds.

pmplumber · 15-01-2012, 10:05 AM

i know a few who have used celotex or kingspan but as previously mentioned neither manufacturer reccomends use below damp proof course so i wouldn't advise, saying that the ponds ive seen with celotex are still holding water so i dont know. i look for long term so would say a render is gonna last a lot longer and you will have no chance of movement but again, each to their own. let us know how you get on

oakwell · 15-01-2012, 04:19 PM

thanks for replys anyone else use it or got an opinion?

go54nke · 15-01-2012, 05:27 PM

According to the celotex site, all there products will not rot, but like said, they do not recomend installing below the DPC.

I have some on the back wall of the other pond which has been there, outside and exposed to the elements for 7 years, the top edge is discoloured thats all.

I used it on the new pond build and would use it again in the same way.

oakwell · 15-01-2012, 05:38 PM

the part of the pond that worrys me is the deeper part under ground level, which is quite damp and will prob keep damp later too.