February 21, 20188 yr GRP can bond to cement/concrete. But it can also go horribly wrong. That is why test samples need to be done first. I t is not unusual to coat any unknown porous surface with cobalt accelerator, this just about guarantees that polyester resin will cure, but it can cause shrinking, which may not become apparent for a while. I cannot comment on ashfelt, it has not lasted that long on my shed roof, but on my Mother's flat roof it was over 40 years old (it is GRP now).
February 22, 20188 yr When laying up GRP on concrete (only once, to line a leaky pond) I used the G4 primer that CFS sells: https://www.cfsnet.co.uk/acatalog/G4_Primer_Sealer.html and that seemed to work very well. Not only does it improve adhesion, but it acts as a barrier that prevents any chemical reaction between the concrete and the resin.
February 22, 20188 yr G4 Primer can cause de-lamination after a time though. Not sure it it is caused by mechanical or chemical failure. I suspect the latter. thinking a bit more about this installation, with a few tonnes of concrete poured on to, there really should not be an issue (I forgot about the reinforced slab). It really comes down to the gutters, edges and corners details now to ensure that the insulation is total encapsulated. It is worth checking that the vacuum panels can withstand the styrene fumes.
February 22, 20188 yr 2 hours ago, pocster said: Any recommendations for a t & g cement board ?? Not much choice, but this stuff in the 22mm thickness is load bearing and has T&G joints: http://www.sts-uk.com/half-size-22
February 22, 20188 yr Author 2 hours ago, JSHarris said: Not much choice, but this stuff in the 22mm thickness is load bearing and has T&G joints: http://www.sts-uk.com/half-size-22 Yeah ; that’s about the most appropriate one I could find also .
March 6, 20188 yr Author After much waiting ..... architect still needs convincing so went straight to SE Assuming a 1.5 ton car and taking into account my roof/floor structure he quickly worked out point load at a tyre of 25kpa so well within the 150kpa of the vac insulation. Whilst my architect will require a sworn statement in blood from him that this is ok - I can get in and order !!! Edited March 6, 20188 yr by pocster
March 6, 20188 yr 4 hours ago, pocster said: After much waiting ..... architect still needs convincing so went straight to SE Assuming a 1.5 ton car and taking into account my roof/floor structure he quickly worked out point load at a tyre of 25kpa so well within the 150kpa of the vac insulation. Whilst my architect will require a sworn statement in blood from him that this is ok - I can get in and order !!! Whos providing the warranty or are you not having one ..?? If not the architect then it’s irrelevant what he says as it’s on the SEs PI insurance as long as you get it in writing.
March 6, 20188 yr Author 16 minutes ago, PeterW said: Whos providing the warranty or are you not having one ..?? If not the architect then it’s irrelevant what he says as it’s on the SEs PI insurance as long as you get it in writing. The SE ‘s head is under the blade ?
Create an account or sign in to comment