Gap filling foam impervious to water?
 

Is gap filling polyurethane foam waterproof?

Need to fill a >1" gap at end of bath. Gap nicely covered with moasic tiles but joint had cracked with movement or silicon seal had gone with time and water had saturated ply underneath I had previously filled gap with and tiled over, dragging clour out of wood and up through grout (believe it or not!).

So I'm planning on filling gap with foam and topping over that with the moasic. If joint fails again am I asking for trouble? I think not as although aero like I think the foam is impervious. Correctamundo?

[Its a damp area but not submerged, btw]

Re: Gap filling foam impervious to water?
 

Hey your the clever one. Work it out yourself.

I've used it to block holes from the outside and it seems fine. However, that is not to say I know that it is waterproof, just that it hasn't let the weather in yet.

Re: Gap filling foam impervious to water?
 

not entirely waterproof stuff Doc, as it expnds it leaves ltlle gaps here n there.

i'd use that first, then a shi* loads of clear silicone sealant on top which is then smoothed over and flat with a wet blade edge of something suitable like a butter knife or spatula and then allow to dry. they fill any remaining gaps with more silicon sealant.

I tend to go over what i'm filling with the sealant and then trim off excess with a very sharp blade myself.

HTH

Re: Gap filling foam impervious to water?
 

Ta. :smt023

Vile stuff though.

Re: Gap filling foam impervious to water?
 

Whatever you do, DO NOT get it on your hands. I was using it at work and the gun buggered up and started spraying the stuff everywhere. Took me days to get it off my hands (loosing some skin in the process). It is still stuck to my work trousers to this day, and thats after loads of times in the washing machine.

Re: Gap filling foam impervious to water?
 

No comment on the foam, but I will only use Dow Corning silicone sealants in bathrooms/kitchens now. They are so much better to apply and reliable in use than anything else I've used. Sanitary grade 785 is what you want, 786 food safe stuff would be OK if necessary.

Plumbers' merchants often stock it (Plumb Centre etc).

Re: Gap filling foam impervious to water?
 

yeh clothes also do not like this stuff !!!

HTH

Re: Gap filling foam impervious to water?
 

My clothes loved it, in fact they're kinda attached now!!

Re: Gap filling foam impervious to water?
 

yeh okay i'll give you that one ;):smt038

Re: Gap filling foam impervious to water?
 

Get a proffesional in.



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