Tub Insulation - Foam

[jgrimes227]

BACKGROUND: In dealing with some frozen pipes, I came to learn that the Renovation Contractor (Eggleston Carpentry of Alexandria, VA) who remodeled the Bathroom in the home we purchased last year, had left an overhang space upon which the hi-end Kohler cast iron tub and supply and drain pipes were situated, UNINSULATED. Consequently the tub itself is ice cold, the water supply pipes to the tub and the toilet freeze, and the drain freezes. All this was un-noticeable from the crawlspace – everything looked hunky-dory because the under floor area of the bathroom was well insulated and parts of the area were concealed by what was ¼” plywood screwed to the bottom of the floor joists. Only after the pipes actually burst (and the ice pressure on the supply line to the toilet actually forced the compression fitting off the end of supply line – with a huge amount of water dumped on the floor in a very short period of time) and “Discovery” full-on priority did we find the uninsulated cavity that was fully exposed to the outside – finding it was by following the wind!!!!! Oh, the Toto toilet had been installed incorrectly as well – to the extent that the back of the toilet where the stop-valve is located, was jammed tight up against the wall so the valve could not be reached without removing the entire toilet. (Seems to be an archetypical case where a contractor, doing a job for aged and somewhat addled couple, just couldn’t keep his greed in check and just went all out screwing these people with shoddy work – there’s more but will save for another day.)

MY QUESTION: The Tub is a drop in with a surround that the Contractor failed to provide an access panel for. So what is in behind the surround is somewhat of a mystery. While I am under the floor putting insulation on the pipes, and fiberglass insulating this space I found, I thought that I would drill some holes in the floor upon which the tub rests from underneath and empty a couple of cans of flexible drying “Great Stuff” or some such insulating foam into this empty space. While the flexible version (blue can?) of Great Stuff purportedly remains flexible so that it does not exert the outward pressure that the non-flexible stuff does, I still have some nagging concerns about it – and thus turning to the collective genius of fellow members on any concerns or ideas they may have. I would gladly use fiberglass, but there is not now a practical way to put it between the tub and the surround now that it is all boxed in – except by using an expanding foam up through the floor underneath.

[frenchie]

My biggest concern is that you wouldn't fill the whole cavity, so it'd be a pointless waste of money. The only way to insulate properly, would be to pull the tub.

How come the contractor's not there, repairing everything free of charge? Or another contractor there, reapairing things, and the first guy getting sued to pay for it? The uninsulated space behind the tub, for one, is a code violation - pretty open & shut case.

[jgrimes227]

Well, to be honest I am just now dealing with the consequences of this guys work - getting the water back on and the kids back in the tub every night. I have called this guy (had to find out who he was through the county - at least he did pull a permit) but he didn't return my call. I am trying to figure out how to get him to consider paying something for this debacle - with gentlemanly pressure - but I am retired and love a good, well documented battle - was able to make Saab replace the engine in my Saab 9-5 Aero after they adamantly refused without having to go to court just by showing them I had them tightly by the short and curleys. I am also hoping that this guy will redeem himself - much nicer to win a battle by having the other party simply say, I screwed up, let me fix that.

I guess I was planning on only insulating the bottom and about 1/2 way up the tub. Getting the empty space sealed off and insulated will solve 90% of the problem - but getting the tub to just be comfortable and efficient to use was really all my intent was with the foam - just not done it before and good intentions and lack of indepth experience can be a toxic mixture. LOL

[jadnashua]

To be on the safe side, fill the tub with water before you use the foam, if you do. This will help ensure it stays down.

[frenchie]

I guess I was planning on only insulating the bottom and about 1/2 way up the tub. Getting the empty space sealed off and insulated will solve 90% of the problem - but getting the tub to just be comfortable and efficient to use was really all my intent was with the foam - just not done it before and good intentions and lack of indepth experience can be a toxic mixture. LOL

I see - we're in "worth a shot?" territory...

I think the blue can'd be safe enough, lifting-wise. I've used it on some pretty flimsy window frames, and it didn't bow them. But I could see the cavity I was filling, so it wasn't too over-filled, either. In your case, it'd be awfully hard to tell how much to use - how can you gauge when there's enough? Not like you can add any after the first application's set.

Is there no way at all to get access to the cavity? At least visual access, one person looking through a hole in the wall while the other fills from below? Cut open some sheetrock on one of the adjoining walls or something?

I'd put in an access panel, I think. You'll need it eventually, anyways, if anything ever goes wrong with the plumbing (and from the sounds of this guy, it's not unlikely). That'd allow you visual access, anyways.

Another thought: if you were to follow your original plan, and foam it "blind", how would you avoid foaming in the plumbing?