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staceyneil

Insulating the bathtub.... Flyleft? Others?

Stacey Collins
14 years ago

I just read flyleft's mention of insulating the tub on another post, and I would love some details of how folks have done this.

We're installing a soaking tub (no jets) into a tiled deck. The "alcove" is 6'4" long, so there's about 8" on each end a couple inches on each side of the tub. Two walls are exterior walls, and since we live in Maine, I want to be sure I insulate it as well as I can.

So, how did you do it?

I can't really picture how to get a good tight amount of insulation in there without it being in the way when you drop the tub in... because the deck and apron will be all tiled and finished before the tub gets dropped in. The only access will be through the tub's hole before it goes in, and through a panel on the short end (through an adjascent wall) that's the valve access panel.

Comments (9)

  • sweeby
    14 years ago

    Mongo - Is your spray rig something special just for foam insulation? Or is it a multi-purpose spray rig that can be used for foam, then cleaned up and used for something else later? (We love spray foam insulation and Hubby's got a few spray rigs...)

  • Stacey Collins
    Original Author
    14 years ago

    Hey thanks so much, Mongo! That's great advice. We will actually have some 2" polyiso left over from insulating the floor, so maybe I will use that, or a combo. Thanks for the ideas!

  • mahatmacat1
    14 years ago

    Well, for those of us without mongo's advanced spray technology :), I just used two spray cans on the back and sides of our master bath tub as far as it would go, and then used other methods too. One was to fill all the gaps in the apron/deck framing with thick polyiso sheets (available at HD) cut to fit tightly, and then I filled the cavity from two open holes with loose cellulose I pushed in with long sticks until I could fit no more. There was probably some airspace left, but I gave it my best shot. I was determined :)

    With DD's tub just yesterday, I sprayed two cans on the back, then put an R-13 fiberglass batt around the back and sides as far as it could go. The walls in the alcove (not a deck installation) were also insulated. That's about as much as I could do on that one.

  • mahatmacat1
    14 years ago

    NOTE: the spray expanding foam I got was the less-expanding type for gaps & cracks, not for huge spaces. You don't want to be potentially distorting the tub. I forgot to put that in my original reply.

  • advertguy2
    14 years ago

    I did our drop in tub with canned spray foam (5 or 6 cans) before installing it. Turned it upside down on some sawhorses and went to it. Took a couple of applications to get it uniform. I also lined the inside of the cavity with mineral wool (readily available and same price as fibreglass here in Canada). My wife seems to think it made a huge difference in the heat retention of the tub. We had the same model in our old place and it wasn't insulated.

  • mahatmacat1
    14 years ago

    That's a very interesting controlled kind of anecdotal evidence--thanks, advert.

  • MongoCT
    14 years ago

    sweeby, yes, it's a special gun and set-up just for shooting two-part closed cell polyurethane foam. It's actually a commercial rig that I bought years ago when I had an absolutely monstrous project to do.

    Now if you have a lot of board feet of foam to shoot, there are smaller "DIY" spray systems out there, these two have been around for a while and have a good track record;

    Fomofoam.com
    Tigerfoam.com

    There are also some that shoot soy-based foams if you're into that "green" stuff. ;^\

    Some have reusable guns, others have disposable ones, so read the fine print carefully.

  • PRO
    FoamBeak
    6 years ago

    The easiest way to accomplish this is to check out www.insulatedbathtub.com