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spray foam for under a jetted tub

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rlz

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Dec 12, 2012, 7:35:41 PM12/12/12
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I installed a jetted tub about 15 years ago. It came attached to its
own wooden supports on top of 3/4" plywood. I basically just had to
put in place and screw the plywood down. Since that time, I've been
fighting the caulking around the edge of the tub and the wall tiles.
It seems that when the tub is filled with water and someone is soaking
in it, the extra weight causes the tub to settle down. This has
caused very small hairline cracks in the caulking.

I heard someone say to get some spray insulating foam and spray it
under the tub between it and the plywood. I'm not sure if there is a
specific type of spray foam that would work best. When I went to
Lowes recently, they had two different types, small gap and wide gap.
I'm not sure if either would work here. I think the spacing between
the tub and the plywood is about 3-4 inches.

Someone else mention using a very dry mortar and then packing it in
with the tub empty and letting it cure, I'm not sure if this is a
good idea either.

Any ideas?

Oren

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Dec 12, 2012, 7:51:32 PM12/12/12
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On Wed, 12 Dec 2012 16:35:41 -0800 (PST), rlz <ro...@ellzey.net>
wrote:
I used expanding foam 8 years ago when I put a jetted tub in.

The _trick_ is to fill the tub with water first. Then spray the foam
under the tub, allow is expand and cure BEFORE you drain the tub. I've
not had any problems whatsoever. The foam is faster than mortar. It
provides a great deal of support. You will notice the tub bottom will
not flex from a persons weight, That flex is what causing the cracks
in the caulk.

I used two cans.

Good luck

cl...@snyder.on.ca

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Dec 12, 2012, 7:54:14 PM12/12/12
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On Wed, 12 Dec 2012 16:35:41 -0800 (PST), rlz <ro...@ellzey.net>
wrote:

You want "low expanding" door and window installation foam. If you
use the regular stuff it will try to push the tub up to the ceiling.
I used it when I helped re-install a friend's tub (his brother, a
plumber, had installed it level instead of having the drain end down
1/8 inch or so - so it never drained properly). The foam also keaps
the bath warm a lot longer.

Oren

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Dec 12, 2012, 8:08:15 PM12/12/12
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Filling the tub first (full), will prevent the tub from lifting. I
forget which type of foam I used. It did take two cans.

cl...@snyder.on.ca

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Dec 12, 2012, 9:24:08 PM12/12/12
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The high expanding foam can create enough lift under the area of a
tub to lift several tons. If it doesn't blow the sides out first.

rlz

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Dec 12, 2012, 10:19:48 PM12/12/12
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On Dec 12, 7:24 pm, cl...@snyder.on.ca wrote:
> tub to lift several tons. If it doesn't blow the sides out first.- Hide quoted text -
>
> - Show quoted text -

Thanks for the replies. I'll try to fix it this weekend.

dadiOH

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Dec 13, 2012, 8:36:51 AM12/13/12
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Nothing wrong with mortar, it works fine.



--

dadiOH
____________________________

Winters getting colder? Tired of the rat race?
Maybe just ready for a change? Check it out...
http://www.floridaloghouse.net


Oren

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Dec 13, 2012, 6:26:27 PM12/13/12
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On Thu, 13 Dec 2012 08:36:51 -0500, "dadiOH" <dad...@invalid.com>
wrote:

>> Someone else mention using a very dry mortar and then packing it in
>> with the tub empty and letting it cure, I'm not sure if this is a
>> good idea either.
>
>
>Nothing wrong with mortar, it works fine.

...on a new install?

Foam is a great solution in this case - I bet.

dadiOH

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Dec 14, 2012, 9:34:47 AM12/14/12
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Oren wrote:
> On Thu, 13 Dec 2012 08:36:51 -0500, "dadiOH" <dad...@invalid.com>
> wrote:
>
>>> Someone else mention using a very dry mortar and then packing it in
>>> with the tub empty and letting it cure, I'm not sure if this is a
>>> good idea either.
>>
>>
>> Nothing wrong with mortar, it works fine.
>
> ...on a new install?

After the tub was set.
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