Insulating outside wall for an in-wall toilet
Khkiley
| Posted in Building Code Questions on
Hello everyone,
I am considering a wall mounted toilet that has the tank in wall. This would be on an outside wall. I am located in New Jersey 20 minutes west of NYC. How much insulation is required to prevent the tank from freezing ?
The tank would be one stud bay away from an uninsulated steam pipe if that makes any difference, I suspect it won’t.
Thanks in advance,
Kurt
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Replies
Kurt,
As a general rule of thumb, it's best not to include any plumbing in an exterior wall if you live in a climate with below-freezing temperatures.
If this is a new construction job, you should design your bathroom to be big enough to build a false (uninsulated) stud wall on the interior side of your insulated wall. The insulated wall should include an air barrier and adequate insulation to (at least) meet minimum code requirements, of course. Any needed plumbing can then be installed in this uninsulated stud wall which is located entirely on the interior side of your insulation and air barrier.
I did more or less what Martin suggests. My house has double stud exterior walls. The tank for the toilet is inside the inner stud wall, separated from the outdoors by nine inches of cellulose and the air barrier.
Thanks Martin and Stephen.
Its a retrofit with existing 2x4 stud walls, 1928. Tiny powder room, trying to squeeze out every inch possible.
The double wall is probably the way to go.
Thanks again.
Kurt
Yeah, bad bad idea to put a toilet tank in an exterior wall. A flooded house isn't worth 4" of floor space.