I had the copper pipes leading to the kitchen under the deck sprayed with foam.
I cannot recall if it was open or closed cell spray foam. The reason I had them covered with spray is because the pipes under the deck were exposed to the outside cold air and always in danger of freezing in the winter.
I now plan to add additional mineral wool insulation and cover everything with siding. My concern is whether the foam insulation will be harmful to the copper pipes or the drinking water supply. Your comments will be greatly appreciated.
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Replies
No
The foam shouldn't harm the piping or contents, but that's not your potential problem. It sounds like you have an outside kitchen area, for summer use, and it has a water supply to it. If that's the case, then you need to think about what is on all sides of the now insulated piping. If you have outside air all around the insulation, above and below the deck, and too long a run of piping for conduction from inside the house to keep the end of the piping run from freezing, then all the insulation does is delay the freezing. If the configuration is as I described, why can't you just shut off the supply to the outside kitchen and drain the outside piping for the winter? I suspect there is something about what you have there that we need to know to comment further.