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oups.com...
I have been helping my aunt excavate her back yard, in order to expose
hot water pipes, that run about 30 feet from the house to the garage.
Both the hot water heater and the natural gas boiler are in the garage.
The pipes are not insulated and are just about 18 inches below grade,
in Cambridge, Maryland (8 feet above sea level). Last year's heating
bills were astronomical, and my Aunt thinks that a lot of heat was
radiated into the frozen ground, before it ever reached her house.

My question is, once I expose the pipes completely, what is a good
method of insulating pipes in sandy and wet soil. Cutting the pipes are
not an option, thus we need something to retrofit. The insulation must
withstand backfilling, vast temperature changes, and moisture. What can
be used on this job?

Note: The house was built in the 1940's. In addition to fixing the
pipes, my Aunt is also insulating the house's ceilings and walls.



Are the pipes even worth saving? Unprotected galvanized would be almost at
the end of their useful life. Copper, may be in better shape.


I personally would call an spray insulation contractor. The two part stuff
that they use is a bitch to work with if you do not have the equipment and
they will give you a guarantee for their work.
Spray foam will adhere to the conduit and will seal the conduit from the
earth. I use this method for rigid electrical conduits when ever someone is
stupid enough to bury rigid. Metal in our soil is about a 6 year life span.
Once it has set up medium rocks do not even phase the insulation.