This drawing demonstrates a simple and inexpensive method of taking heat from one building to another or to
protect underground pipes from freezing, by using 4"  flexible corrugated drain pipe for a conduit.

THESE METHODS ALLOW YOU TO REPLACE TUBES OR WIRES WITHOUT DIGGING

A BETTER METHOD IS TO COVER THE CORRUGATED PIPE WITH RIGID SPRAY FOAM RIGHT IN THE DITCH.

http://www.energycodes.gov/support/slab_faq.stm

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Soythane is a Do It Yourself, DIY, Spray in Place Urethane Foam. The use of Bio, renewable energy allows you to use renewable energy to save energy.
Soythane is a Do It Yourself Spray Urethane Foam with a hard skin, soft middle spray urethane foam. The B-side is made from regrowable energy. Soythane is closed cell to leave you with more insulation dollar per inch.

Go to http://www.soythane.com/  or call 1-877-772-9629
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