Do I need to heat my underbelly to keep pipes from freezing?

[BigAdam]

I am working on replacing the floors and plumbing in my mobile home. Along with replacing some insulation and repairing holes in underbelly. I noticed that the original holes that were cut in the ductwork for the floor registers were sloppy and oversized. Is this intentional so heat can escape into the underbelly or just sloppy work. Are holes in the ductwork neccessary to heat the underbelly and keep the pipes from freezing?

[David Oxhandler]

It is a tough call to figure out what manufacturers were thinking about back in the day when gas and home heating were cheep. Today it seems that letting the forced hot air escape below the floor would NOT be very energy efficient. Hot air naturally falls. The price of home heating continues to go up. As long as your pipes are on the warm side of the insulation I would try to tighten up the homes interior as much as possible and keep the cost of heating down. Exposed pipes should be wrapped with insulation and heat tape.

For more information see:

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