Seal the gaps
Use spray foam to seal air leaks and holes around plumbing fixtures
An easy way to save energy is to seal air leaks and holes where plumbing pipes run through walls in your home.
You can also check wall-mounted cabinets for plumbing holes or air gaps in the back. Fill any holes or gaps with spray foam. Wear protective gloves and use a damp rag for cleanup.
Source: Energy Information Administration and Dept. of Energy
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