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|BPA Home EE Home Energy Tips Do-It-Yourself Home Weatherization Guide Insulating Pipes and Ducts|
Insulating Pipes and Ducts
When insulating attics, floors over unheated basements, or crawl spaces, be sure to insulate the pipes and heating ducts located in these areas, too. Ducts are the rectangular or cylindrical sheet metal passageways that carry heat from the furnace to your rooms. Unless they are insulated, they can waste much more heat than they deliver. Water pipes can be protected from freezing and heat loss with insulation.
To Insulate Pipes and Ducts, You'll Need:
Tools and Equipment:
Insulating Heating and Air Conditioning Ducts
Securely tape any cracks or gaps and all joints in the ductwork with duct tape before you install insulation. Up to 30 percent of furnace heat is lost through cracks and seams in the duct work. Check to make sure that joints are securely joined (fasten any loose joints with screws) and that the metal or wire supports joining the ducts to the structure are in good repair.
For rectangular ducts, cut sections to a length equal to the circumference of the duct. Wrap the lengths around the duct (Fig. 5.1), taping them securely along their entire length. Tape the ends and edges of adjoining blankets together along their entire seam.
Insulating hot water pipes not enclosed by floor insulation helps minimize heat loss. In the winter, it will help keep cold water pipes from freezing. If you live in a severe climate, consult your utility to find out whether greater pipe insulation R-values are recommended for your area.
Before installing pipe insulation, clean dirt and rust from pipe.
If you use pipe insulating "sleeves", apply them according to manufacturer's directions. (Fig. 5.4.) Apply batt insulation by wrapping pipes in a spiral fashion, overlapping each successive layer by half (Fig. 5.5). Wrap the insulation as loosely as possible; compressing it reduces the R-value.
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