How to Cover a Heating Pipe
- 1). Check your ductwork for leaks or other problems. Make sure all joints in metal ducts are tight and secure; fasten any loose ones with sheet metal screws, then cover with heat-resistant tape or caulking. Test metal hangers and other supports and repair any loose ones. With flexduct, check all seams and bends for leaks. Feel for any hot spots that would indicate heat loss through the existing insulation. Mark any problem areas.
- 2). Measure your ducts. Get exact height and width of metal ducts so you can figure out how much insulation you will need. Also look for any areas where there might not be space for regular insulation, such as a duct running close to a wall or between studs. In attics, check to make sure there are no gaps in exterior walls that might allow air to blow insulation off. Measuring is less important with flexduct unless you know you will need to seal a large section.
- 3). Choose an insulation type. There are many varieties, from fiberglass batting to loose cellulose (made from recycled newspapers). Pick one that is easy to use and has a high R value (the ability to retard heat loss). Use insulation with paper backing in any areas where people might come into contact with the insulation. You often can use regular fiberglass batting, which is used between studs in exterior walls. Tight spaces may require a thinner type. In attics, you can usually use a loose cellulose or other material. It may be helpful to cover loose insulation with some type of barrier to hold it in place. In crawl spaces, you'll have to cover both top and bottom of a duct.
- 4). Install your insulation. If using batting, cut lengths to fit around the ducts with a utility knife or large shears, then wrap it around the duct and seal with heat-resistant tape. Overlap seams and seal those with tape. Duct tape may be used for seams, but the tape's adhesive will loosen over time. If a duct runs between joists or studs, cut insulation to wrap as completely as possible and staple ends to the wood.
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