How-to
How to Insulate Hot Water Pipes
🇩🇪 Diesen Artikel auf Deutsch lesenInsulate accessible hot water pipes, especially the first few feet from the water heater and pipes in unheated basements or crawl spaces. Pre-slit foam sleeves are easy to install. According to the US Department of Energy, insulated pipes can deliver water a few degrees hotter, letting you lower the water heater setting.
Hot water loses heat as it travels through uninsulated pipes, especially in cold basements and crawl spaces. Insulating pipes is one of the cheapest energy upgrades available.
Step by step
- Find accessible pipes
Start at the water heater and follow hot water pipes through the basement, crawl space or utility room.
- Measure pipe diameter
Measure the outside diameter or check markings on the pipe to buy the right sleeve size.
- Cut sleeves to length
Use a utility knife to cut sleeves; cut angles at elbows so joints fit tightly.
- Fit sleeves over the pipes
Open the pre-slit seam, press the sleeve onto the pipe and close the seam.
- Seal seams and joints
Use the sleeve's adhesive strip or tape seams and joints with duct tape or insulation tape.
- Keep clear of the flue
Keep foam at least 6 inches away from gas water heater flues; use fiberglass wrap near heat sources.
Choosing insulation
| Material | Notes |
|---|---|
| Polyethylene or neoprene foam sleeves | Cheap, easy, pre-slit; most common |
| Fiberglass pipe wrap | Use near water heater flues where foam could melt |
Match the sleeve's inner diameter to your pipe size (most household pipes are 1/2 or 3/4 inch).
Bonus: protect cold pipes from freezing
Insulating cold water pipes in unheated areas reduces condensation in summer and helps prevent freezing in winter, though very cold areas may also need heat tape rated for pipes.
Shower Cost CalculatorWater and energy cost of your showersTry the calculator →Frequently asked questions
Should I insulate cold water pipes?
In humid areas it reduces condensation drips, and in unheated spaces it helps prevent freezing.
How much does it save?
Savings are modest but the cost is very low, so payback is quick. You also get hot water at the tap faster.