Insulating Hot Water Pipes

Your home’s hot water needs to travel from the tank to various locations throughout your house. In my case; I have copper pipes, but this is also applicable to Pex or C-PVC piping.

During the water traveling process, heat moves from the inside of your hot water pipe to the surrounding area. To give you a rough estimate — my home costs about $18.67 per month for hot water. I have a standard gas hot water tank. Electric tanks are generally more expensive to operate and therefore your pipe insulation savings will be higher depending on how you generate hot water. Any heat that is transferred through the pipe is literally wasted before it ever reaches your sink or shower. For this reason we want to stop the waste, save some energy, and make a more efficient domestic hot water system.


1. Heat is wasted while traveling from the hot water tank to the faucet/shower.

2. Insulating the pipes can stop this waste and allow your home to be more efficient and cost less money!

3. Pipe insulation costs roughly $2 per 6 ft section at the local hardware store.

4. Installation time is roughly 1 hour to complete the project.

5. You should save $3-$6 per month by adding insulation and your payback will be 1-3 years.

So, we begin this project in my basement. We need to find all the water pipes that are supplying hot water to various locations in the home. For me I have a dishwasher, washing machine, basement faucet, kitchen faucet, bathroom faucets x2, and a single shower. Turn on the hot water at the furthest location and allow it to run for 1 minute. This will heat the pipes up throughout your home and allow you to find the correct ones requiring insulation.

Now, travel into your basement and begin touching the hot water pipes (careful they might be hot). Mark the pipes that are warm and note there locations so we can add insulation to the correct pipes.

There will be three types of pipe insulation at the hardware store. Foam, foam self sealing, and rubber. For our purposes, I find the foam self sealing option to be best. The standard foam is roughly $.80 cheaper but you would need to add tape which lengthens installation time AND costs extra for the tape. Just buy the self sealing foam pipe insulation which cost $1.77 for me per 6 ft section at 1/2″ in size. Most of your pipes will be 1/2″ but make sure to check the various pipe sizes before making the hardware store trip.

Before insulation

Here is a picture of my basement hot water supply piping. These are 1/2″ in size and they are now warm to the touch. One of these pipes is for cold water…and doesn’t need to be insulated. Make sure to feel the pipes and find which ones actually require the insulation!

Hotwaterpipethermal resized
Thermal picture after running hot water: You can obviously tell which pipe is supplying hot water….The bright yellow is wasted heat

After finding your hot water pipes, fit a section of insulation around the pipe itself. For self sealing insulation — pull the plastic seal off and push the sections of insulation together. The insulation should now fit firmly around the pipe. I suggest starting with the sections of pipe that will fit full sections of insulation. Your insulation will not go past pipe connections and branches. You will need to cut short sections of your insulation to fit these smaller pipe areas.

Hot water pipes with insulation complete

Overall, This is not a difficult project and it is very inexpensive. This is a project that can be completed in limited time with a limited budget. After you have finished installing your sections of insulation — turn down the temperature of your water tank slightly and save some money on your utility bills.

Let me know if you have questions.

Insulating Old House Rim Joists

When you begin your journey of home energy conservation — heat loss is one of the largest factors in your monthly utility bill. The best strategy is to tackle “low hanging fruit.” Start the projects that are DIY friendly and offer a great bang for the buck. Remember that whenever you are doing an Energy Efficiency upgrade — you are also supporting a cleaner planet and saving some dollar bills every month.

So, let’s begin with Rim Joists. This is the section of your home, (Usually in the basement or crawl space) where the first first floor meets the foundation. If you have an old home like me, these will be open wooden cavities with some form of brick, stone, or concrete below. Here is a picture of my non-insulated rim joists.


I am lucky to have a basement with 8 feet of headroom. This makes working down here quite practical. Even if you have a dirty, musty, hard to work in basement….this job is pretty straight forward.

Next, I will show you a picture of this same rim joist. However, It is taken with my handy thermal camera (More on that tech item later)!


So you are probably thinking — “Wow Luke! Thanks for that great picture of colorful blobs.” But let me break down what we see here. Notice the two big purple squares? These are the rim joists sucking energy out of my home. Basically, the temperature of this area is far below the temperature of the surrounding home. My thermal camera is allowing me to see the drastic amount of heat loss taking place on this particular day (17F outside temperature).

The next step will be to “break” the flow of energy from inside to outside. To do this we need insulation!

MarkisonFoamCuttingI was lucky enough to have some 1.5 inch rigid foam EPS segments laying about. This would give me roughly r6 of insulation value. I used a standard box cutter to slice the foam to size (9.5″x14″ in my case) and fit them into each section. Similar foam can be purchased from your local hardware store and generally comes in 4’x8′ sheets. I would recommend you purchase a thickness of 1.5-2 inches for this project.

MarkisonRimjoistfoamnosprayNext comes the process of sealing the edges. We do not want air to escape around our new foam inserts! I recommend simple spray foam insulation in a can. This material is very easy to work with and relatively inexpensive to buy. I found that a single can will insulated 10 sections. My entire basement required 3-4 cans at under $3 per can. (I noticed cans cost $4+ at hardware stores….however Walmart had a ready supply for $2.77).


After sealing the foam edges, I now have a solid air seal. The combination of rigid foam and spray foam should significantly reduce the amount of heat leaving my home. Personally, i don’t like to paying to heat my yard during the winter…I would say this was a successful project overall. Estimated time of completion was 3-4 hours. Good Luck!

Here is a thermal image of one insulated rim joist next to an un-insulated rim joist. As you can see — the right joist with foam is significantly warmer than the left rim joist. This picture alone will inspire me to insulate the rim joists on every house I’ll ever own.

Written By:

Luke Langhals