We Made Our Own Water Heater Jacket To Conserve Energy You Can Do It Too And Save Money As Well
Did you know that a water heater jacket can save you at least 20% on your hot water heating costs? Did you know that your hot water heater is the single worst energy guzzler in your home? A home made water heater jacket costs little, saves a lot.
If you've been following these adventures, you will know that in our kitchen-dinette, we applied reflective foil insulation (also called "radiant barrier insulation") to our walls instead of the conventional vapor barrier that we used everywhere else.
We had several yards of the reflective foil left over, so we decided to wrap our hot water heater tank with it for insulation purposes.
How does reflective insulation work? When used as a water heater jacket, reflective foil insulation works the same way as it does in your walls: it reflects the heat back to its source. In this case, the heat is reflected back into the hot water heater.
Water heater jackets (or water heater blankets) come in kits made of various materials, and reflective foil insulation is one of them.
Hot water tank insulation kits usually cost between $25 and $40, but since the general consensus is that you can save at least 20% on your hot water heating costs – which represent about 20% of your total home energy costs – most people are willing to spend that kind of money on something that is merely a large piece of reflective foil, several pre-cut strips of the same reflective foil, and a small roll of tape.
You can buy these separately and save from $20 to $35, making this one of the cheapest and easiest DIY projects around.
We used the material that we had left over, but if you don't happen to have reflective foil insulation around, instead of buying a kit, buy a piece of insulation by the yard, and a roll of aluminum foil tape, at your local hardware store. ("Foil-bubble-vinyl" is the foil insulation type I had, and it's the one commonly used for water heater tank insulation kits, but any of the other types, from "foil-bubble-foil" to "foil-bubble-bubble-vinyl" can be used.)
NOTE: Duct tape, packing tape or masking tape won't do: you must get foil tape, or a special white vinyl tape that is designed for this purpose if you're concerned about the appearance of the finished job.
Without further ado, here's how we applied the water heater jacket to our own 40-gallon electric hot water tank.
HOMEMADE WATER HEATER JACKET, STEP-BY-STEP
1. Measure the girth of the water heater tank and cut four 5-inch strips of reflective foil insulation long enough to go around and overlap a bit.
2. Fold the strips in two along the length and apply them, spacing them as in the picture and fastening them with aluminum tape.
Avoid putting strips over the two element covers in case you need to access them at a later date.
Those spacers are the secret of the reflective effect of the foil insulation: the foil needs that space for the reflectivity to take place.
3. Measure the girth of the water heater again; this time, take the measurement ON TOP of one of the spacers strips, and add several inches for a good overlap. 4. Cut the foil insulation to the above measurement. I used a drywall square to draw a line before making the cut with scissors.
My roll was four feet wide, the perfect size for 40-gallon electric water heaters, and for 50- and 60-gallon ones too, I believe.
5. Apply the water heater jacket wall first, anchoring it to the spacers first.
Note that the foil side faces the hot water tank; that's so that it can do its job of reflecting the heat back into the tank, as explained above.
If your foil insulation has two foil sides, then it doesn't matter which faces where.
6. Then go around and finish applying the insulation, overlapping the seam and sealing it with a continuous length of aluminum tape from top to bottom.
7. Carefully cut around any pipes and seal with foil tape.
8. You will need to cut a slit to let the wire pass through.
Seal the slit with aluminum foil tape as well; you want your water heater jacket to leak heat as little as possible. 9. Now measure the diameter of the top of the water heater tank.
Add four inches to the number you get. 10. Cut a square of foil insulation using the measurement above.
Look around the house for a circular object of the same size. 11. As you can see, I didn't find a round object of the right size, so I simply cut the corners off the top piece of my water heater jacket.
12. Fold the top piece in four, snip off the point (to create the center hole), and cut a slit from one edge to the center hole.
You need that slit because of the pipe on top of your hot water tank. 13. NOT SHOWN: apply four strips (like the ones in No. 1 above) on the top of the hot water tank, evenly spaced.
14. Lay your top piece in place and correct the circle with scissors, leaving at least one inch overlapping the wall piece.
15. Tape the top seam and the edge all around, as shown.
16. Make sure the slit around the electric wire is well sealed up too.
17. The water heater jacket in place.
NOTE that I did not cut any windows in the water heater jacket where the element covers are (one at the top and one at the bottom). Those covers are removed when an element needs to be changed, or if the temperature needs to be adjusted (this should only be carried out by an electrician).
I had put some windows in, in a previous installation, but I never had to use them, so I decided that this time, if it ever became necessary to access those openings during the life of the hot water tank, that it would be a simple matter of cutting a hole in the right place (the covers are easily felt through the insulation), and covering it up again with a piece of insulation taped in place.
18. Wait! You're not finished! It's important to insulate the hot water pipes for a length of at least six feet, starting at the hot water tank.
You can do this by cutting strips of reflective foil and wrapping them around and around the pipes, but I had some pipe foam insulation left over from another job, so I used some here.
Foam pipe insulation is very inexpensive and it's available everywhere and in different sizes; elbows are available for covering the pipe angles.
19. I continued up from the water heater and along the ceiling, using aluminum tape to seal the joints.
Even though my pipes are of the new plastic type which doesn't lose heat as much as the old copper ones, because my basement is not heated I wanted to conserve as much energy as possible.
20. The excellent siteDIY Home Tips has additional water heating energy tips that anyone can implement. Have a look!
GAS WATER HEATERS
I have no experience with insulating gas water heaters. I would suggest you contact your supplier or the manufacturer for advice.
DOLLAR-BY-DOLLAR
I used leftover materials, so my cost was zero.
If you buy the materials separately, the foil insulation will cost you less than five dollars.
As for the aluminum tape, look around for the smallest roll at the best price – this stuff can be pricey.
However, you can use the foil tape for other insulating jobs, of course, such as insulating your furnace or ductwork, as in this project that I carried out in my previous home.
First, I taped all the joints with aluminum foil tape, which eliminated all the hot air leaks, then I insulated the furnace plenum and all the ductwork with reflective foil insulation, thus reducing my heating bills by 20%.
GREEN NOTES
Everything we do to conserve energy is green, but when something costs as little as this water heater blanket insulation project, well, there's really no excuse, is there?
