Published on May 17th, 2019 | by Scott Cooney0
Home Efficiency: DIY Thermal Imaging, LEDs, High Efficiency Water, & More
May 17th, 2019 by Scott Cooney
Your home uses more electricity and gas than you think it should, and that drives you nuts because you know it’s contributing to global problems, AND costing you hard-earned money. So, where’s the waste? Here, I’ll dive into some cool tools you can use in your home to diagnose problems and get them fixed.
Recently, I took a Level 1 Thermography course from the Infrared Training Center (ITC) on using thermal imaging. I was, perhaps, the only one in the course who didn’t work for a construction, electrical, or utility company. My interest was focused on learning enough to write this article to help you save energy at home through home efficiency. Alex Chrusciel of ITC said, “building specialists would find IR helpful in the identification of air leaks, insulation deficiencies, radiant floor systems, moisture/ mold identification, roof inspections, and HVAC systems.” And I concur, after taking the course.
Thermal imaging is pretty neat — you can use a camera to see heat. You can’t see through walls (or anything, really except really thin plastic or specialty materials), but if something on the opposite side causes a difference in temperature on the object you’re looking at through your camera, it’ll show that. So moisture building up behind a wall (a precursor to mold), or sediment accumulating at the bottom of a water tank will show through in that the top of the tank will warm up faster than the bottom during the heat of the day, and that’ll be clear in the image.
Seeing heat is handy for people looking to solve problems before timing belts break down or transistors blow up / catch fire, and I appreciate that! For the rest of us, some pretty basic thermal imaging can help diagnose problems in home efficiency, as long as we have the tool and know what to look for.
I took some photos recently using a Flir thermal imager attachment for an iPhone (about $200). Keep in mind, these are very qualitative. The ITC course goes much deeper, but for a lot of home energy uses, qualitative is pretty sufficient.
Here’s a water heater whose pipes need insulation. You can also tell that the water heater tank itself needs insulation, as it is clearly leaking heat, too (not as much as the pipes, but the surface area is much greater, and therefore the need is clear).
Here’s an interesting one now that summer’s here. Fans only really work to cool you off if you’re there to enjoy the wind chill from them. Otherwise, they not only use electricity and waste your money, they have a motor in them that generates heat and actually makes your house hotter. So turn ’em off unless you’re there to feel the breeze.
Here’s a pic that shows the attic needs more insulation.
Here’s a post on how to check your attic insulation.
Here’s a window leaking a lot of heat into an air conditioned home.
In the ITC course, you’ll learn much more in depth about how to use the cameras and interpret your findings. For instance, you’ll learn about T-refl, the temperature adjustment needed to compensate for reflected heat. It’s pretty neat, too. For a quick for instance, check out this picture.
Note how the two cups are very different in temperature on the camera? To get an accurate reading, though, you have to account for emissivity and reflection. The pieces of tape on the cup will “emit” heat at a different rates than the shiny metal cups themselves, so when you shoot an actual (quantitative) temp from the cups, you’ll get false readings, whereas the tape part will be more accurate.
But for home efficiency purposes, it’s sufficient to just use qualitative measurements most of the time. One major caveat is that, if the temperature outside is similar to the temp inside, you’ll miss a lot. So wait until it’s colder or hotter outside than inside to do any quantitative testing.
If you’re interested in getting a camera, Scott Sammons, the instructor in my course, said the minimum quality standard is a 120 x 120 pixel detector to do a “decent job.” He suggested setting the background temp (T-background) to 2 degrees above the air temp and calling it good. That will help compensate for any heat your own body generates while you’re taking readings. He added, “for air leaks, incorporate a blower door. These give total area of the leaks as well as highlight to the IR exactly where the leaks are.” Blower door tests are not inexpensive, but you can definitely start with a relatively cheap camera and go from there if things look bleak. Sammons also said, “a temperature difference is not necessarily a defect. Most walls do have studs, sill plates and top plated. They will show up [in thermal imaging].” So as long as you keep that in mind, other stuff you find might indicate real problems you can dive into deeper.
Other home efficiency quick wins: LEDs, faucets, & showers
LED (light emitting diode) bulbs now come in all shapes, colors, base types and sizes. The prices have come down, much as the costs of solar, wind, and other clean technologies have come down quite a bit, and when you look at the long term costs of an LED vs other types of lights, there simply is no comparison. Over the course of the life of an LED, it can save you hundreds of dollars vs. an incandescent equivalent. Silly not to switch.
Here’s a DIY home LED lighting audit tool I developed. You can see what you need, and even get a quote for replacing all your lamps.
The old wimpy low-flow showerheads have been re-engineered, and now for as low as $19, you can buy a beautiful, chrome, handheld high efficiency, high pressure showerhead. Trust me, they’re awesome.
According to the engineers at Hawaii Energy, these should save up to $250-300 per year for a shower used by two people. Water, heating for that water, and wastewater costs are all reduced, and there’s more hot water to go around in the house, making everyone happy.