I live in low tech small town so I had to buy my own thermal camera to do my own survey of my house. I have rooms that the temperature changes rapidly so I suspect missing wall insulation. I’ve put off for years pulling the siding off my house to inspect, then came across thermal imagers. I have searched on the web for over a week for information on “rules” to use this device. (how I came across this forum). I found the certification training classes, but I just can’t afford the high price just to do my own house. I also found the Fluke videos, which I found relativity useless. I found one bit of information that I found very useful and that is the need for a 20 degree inside/outside difference to do a scan.
Which leads me to my first question; How long do the temperatures need to be at the 20 degree difference before I can get some good readings? I assume after sunset is the best time to scan?
I also want to check to see if my pitch roof is starting to leak, but I can’t view the entire roof from inside the attic. What is the ideal conditions to thermal scan from the outside? Like after a long rain and just after sunset of a sunny day? Will I get a good reading from the outside on a composition roof?
Also, how do I tell the difference between wet or missing insulation?
Any additional “rules” you care to share would be appreciated.
I already did the “normal” energy conservation stuff like added attic insulation, weather striping and used two dozen cans of foam and calking.
What kind of Camera did you buy? Are you planning on keeping it to use as a stud finder when hanging pictures or are you going to start providing others with Infrared services?
You don’t always have to wait until there is a 20 degree difference. Depending on how bad the problem is, how experienced in Infrared you are, or how high of a detection sensitivity your camera offers, than the less of a Delta T(temp. difference) is needed. The 20 degree difference is just a good overall recommendation(hence the reason I was wondering what camera you had).
Your going to have a really hard time verifying an interior leak by scanning the exterior part of the roof, atleast on a residential type roof. For the most part, you’re gonna have to figure out a way to atleast view the areas in question.
After you’ve been using the Infrared camera for a while you’ll begin to learn the difference between moisture an insulation from the patterns. In the beginning and always when in doubt, use a moisture meter. $29 at Home Depot or Lowe’s. Even when you think your right, use a moisture meter to confirm your right.
Be careful with sealing up every place you see any air intrusion. Homes have to breath fresh air just like we do. People are sealing their homes up way to tight causing other problems such as mold and low quality air. I would have someone come in with a blower door and make sure you haven’t sealed the home up beyond what’s recommended.
A tip for getting better images is changing the surface temperature of the walls before scanning them. If you start scanning and the walls have been virtually the same temperature for days than sometimes defects are less visible. You can stick a heater in a room and let it heat up the room changing the surface temperature of the walls by a few degrees. This will make it easier to see more potential defects within the walls. Same for the attic, try and get images when temperatures have just changed such as after the sun has been on it for 30+ mins or left it for 30+ mins.
Where are you located? I’m sure a fellow InterNachi inspector who’s close-by would be glad to speak with you and offer some assistance.
Around here, you’ll find that the more specific your questions are, the better chance they’ll get answered.
The rooms that are rapidly changing temperature are more likely to be doing so as a result of air leaks than missing insulation. Adding insulation to an air leak does nothing to solve the problem.
I would recommend that you have a blower door test done, first, to determine the air exchange rate of the house. An IR camera used during the blower door test will help you locate where the air is leaking and for you to direct a contractor (or yourself) to apply sealing efforts.
I bought the Flir i5. I planned on selling it when I’m done, they seem to hold their value on eBay. Why not get a better one in that case? The initial fund payout and it will sell quickly because of it’s overall lower price. I’m not a house inspector and I don’t have the time to be one.
75% of my attic is inaccessible, I can look at some of the roof though holes in the firebreaks, but the angle is almost parallel, so I won’t get a good reading unless the leak is large. I had the feeling outside might not work, but my deductive reasoning though if night time temps are low enough (with no wind) it would read as a cold spot. My attic is very well ventilated and would be impossible to heat artificially.
I commonly joke about suffocating inside my well sealed house. But between leaky exhaust fans and windows, plants and opening doors, air quality seems adequate. The RH is rarely above 40% inside, so mold is not much of an issue. Your point is duly noted though.
OK, 30 minutes dusk/dawn for temperature saturation. Here in the spring and fall, temps in a 24 hour span can change 50 degrees.
I already checked the InterNachi search for an inspector, there is only one, not that close and he doesn’t use thermal. The “Infrared Inspectors” thread shows zero in my state. As a side note; the forum may want to consider keeping an accurate, up to date list for potential customers that may pass though here, somewhere easy to find like the left margin. A web search for a thermal inspector brings up nothing useful.
Thank you for all your input Brandon, I appreciate it.
James, I suspect missing insulation, (My camera is still in transit) I have vault ceilings and the wall facing into the attic had NO insulation, now has 38R (two layers of 19). So if they missed there, it’s likely they skipped other places as well.
You could no doubt have flown in a knowledgeable thermographer equipped, trained and qualified to do energy audits for less money than it would cost to buy a capable imager for personal home use. You could have run a full blower door, duct leakage test and thermal imaging.
I would still recommend going this route unless you’re preprepared to spend a lot more time and money learning how to use your imager, even then you’d still be missing out on the blower door, duct blaster, etc. If you want to do moisture detection, you will need different additional equipment like a quality moisture meter.