Spent time with a FLIR camera

[burnham]

So we have a FLIR camera at work, my boss let me take it home for the weekend so I could look around my house and see if I had any areas that were really bad. My house is a 1400 sqft cape built in '85. I just installed new windows, skylights, a roof, and blew insulation in the attic. (The attic is only half the length of the house, the remainder is cathedral.) In the past I air sealed in the basement and attic with spray foam. So anyway, as expected, my house looks really good through the lens of the FLIR camera. I'm seeing some cold areas around the AC vents (air handler is in the attic) and looking at the house from the outside I can see the foundation is really warm. I'm not really worried about the foundation as it's outside of the conditioned area. Today I bought some magnetic covers for the AC vents that I'll trim to size, but beyond that I guess there's not much else to do. It's a good thing, but I was kinda expecting to find some big cold spots when I started. I'm going to move on to finding a 4" LED recessed trim I like, so I can go buy 35 of the things and go about changing them out. Starting to wish I didn't go so crazy with lights in this place.

 

[woodgeek]

The knee wall areas in Capes are supposed to be hard to airseal. My sis's Cape has the AC ducts there and the cold air pours out of them in winter...is that what's up with yours?

 

[burnham]

I had the back side of the knee wall exposed when I removed the front porch ceiling last year. It was just studs and insulation, I see the backs of the outlet boxes too. I put a couple pieces of rigid foam in there, and used some spray foam too. I don't have any ductwork in that area. As far as the AC vents, I can feel some cool air coming out, and they look cold on the camera. I think there is air circulating through the system via convection, and I'm going to install magnetic covers on the vents and see how that does. I bought the magnets today at the Home Depot, about $8 for six of them. I just have to trim them to fit.

I bought and installed one 4" LED trim for the recessed in my shower. I didn't realize it's a 90w equivalent and 5000K. It's about 10X too white and too bright.

 

[Where2]

I bought and installed one 4" LED trim for the recessed in my shower. I didn't realize it's a 90w equivalent and 5000K. It's about 10X too white and too bright.

There are times, when I've been working under the diesels in my driveway that I'd give anything for that sort of lumens in my shower, rather than relying on the 9.5W LED and 13W CFL over the vanity.

 

[woodmakesheat]

I own a Flir camera that I bought for my work. I had one rather eye opening image from the several I took covering all four sides on my 1500 sq ft ranch. Methinks I need more attic insulation (that's the ridge vent)!

 

[woodgeek]

More likely, attic airsealing.

Try looking at the top of the insulation in the attic floor with the FLIR, and see if you can see where the warm air is coming up. I could track it with my IR thermo.

 

[woodmakesheat]

More likely, attic airsealing.

Try looking at the top of the insulation in the attic floor with the FLIR, and see if you can see where the warm air is coming up. I could track it with my IR thermo.

I may try that - easier said than done as my attic is accessible only through a hole in a bedroom closet. The insulation up there now is shipping peanuts - I have no idea if that has a decent R value but it wouldn't hurt to roll out some fiberglass. And there may be some leakage though I have no ceiling fixtures per se. I bet there is also some heat flowing from the wall where the stove is through the wall/soffit vents and into the attic. Let me go get the Flir.

 

[woodgeek]

You should also look for connections to the wall cavities and around the plumbing vent. Most of the big holes are invisible behind drywall.

 

[woodmakesheat]

OK, I may have found an issue with a former outside uninsulated attic wall that now borders the vaulted ceiling in the living room. I remember the insulation guy unhappily climbing through the hole in the closet to put insulation there - it appears that I could tighten that area up some. I'm guessing rodents aren't helping me here.

 

[semipro]

I'm not sure you're getting that air sealing is more important that insulation here as Woodgeek has mentioned. You can toss all the thermal insulation in there you want and it won't address air leaks.
Air leaks at the upper floor ceiling are the most critical because air pressure there is the highest due to the stack effect.
Air leaks from the living space to attic where wiring and plumbing are run, around vent stacks, scuttles, etc. It will benefit you to address those issues before adding more insulation. In some cases, its worth removing the insulation, sealing the leaks then re-installing insulation.

 

[woodmakesheat]

I just spent like 50 hours in labor rebuilding a drafty bay window. I used the thermal camera around the entire perimeter of the house and the only place where I thought the leakage was excessive was at the attic ridge vent. I did a 360 degree sweep in the attic and the highlight is the image I showed above. I'm looking for these air leaks, yet the areas on the cooler plumbing side of the house have a smaller delta T and I can't "see" them with the thermal camera. There is just one spot on the attic floor that shows up and I also plan to investigate that when I'm up there. If I can't see it with my thermal camera, and I can't see it with my eyes, then I'm kind of at a disadvantage in this conversation.

 

[woodgeek]

Nice find. That uninsulated wall looks hotter at the bottom.....are those wall cavities open between the conditioned space and the attic, or perhaps just stuffed with fiberglass (which does not airseal)? I had a wall like that in my split-level. I stuffed squares of fiberglass batts in tall kitchen garbage bags, folded them double and stuffed them in the cavity. Quick and easy.

I would look above interior walls...can you see the locations of you interior walls on the attic floor with the FLIR?