Thermal imaging cameras see temperature differences in the form of very long light waves the human eye cannot detect. Different temperatures are represented by different colors, and the camera can snap a digital picture of what it is looking at.
It is not point and shoot technology. The operator needs training to understand what the camera might be seeing. As I have said before, thermal imaging is sometimes science and sometimes art. Experience and interpretation of what is viewed is the key.
This thermal image represents hot and cold, relatively speaking. The color palette I pick for thermal image reporting is the one that shows orange, red and yellow to represent warm colors and blue, lavender and purple for cold.
There are many colors to choose from, including black and white, but this palette just seems logical to me.
A year ago I had an inspection where the entire roof space, all of the attic, and areas above the drywall on the upper level was covered with icynene foam insulation. It looks like root beer foam frothing out all over.
I have very little experience with this insulation. And I have never had the opportunity to look at it with my thermal camera.
Recently the same couple had me back to do a one-year inspection. I was happy too! I wanted to see what I could with the IR camera!
(WE ARE ALWAYS LEARNING!)
You should understand that the upper-level room, the fourth level, is one grand space, with two attic closets, each housing a different heat pump. One heat pump handles the third level and one the fourth.
The fourth level, an office, is closed off to the rest of the house by a door.
The thermostat there is set to 68F. The temperature is 74F. This level is essentially a turtle shell, surrounded by icynene.
The R-value (resistance value) of icynene is determined to be 3.6/inch. That is similar to fiberglass. Fiberglass batt insulation, the rolled stuff, has a stated R-value of 3.14-4.3/inch. But fiberglass has gaps and actually absorbs heat from the house when it is real cold outside.
Sprayed properly, icynene foam has no gaps at all. It is really very effective stuff!
Remember I said IR imaging is sometimes science and sometimes art. The color palette here might indicate a widely-varied temperature given the orange to deep purple color change.
The warmest temperature indicated in this image is 74.4F and the coolest a frigid 72.6F. So, just as Einstein said, IT IS ALL RELATIVE! What might look cold, with this palette, is not. The purple here just represents the coolest spot.
How effective is the insulation seen here? The temperature on the other side of this icynene layer is 14F! I don't know how deep the icynene layer is. I am told 12-14". This effective thermal barrier is doing very well indeed!
My recommendation: if you have the opportunity to select icynene foam insulation consider it! It is NOT cheap and the installer's experience is ESSENTIAL. As the Templar Knight said to Indiana Jones, choose wisely.
Jay Markanich Real Estate Inspections, LLC 
Based in Bristow, serving all of Northern Virginia.
Office (703) 330-6388 Cell (703) 585-7560
I am intrigued by TI. Have been investigating its possibilities. Just need to find a way to pay for the investment...
Happy Valentines Day...
Good morning Jay, I have never seen nor heard of icynene, but will remember it because of this post. I wish my house was covered in icynene, this past month has been brutal! It sounds like some very good stuff indeed. And so is that thermal imaging camera of yours.
Michael - I bought mine 7 years ago when prices were more than double for my camera now. It paid for itself in a few months with good marketing.
Andrea - I have two posts on it. It is interesting stuff. Read my posts and they will tell you a lot. But it is really hard to install in a house post facto! You would have to tear out all the drywall!
Jay, very cool photo and how wonderful this new building technology works. The great thing about this product is that it pays for itself over the years by decrease heating and cooling costs.
Love your analogy
Jay, Pretty "cool" :) I love the thermal imaging examples you're using in your posts. Bill
This is terrific information -- you continually educate us; thank you for sharing such valuable lessons.
David - this is a large house with monthly bills around $150 in the dead winter. I assume that dead summer the bills would be similar for AC. More temperate months those bills would be much less.
The difference between these bills and what they would have been with "regular" insulation would not be much. My house is of similar size, with three levels, and our monthly bill is about $200 dead winter.
That insulation cost them a lot of money! If the savings is $50/month in the severest (or even $100) and less in the more temperate months, I doubt they will live in the house long enough to recoup that! They tell me they decided on this insulation for the comfort while living there, not for any "savings."
James - which? Relativity?
Bliz - there is a lot to learn and that we inspectors can show!
You are welcome Tish. I don't this this insulation would do a lot for you in your area. These people maybe will break even in 35 years on their monthly "savings." Your area would take much, much longer!
Jay - I haven't used Icynene, but the reports I've seen indicate that it's very effective. Your camera provided a non-biased confirmation.
That's a pretty good display of how insulative it is John. While I can't prove it was 14F outside that morning, it was!
I see Icynene a lot up here, have for years. I believe foam isulations have limited applications and must be installed with caution. Icynene is an open cell foam there are also closed cell foams which are denser and thus have higher R values. My biggest gripe with this stuff is it burns very quickly. It meets the required fire resistant specs... barely. I have seen independent testing of this stuff, scary.
Jim - when I contacted the Berkeley Labs (see my follow-up post to the one linked above) Dr. Steiner did not bring that fire-rating stuff up with me. Closed cells are not used here because they are too stiff, and wood wants to expand and contract a lot here. You see closed cell used a lot by Mike Holmes, on TV. Different climate!
With everything around it and through it being wood, how does the minimal fire rating affect the spread of fire? Interesting info, thanks!
Icynene is just catching on here. This was my first new construction with it - a year ago.
Maybe you should start an online art gallery....I know you can come up with creative titles....this could have been a piece of the sky magnified,....and I just know inside the plumbing pipes and heating vents there is a masterpiece !
I see both types here, but for different applications. Closed cell is good for over a moist space, like a damp crawl or an addition built on piers without a foundation. Good for the rim joist too.
I don't think I've heard of this stuff before. I've got a home inspection today and am going to ask my property inspector if he sees much of it around here. I wonder if it's going to turn out to be carcinogenic?
We see this insulation up here a lot. You are right Jay, it's a different climate. We're north of Mike Holmes and here we recommend closed cell. It is far less conducive to mold growth as it will not retain moisture like open celled foam.
Fire code mandates that it be covered (gyproc, stucco or cement). The issue is that if burned or even heated by a nearby fire, it will off-gas deadly fumes that penetrates walls.
Nice IR example.
Jay,
In the hands of an untrained operator, it would certainly seem like there could be a problem. The two degree differential is pretty meaningless.
Never heard of this type of insulation before. Thanks for the info.
Rich
S&D - an online art gallery is an interesting idea! I bet the home inspectors on AR could get together and create a great one!
Jim - I've never seen closed cell except on TV. And I can see where it would be great for rim joists.
Wende - what isn't carcenogenic! ;>) Every time we turn around something else is going to kill us. Never mind that the average age at death somehow keeps rising!
My two previous posts on icynene are instructive.
Robert - thanks. Is gyproc the 5/8" stuff needed here for fire code blocks like garages or furnace rooms? I have yet to see closed cell, except on TV!
Richard - yes, sometimes we get faked out by places that seem moist, because of a cooler temp, but are not. It is best to identify locations with the camera and measure them with a moisture meter.
Jay, so far the reports back on this material are excellent---not bad for a "dream" material.
Yes Jay, gyproc is what you call sheetrock and 5/8 thick fire code drywall is the stuff. Every layer is 1/2 hour firecode rating, so a 2 hour rated wall has 4 layers (2 layers on each side of the stud framing). It is a white gypsum/chalk based product that is dried and pressed into the familiar paper wrapped 4 by 8 sheets. There are other sizes but that's the most common. Fire-code drywall has fibreglass fibre added to it (in the bad old days it had asbestos fibre). Moisture resistant boarding is made with a green or blue paper finish and (in New England states at least) is called 'blueboard.
There is a different, heavier product used around elevators and specialty areas. It's 1-1/2" thick, comes in 16", 18" and 24" width panels called core board.
Dur-roc is a brand name of the cement board made here that is used in bathrooms and other water prone areas, especially as substrate for tile finishes.
Locally we use the terms gyproc and durroc. (Dur-roc, 'dur' is french for 'hard' and 'roc' is french for 'rock'. So..cement board = hard rock.)
Spray foams:
Not everybody uses closed cell here but as people become more mold aware that's changing. As always there is a price and 'R'value tradeoff.
Inspectors call out the 1970s white polystyrene foam insulation panels in basements here for mold /water retention reasons.
Icynene foam is less visually identifiable as open or closed cell. You have to ask or look for product information.
Urethane foams are allowed but in limited amounts. Large volumes are a fire issue.
Well, Charlie, so far, so good. We will wait to see if it is actually the "dream" people are wondering.
Robert - I am familiar with all that, just never heard the word gyproc. (And when I got to college I had never heard the word 'hoagie' which they used for submarine sandwiches, and my college was only 50 miles from my house!) I assumed it was a regional word. I am always interested when I hear words that are new to me.
Nothing here is called blueboard, but greenboard, which has been used for decades, is losing favor.
Yeah. it's losing out here to the cement board. Ii's a better product for the purpose. I only heard the 'blueboard' term used on 'This Old House'.
The jury is still out on the 'dream' here. It is being used to fill cavities 100%. These enclosures have no provision for venting, not even for lumber 'seasoning' in place (drying out in other words). The worry is if there ever is any water intrusion you won't know a thing about it until it is a rotten mass that has to be demolished.
Keeping water out perfectly for any assembly, and forever, is not a trick that has been mastered.
Hi Jay-wow amazing information on something I have never heard of before
If you read my first icynene post, Robert, moisture was my concern then. I don't have enough experience with the product, or its longevity, to be able to make a real decision about it. And I haven't seen 'This Old House' in a long time!
Glad you found it Tim. Read the two previous icynene posts of mine to see what it's all about.
I'm a HUGE fan of that stuff, and I'm an even bigger fan of the denser version of that product; Icynene® is a brand of foam insulation that's commonly referred to as '1/2 lb' or 'open cell' insulation. It's basically a light and fluffy product that does a fantastic job, but there's an even better product out there: '2 lb' or 'closed cell' foam insulation.
Closed cell foam has an insulating value of 6.8 / inch, and will actually form a vapor barrier at a depth of 2". For older houses with limited space for insulation, or for homeowners with no vapor barrier in their attic, this is a fantastic solution, and the cost is about the same as open cell foam.
Good point about reading the temperature range on your IR images.
Edit: Gee, I'm a little late to the party. I just read all the other comments about closed cell foam.
It's cold there Reubs, you are allowed to be late, although I have it on one authority that yesterday it reached summer temps!
I understand from the foam guys around here that closed cell is not used because it does not allow the wood to expand with heat. That causes gapping and structural problems. Jim Q's point about using it in crawl spaces on rim joists might work around here, but again, I have not seen it.
You probably should stick to promoting dryer lint. Works great for your by-pass surgeries in the attic.
Looks like that stuff really works! I was guessing from the photo that it didn't at first, until I read about the range of the temps.
I wonder if you think this will work for sealing up attic bypasses, as Reuben talked about?
Jeremy - it is put up onto and under the sheathing and not on the floor where the bypasses occur. So yes, it will work to prevent ice damming.
So they could leave the floor insulation in place, and just add this to the roof sheathing underside. Ok.
Jeremy - in this house there was no floor insulation! The exterior walls were fiberglass and the roof, a turtle shell essentially, was icynene. There is no venting for the attic space whatsoever!
Jay - you sure got it right about summer temps here. Today it was in the low 40s! Downright balmy. Good to know about the closed cell foam.
Jeremy - absolutely. Foam insulation does a fantastic job of sealing up attic bypasses. It's too bad that we only use R-values to quantify the effectiveness of insulation. When you factor in air leakage, the effectiveness of most insulations will go way down. You don't get this drop in effectiveness with foam.
Jay is the wood swelling you are talking about actually directly from heat itself or is it hygroscopic swelling from water absorption because of the high humidity that accompanies the high heat conditions?
if it is hydroscopic in nature then the closed cell spray foam insulation will have a different effect. It will create its own vapour barrier with a uniform 100% coverage. Under a full application of foam, wood framing will not be swelling as it is isolated and encased in the foam.
Unless I'm missing something, wood does not expand from heat itself. In an arid environment and heat wood will actually shrink, even pyrolize due to water loss.
Montreal gets just as hot and humid in the summer as Virginia, it just lasts longer in Virginia.
Reubs - glad you are enjoying it! You are right, stop the air flow and that is as good as, if not better, than worrying about R-value. Crack a window at night and see how effective the foam around it inside the walls is working!
Robert - yes, heat and humidity. Wood windows here often swell to the point of not opening! We have 20-25 days over 100F (38C) with really high humidity. I played minor league baseball and on cloudless days with temps of 98F the humidity would be almost as high! I lost 12-15 pounds per game.
According to my friends at Berkeley Labs (see my second icynene post a year ago) soft woods swell much more than hardwoods and open cell foam does not restrict humidity movement like closed cell. They recommend that closed cell foams not be used in humid areas.
An interesting article - http://www.fpl.fs.fed.us/documnts/pdf1995/manta95b.pdf
Hi Jay, thanks for getting back to me. I've gone back to your prior blogs (not that easy to find btw) and read them and read the comments.
I appreciated the article too. You might be interested in the article on the subject in the most recent issue of 'Fine Home Building'. (March -2011)
Sorry Robert! There are links to my previous icynene blogs in this one! I'll check out the article too.
Hi Jay, I woulkd like to use a "thermal imaging camera" but with all the lawsuits from "homesafe".
I will wait to see what happens with all those first.
Best in 2011
Clint McKie
Haven't heard a word about any such lawsuits. Where can I find out Clint? Not that it's going to change what I do, but I am interested.