Good afternoon all,

 We were called in to do an energy audit on a log home.  Very nice house but with ice build up and back up in winter and moisture on the interior main beam during summer.  We could see with infrared and visual inspection that there wasn't enough insulation but, with it being a log ceiling, we weren't sure how do address this.  We shared with the home owners that it looked like the roof had to be reconfigured to allow us to put in closed cell.  So, basically a new roof.  Has anyone ever encountered this before and what was the solution?

thank you!

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Hmmm interesting that infrared can tell you exactly how much insulation... More like you have some thermal anomalies which show some issues which require more looking into. For typical issues like this you need to take existing roofing off & get down to T&G boards (assuming this style) / sheathing (if not other) & build it back properly carefully insulating the he11 out of it - recommend at least two layers offset & taped

Thank you, Sean.  Infrared did not tell exactly what we needed, only that our suspicions were correct.  We shot the house from the outside.  Anyway, we're still at taking off the roof, eh.

Yep especially if you got water issues as the insulation that was there is now essentially shot / water trapped & there maybe more issues you can't readily see (though infrared can help in that regard)

This is like those BPI "Stump the Chump" problems where there is not enough information to answer the problem, so the person with the best guess wins.
It is most helpful if posters noted the pertinent information. In this case, that would be things like, what kind of ceiling? (I am assuming cathedral?), what is the ceiling covering? (T&G? sheetrock?) what kind of roofing? (asphalt shingles?, shakes?, standing seam?) Is there a flat attic? Where is the house located (city/state)?

Almost all of the log homes that I have encountered around the Central Vermont area have standard 2x spruce rafters with fiberglass batts. One had a SIPS roof and another a "living roof" (sod and grass). Many of them have T&G ceilings which leak air.
As for infrared, I rarely look at a house from the exterior due to the many variables that could affect the IR. (I completed a Level I thermography class with Snell Infrared about 10 years ago, and I use IR a lot).
You need to know the structure of the roof in order to come up with a proper diagnosis and prescription.

"The more you look, the more you see", and "If you don't look, you don't see".

This is like those BPI "Stump the Chump" problems where there is not enough information to answer the problem, so the person with the best guess wins.

It is most helpful if posters noted the pertinent information. In this case, that would be things like, what kind of ceiling? (I am assuming cathedral?), what is the ceiling covering? (T&G? sheetrock?) what kind of roofing? (asphalt shingles?, shakes?, standing seam?) Is there a flat attic? Where is the house located (city/state)?

Almost all of the log homes that I have encountered around the Central Vermont area have standard 2x spruce rafters with fiberglass batts. One had a SIPS roof and another a "living roof" (sod and grass). Many of them have T&G ceilings which leak air. As for infrared, I rarely look at a house from the exterior due, especially roofs, due to the many variables that could affect the IR. (I completed a Level I thermography class with Snell Infrared about 10 years ago, and I use IR a lot). You need to know the structure of the roof in order to come up with a proper diagnosis and prescription.

"The more you look, the more you see", and "If you don't look, you don't see".

Thanks Brad.  You're correct on the missing info.  I do the customer service work and help do the actual audits but the boss does all the inspection work.  It is T&G and a cathedral ceiling.  I'm just trying to help the folks out and see if there are other options out there.  We're in western NY.

 I don't get how someone can sell a log home or a modular home in this area with the BS insulation they put in there.  At least tell the folks that it should be foam and FG batts and give them a price and let them decide.

Agree that its hard to help without more information. Pictures? IR images? Do IR images show air bypass or insulation voids? or both?

If its T&G with exposed beam rafters it would suggest the T&G is the roof sheathing as well as the finish ceiling and all existing insulation is outboard of that and is probably foam board. If that's the case, best to tackle from the outside and problems are likely due to foam board joints being leaky (perhaps broken seal from movement). If that's not possible, could talk owner into a new interior look and use the rafter cavity to do it right on the inside and then install new finished ceiling, T&G or other.

If its T&G continuous across the ceiling and no exposed beams there is probably dimensional 2x rafters behind it with crappy fiberglass/poly and its probably vented soffit to ridge (is it?) and leaky as all T&G is. In this case, could gut it or do it right from the T&G inward with air impermeable board insulation sealed to T&G, strapped and then install new finished ceiling.

I think either way you are looking at either a new ceiling or a new roof unless IR shows only air bypass and not voids and you want to just clear caulk a mile of T&G joints and hope for the best. I'd also double what was said earlier that you investigative if moisture issues are more severe than meets the eye before covering it all up with something new!

Best of luck!

I would look to stop air from penetrating the ceiling. I would guess hot air is able to rise through penetrations in the ceiling or the ceiling itself, washing batt insulation. If you are going to remove the roof and use closed cell foam it will fix the issue. closed cell pretty much fixes all problems. Another option is to use a clear coat polyurethane to seal the ceiling. Like finishing wood work.  Then caulk in all ceiling penetrations.

I built one of these two decades ago. From inside to outside....

Log main beams, 2 x 6 T&G ceiling, 6 mil poly sheeting, then 14 inch TJI spacer/rafter with R-38 batt and 2 inch air space, then roof deck with soffit and ridge vents.

We ran the TJI rafters out 3 feet past the side wall for summer passive solar shading on the windows, so we had the space to extend the fiberglass batts well outside the sidewall -- no cold top plate/top log.

We were wicked careful to keep the VB solid. The insulator shoving the batts in had a roll of tape on their wrist, with strict instructions to tape every flaw found.

In southern Wisconsin, this system worked. No icicles, no ice dams, even during the winter (2000-2001) that saw ice dams all over the southern half of the state. That's the winter I shot an ice dam photo that's STILL being used in a physics textbook.
Thank you everyone. Homeowners are removing the roof and we are going from there. I am going to speak with the log home company and go over some of the ideas offered here.
Bob

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