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Any idea what the R Value might be? (i.redd.it)

submitted by TakeMyPulse

1970's house, with a garage added on at some point. 2x4 Studs. I don't have alot of experience with insulation (other than past reno's). There's no way this is R12 or greater, right?

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[–]Horus773 12 points13 points  (8 children)

divide the thickness of the wool, in meter, by 0.035. For example 15 cm of wool is 0.15 / 0.035 = 4.3

[–]TakeMyPulse[S] 7 points8 points  (7 children)

Thank you very much!

Edit - Looks like R Value of 7. This is an exterior garage wall, so I'll be replacing it.

[–]Correct-Award8182 2 points3 points  (0 children)

More like an r value of 13. Roughly a bit less than 4 per inch.

Depending on your energy zone, it may already be code compliant. Also, that's fairly modern product.

[–]macavity_is_a_dog 4 points5 points  (2 children)

Can’t you just add to what’s there? Replacing seems wasteful.

[–]TakeMyPulse[S] 4 points5 points  (0 children)

I'll be using it somewhere else. So it won't go to waste. 😉

[–]dragos68 1 point2 points  (0 children)

Yes you can

[–]Sco0basTeVen 0 points1 point  (1 child)

You would probably need to make it a 2x6 wall to get the required r value. Unless spray foam can give you what you need.

[–]TakeMyPulse[S] 0 points1 point  (0 children)

Yeah, I'd actually prefer to make it 2x6. The foundation would allow for it as well.

[–]GoodGoodGoody 0 points1 point  (0 children)

Having trouble seeing how you arrived at 7. If those were 8” studs (unlikely) it would only be 5.7.

[–][deleted] 2 points3 points  (2 children)

Kind of related but just a stream of consciousness comment: my dad bought an FHA house before I was born. Like 45 years ago. $30,000 for 3 bedroom, one bath, about a third of an acre. Nice little place. He did some sweat equity and insulated it with friggin styrofoam. I will forever be jealous of the R value of that house. It’s otherworldly. I don’t have any experience, but I wonder if the spray-in foam insulation is similar.

The pink stuff is just punishment for everyone involved.

Edit: in case you are wondering, it was sheets of styrofoam. About two inches thick and whatever length and width. He kept a bunch of the remnants and put them in our biggest windows during the winter (and really hot summers), and I’ve just always been disappointed by houses since then.

[–]sedowaters 4 points5 points  (2 children)

You have to taste to fully determine its R value.

[–]TakeMyPulse[S] 6 points7 points  (1 child)

Tastes like itching.

[–]xX-JustSomeGuy-Xx 3 points4 points  (0 children)

Appears to be 220 calories per cup, or 920 joules.

[–]adamf514 1 point2 points  (0 children)

2 at the edges and 8 in the middle 😂

[–]Bright-Ad8496 1 point2 points  (17 children)

Batt insulation for 2x4 studs come in R 12, R 13 and R 14. The R 13 & 14 are fairly rigid compared to the R 12 being really flimsy and lack some thickness. I think yours is an R12.

[–]JudgmentMajestic2671 2 points3 points  (11 children)

I've never seen r12 or r14 in my life.

2x4 insulation is r11 (total garbage), r13 and r15 HD. R15 is dramatic better than r13.

[–]Bright-Ad8496 3 points4 points  (0 children)

In Canada, R12 was fairly common about 15 years ago but due to the Code changing to higher insulation values, it's not very common anymore but Home Depot and Lowe's still sell it for basement Reno's. R14 is common in new construction here.

[–]bkinstle 1 point2 points  (4 children)

Rockwool can get to R15 in that space. It's all I use now

[–]TakeMyPulse[S] 0 points1 point  (1 child)

Yeah I usually go Rockwool, but God damn was I shocked to see it's price jump from $56 (CAD) to $90 (CAD) in the last couple years. 😭

[–]bkinstle 0 points1 point  (0 children)

Dang! I bought a bunch last fall to insulate my new wood shop and I think it was about $600 for enough to do the exterior walls of a 18x14 building with 8.5" high walls.

[–]JudgmentMajestic2671 0 points1 point  (1 child)

So can High density fiberglass. I like both products but Rockwool is more expensive.

[–]bkinstle 0 points1 point  (0 children)

Best I can buy here in fiberglass is r12. But Rockwool is "less" itchy.

[–]streaksinthebowl -1 points0 points  (4 children)

It’s a common misconception but the relationship between r-value and heat loss is not linear.

For example, r2 to r5 moves you from 50% heat loss to 10% heat loss. r12 to r15 (same integer value difference) only moves you from something like 4% to 3%.

But marketing can still claim that’s 25% better!

[–]JudgmentMajestic2671 0 points1 point  (1 child)

Sure but that wasn't being discussed in my post. R11/R13 never fully expands in a friction fit cavity. R15 fiberglass does. That's why I think r11 is garbage.

I'd be surprised if real world installs of r13 passed r10 (not talking about the entire wall assembly, just the poorly filled cavity)

[–]streaksinthebowl 0 points1 point  (0 children)

Well that is indeed a different issue and a fair point, but also wasn’t at all clear in your post.

[–]Correct-Award8182 0 points1 point  (1 child)

The disparity is even worse than that. That's why whenever they add an extra inch or up the R-value, it is starting to make no sense. We're already in the range where an additional 4-5 is only adding fractions of a percent.

[–]streaksinthebowl 0 points1 point  (0 children)

Yeah exactly

[–]Expert-Parfait-7146 0 points1 point  (4 children)

Been a remodeling contractor for a long time. Never heard of or seen R12 or R14. At least not in the US. Standard size for 2x4 walls has always been R13, though as mentioned, nowadays, there is also R11 and R15. I'd bet that you have R13.

[–]Bright-Ad8496 1 point2 points  (2 children)

Retired home builder here, Yes we have R 13 in Canada and here are some links from HD Canada for R12 and R 14 which are common here.

https://www.homedepot.ca/product/owens-corning-r-12-pink-next-gen-fiberglas-insulation-15-inch-x-47-inch-x-3-5-inch-97-9-sq-ft-/1000406679

https://www.homedepot.ca/product/owens-corning-r-14-pink-next-gen-fiberglas-insulation-15-inch-x-47-inch-x-3-5-inch-78-3-sq-ft-/1000169644

[–]Potential-Captain648 1 point2 points  (0 children)

And R20 for 2x6 walls

[–]xXMapinguariXx 0 points1 point  (0 children)

Was an insulator and can confirm R12 was used for soundproofing.. R14 for any exterior 2x4 walls.. even did a job once where they used R7 for soundproofing a shared wall in a duplex, which was basically useless.

[–]LindsayOG 0 points1 point  (0 children)

R12 was the standard for 2x4 in Canada. Even though 13 and 13.5 and higher is sold now I always still math out my walls using r12 in my head for 2x4.

[–]lobstersnake -1 points0 points  (0 children)

R/itchy

[–]NotUniqueAtAIl 0 points1 point  (0 children)

It should say on it somewhere. Pull a piece out and look at the back. It's a faint number sometimes. Looks like spray painted on.

My opinion is this is an r11. If it's old enough it could be less but I am positive it is not more than r11

[–]dfieldhouse 0 points1 point  (0 children)

I don't know the R value but just looking at it ups my itch factor to 5.

[–]thefirstbric 0 points1 point  (0 children)

At least three

[–]fullgizzard 0 points1 point  (0 children)

R you sure you don’t want another blanket?

[–]Possible_Instance590 0 points1 point  (0 children)

Oh damn. This reminded me I have to put more of the devil's cotton candy in my attic. I am itching already.

[–]lolikamani 0 points1 point  (0 children)

You need a banana for scale

[–]ScotusDC 0 points1 point  (0 children)

Foam it green

[–]PestyThing 0 points1 point  (0 children)

Doesn't appear to be R-11, which fits in your standard 2x4 studded wall. Guessing those aren't 2x4's. Maybe 2x3's. R-value would be lower than R-11 in that case, if the batt fits, which it appears it does. Guess, R-8 or so.

[–]Inevitable_Moose2771 0 points1 point  (0 children)

13

[–]figsslave 0 points1 point  (0 children)

R-13 was the norm in 2x4 walls back then