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Attic Insulation Recommendations? (photos)

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drw158

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We just bought a 1938 stone house (Nashville, TN), and I've been doing a lot of research on insulation. The house has a finished attic, and there is a knee wall on either side. There's also an attic hatch to access the ceiling above, with a broken gable fan.

They used regular batt insulation for the vertical sides, and for the ground they used this dark brown loose insulation. I can't tell what kind it is, the age, or if it's dirty. It's pretty compressed.

It looks like they did a pretty bad job of insulating. It's at least 10 degrees hotter upstairs! The knee wall doors and ceiling hatch are not insulated at all. There is a lot of missing vertical insulation on the walls. I can't tell if there is proper ventilation with the soffits. Nothing is air sealed that I can tell. The space above the ceiling looks pretty well covered, but it's not enough. I can see the wooden joists on the ground.

So my question is, do I throw all of this loose insulation away? It's gonna be tough trying to move that stuff around and air sealing it. I want to blow some cellulose in there. What would y'all do to improve the insulation of this second story?

Knee wall area:




Notice the brick chimney. Is that ok?



Above ceiling:



Image gallery with more photos: https://cloudup.com/cg6zlofbBEi
 
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nealtw

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The rafter that stops at the chimney should be looked at too.
The insulatiuon does look like blown in something or other, you may want to have to have it checked for asbestos before doing to much to it.
It woulbe nice to have soffet vents and box vents on the top but you also should have room above the sloped ceilng for insulation and air above that which would require some rework there. When you stand bats in the nee wall you just need to add some sccrapes of lumber to hold them in place.
 

drw158

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Thanks for the reply nealtw.

I know about soffit vents, but I'm not sure what you are talking about here:

It woulbe nice to have soffet vents and box vents on the top but you also should have room above the sloped ceilng for insulation and air above that which would require some rework there.
What about using foam board insulation sealed with spray foam for the knee walls (instead of using batt)?
 

drw158

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I had one more question to add:

When installing batt insulation in the knee walls, do I place the paper side out, or against the wall? If I install it with the paper side out, I'll be able to staple it to the framing and it will act as a barrier. I've heard it depends on the climate though, as it might cause moisture. I live in Nashville, TN.
 

nealtw

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I haven't seen paper backed for years. we wouldn't do here but that might be different where you are. So, I don't know.;)
 

drw158

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I haven't seen paper backed for years. we wouldn't do here but that might be different where you are. So, I don't know.;)
Interesting... It's all over my house and in all the how-to YouTube videos. What do you guys use instead of paperbacked batt insulation for knee walls?
 

Sparky617

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You want the vapor barrier (the paper backing) facing the conditioned space. You can install strapping across the studs to hold it in place. Neal is in Canada, I think they are pretty much using plastic sheeting and unfaced insulation there. You could go with R13 in the walls or go higher if you like and install 6" fiberglass. If you want to go foam, I'd just hire a pro to come in and do it instead of using foam board. Poly Iso sprayed foam has an R-factor of 8 per inch.

For the horizontal areas I'd probably use cellulose or loose fiberglass blown in to get everything up to the joist level and then lay unfaced fiberglass across the joists to raise the R value. You could do all blown in. You do want to install baffles to keep the insulation off the roof deck and install some soffit vents if you don't have them already.
 

nealtw

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Thanks for the reply nealtw.

I know about soffit vents, but I'm not sure what you are talking about here:



What about using foam board insulation sealed with spray foam for the knee walls (instead of using batt)?
The part of the roof on a slope between the knee wall and the top attic is a sloped ceiling in the room. In that area we make the ceiling thicker to allow for insulation and air flow.

And yes we use poly sheeting on the conditioned side of walls and ceilings and every join and nick and scratch is taped and sealed so there is no air leaks.
 

nunyabiz1

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While the spray foam is the best insulation by far it is also a complete ripoff with companies charging as usual as much as the market can possibly bear.
You can probably buy a new house for what it would cost to have this one spray foamed.

They have to be marking it up something like 1000%.

In an Attic, I personally want at least an R-60 I used Green Batting made from plastic bottles that I bought at Costco called Ecobatt. Was cheap and efficient and green. I think my total cost was like $120.

http://www.knaufinsulation.us/en/content/ecobatt-insulation

I put it over the old blown in 30-year-old insulation that used to be R38 but I am sure was now probably about R20, so I now have about R60.
made a big difference in how our upstairs rooms feel and lowered our AC bill.
 

love2xlr8

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Sorry for digging an old post from the grave, but how do you like this insulation ?.. I like the fact that is R-60 and green.. :)

While the spray foam is the best insulation by far it is also a complete ripoff with companies charging as usual as much as the market can possibly bear.
You can probably buy a new house for what it would cost to have this one spray foamed.

They have to be marking it up something like 1000%.

In an Attic, I personally want at least an R-60 I used Green Batting made from plastic bottles that I bought at Costco called Ecobatt. Was cheap and efficient and green. I think my total cost was like $120.

http://www.knaufinsulation.us/en/content/ecobatt-insulation

I put it over the old blown in 30-year-old insulation that used to be R38 but I am sure was now probably about R20, so I now have about R60.
made a big difference in how our upstairs rooms feel and lowered our AC bill.
 

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