Insulation retrofit questions

[Todd.Brock]

So as part of an on going home remodel, we are working on the outside of the house.

Our attic needs some blown in, the rim joist in basement is uninsulated , a cantilever in kitchen needs insulated , and the garage walls and attic are drywalled but uninsulated.


Found a retro foam company that fills the walls from exterior with foam by removing the siding and putting a hole in the sheathing. Because the garage walls are brick veneer, they fill between the brick and the sheathing- not the actual joist cavity. They wanted to use 3” of open cell on rim joist. And then r-38 blown in the attic spaces.

Our siding is getting done and I’m contemplating having the contractor rip off the ****** foam Celotex board , spray foam from the outside and then re sheathe and then put the new siding. What *****, is the siding is only on 3 sides of the second story. Rest of the house is brick. Hardly seems worth the extra expense at that point.


I found a guy to do r-38 blown in fiberglassfor .65 a sq ft. Each baffle is 3 bucks. I will probably do that for attic spaces, thinking about a DIY kit for the band board.

Has anyone had the pour in place retro foam done? I’m just not convinced between brick and exterior sheathing is the answer?

Thanks.

 

[yeldogt]

I have had a few houses retrofitted .. never with that foam. I have used lots of closed cell foam on remodels.

Does Ohio have any state programs for energy use audits? Some states have unbelievable programs and very good contractors. NJ has a clean energy program -- 5k in direct rebates and 10k 0% loan for 10 years .. they do audits and have to be certified. I had a combination -- done with closed and some blown product .. extremely happy. i looked into doing something in PA -- no program and really no one doing that kind of heavy retrofit work.

Success is really about the skill of the installer. I have seen very good blown in jobs -- and it looks less risky vs the open foam pour down the walls. Think I would ask if I could go see a job before committing.

 

[Todd.Brock]

Those are good questions. I will have to check on the audit programs for the state.

We are having insulated siding put on this week and thought it might make sense to have something done while the siding is off. They could fill three sides of the upstairs part of the house while the siding is being replaced vs having to remove pieces of siding That was just put on. I’m not convinced removing the bait gap between brick and sheathing is best idea, plus it’s about an inch thick. That’s a lot of effort for seeming a small amount of insulation. Wind block, yes- actual insulating value seems low

 

[mrramsey]

I got an estimate for a foam retrofit for my garage. Not worth it... I have two walls... roughly 423 sqft of wall area. Now subtract the overhead door, headers, two windows, and a man door and I am at 229 sqft of area that could be insulated. was close to $3k if i recall.
I can add some additional in the attic which I may do now that I am adding heat. The biggest improvement you can make is stopping the wind in my opinion.

What ever the number was it was substantial enough that I could have contracted with someone to tear out the drywall, insulate and re rock it for less.

 

[yeldogt]

Mine is a big brick cape -- with three stick additions (2 that I did w/ foam) and the typical 2nd floor full dormer towards the back. The basic structure was designed to leak as much as possible and have many small cavities with missing insulation. Brick part is block w/brick.

I took the ceiling down in the oldest addition and had the underside of the roof sheathing sprayed w/ closed cell foam. They closed up the attic (big but short height) with a combination of foam and blown in ... foamed the roof over the kitchen. Foamed any leaks they could get to and blew others. I took the HVAC out of the attic and replaced both systems. Like living in a different house -- 40k. The sealing and insulation was 7k. The state gave me 5k direct grant and 10k at 0% for 10 years. Cost was 25k -- I save the $88 bucks a month on energy for the loan.

 

[stm317]

Like living in a different house -- 40k. The state gave me 5k direct grant-- I save the $88 bucks a month on energy for the loan.

I sure hope it's nicer! You've got 35k in insulation there. At $88/month in savings, it would take over 33 years just to break even. I'm sure utility rates will increase over time, so your actual break even date will probably come a bit sooner than that. As I'm sure you didn't do it for financial reasons, but Thats a long time before the payoff.

 

[stm317]

Those are good questions. I will have to check on the audit programs for the state.

We are having insulated siding out on this week and thought it might make sense to have something done while the siding is off. They could fill three sides of the upstairs part of the house while the siding is being replaced vs having to remove pieces of siding That was just put on. I’m not convinced removing the bait gap between brick and sheathing is best idea, plus it’s about an inch thick. That’s a lot of effort for seeming a small amount of insulation. Wind block, yes- actual insulating value seems low

I think your approach is very reasonable. Do the three walls that you can easily get to while you can. Live in the house for awhile and see if you think it's worth doing that brick wall or not.

 

[38Chevy454]

Seems the biggest advantage for the foam is sealing air leaks. That is not insignificant and can make the feel of the room much better. Agree at approx 1 inch thickness of foam, it is not as good compared to filling the wall cavity with R-13 or R-19. Certainly a good time to take advantage with the siding being off and do what you can to improve the insulation. Kind of shocking how little insulation many of the older houses have once you get involved with it. Ceiling insulation is always good to put as much as you can reasonably do.

 

[Todd.Brock]

They are coming tonight for a full quote. I’ll see how it stacks up. I misquoted the process for brick veneer exterior walls. They said If they can get into the stud cavity then it will also be filled. Only time they fill air gap is on a block building with brick veneer

 

[PCustoms]

I had my house done last month, we didn't touch the walls though.

All closed cell:

4" on rim joist
2" on floor of attic, followed by 13" cellulose
1.5" on basment ceiling (garage) to seal the living area

$6500, and will be getting $1300 rebate any day now.

Most of your heat loss is going to be from the cantilever and the attic space.

My understanding is any retro insulation in the wall cavity is subject to hanging up on blocking, wires, itself etc. and is likely to leave gaps. Best bet is expose the wall and spray it.

Open cell is a waste of $ IMHO, doesn't get you any air sealing and isn't much better performance then the alternatives (i.e. dense pack cellulose )

 

[yeldogt]

I sure hope it's nicer! You've got 35k in insulation there. At $88/month in savings, it would take over 33 years just to break even. I'm sure utility rates will increase over time, so your actual break even date will probably come a bit sooner than that. As I'm sure you didn't do it for financial reasons, but Thats a long time before the payoff.

The insulation was 7k -- the rest was for replacing two HVAC systems. To get the grants you have to follow the energy audits and the contractors have to do blower door tests before and after.

My saving was estimated to be over 25% and I bought the better equipment to hit the full rebate. For many people with an old leaky house the cost for new equipment and upgrades is often around 20k. The loan and rebate is 15k .. so the homeowner is out 5k. The idea is to try and save the cost of the loan payment each month (10 years at 0% is $88/month)

 

[Dr Klaun]

They are coming tonight for a full quote. I’ll see how it stacks up. I misquoted the process for brick veneer exterior walls. They said If they can get into the stud cavity then it will also be filled. Only time they fill air gap is on a block building with brick veneer

Not good!!! The brick veneer, by nature, will let water into the assembly (like any masonry veneer) and needs that space to drain and weep the water out at the base. If this was filled, I can see mold and other issues (freeze / thaw) causing problems.

Insulation retrofits can be tough, as you most likely don't have a proper vapor barrier on the inside (warm side) of the stud assembly. Without this, the dew point will be within the center of the stud at the insulation, also causing moisture issues. Closed cell foam may provide the best solution, but moisture will always be around t hings that are hot/cold on each side. Tightening up the envelop in an older house will snow-ball fast if you want to do things right!

 

[Todd.Brock]

The price was about $6600 to retro foam the whole house, not the garage. He quoted about $3 bucks a sq ft of wall space. If I did just the three exterior walls for retrofoam, it was 5 bucks a sq ft ($4400)

Fiberglass for attic was quoted at 15 cents per inch , per sq ft. 3” of open cell spray foam for 120’ of rim joist was $1000

It was a little more than I expected. I think I am going to look at beefing up the attic with cellulose.