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2 Answers

Insulating old Victorian

Good day,

First, thank you for providing this service as it is appreciated. Second, I saw a recent post on insulating old Victorians and it applies to me also.

Background: 1888, double, 5000sq ft Victorian in Columbus, Ohio. All 40 windows are bad and replacing this Spring. Insulation is non existent or questionable.

One of many issues: Insulation: On one side the past owner built a 6-8 inch interior sheetrock wall around the outer walls. There are some unfinished rooms which I can see dirt insulation in between, but still unsure of the entire area.

In General questions | Asked By Loren S | Jan 30 16
5 Answers

I'm adding 1 1/2 formular foam to outside of 2x4 wall. Is there a ledger strip to protect the edge of the foam and also allow for 3/4 rainscreen ventilation?

It would be nice to have a product that would protect the edge of foam and then transition to insect screen for the rainscreen 3/4 inch. And then it would be great if it was available with a a vinyl siding start strip built in also! I may be asking for a lot, I know but is there such a product? Thanks, Dave Green

In Energy efficiency and durability | Asked By Dave Green | Feb 1 16
11 Answers

Larsen truss with veranda (roof and deck)

So I'm considering the Larsen truss for my addition. 2x4 load bearing walls on 16" centers, 1/2" plywood on top for shear, poly on that for vapour barrier, followed by about 8-12" of Larsen truss cantilevered out from the foundation (2x2/2x3 inside with plywood spacer to 2x2/2x3 on the outside), then 1/2" plywood and wooden siding. Roxul batt inside (for easy utilities) with blown in cellulose on the outside.

In Green building techniques | Asked By Terry Sharpe | Jan 12 16
6 Answers

Should I fix these attic vent baffles?

My builder recently added the attic vent baffles to my house under construction. I looked at them and realized that when I had read about attic vent baffles on Green Building Advisor, these don't follow the recommendations and I'm looking for opinions on how much impact this will have and if I should have them make a modification.

Right now there is no ceiling drywall or insulation up there, so it would be "easy" to make a change, but in a week we hope to have ceiling drywall and insulation blown, so then it would become too late.

In General questions | Asked By Nick Hall | Jan 26 16
7 Answers

Innie or outie windows with exterior foam?

CZ 7 Northern MN, 2x6 standard frame with 4" exterior foam. Exterior foam is basically unknown here. My builder and the local lumber yard person think I should go with innies, because they both feel the windows would get too cold being on the outside of the wall. My windows will be Marvin double hung, fiberglass or aluminum out, wood in. I had thought I would go with outside windows because I thought it would be easier (cheaper) to extend the frame inside, than extend the trim outside, but I am not stuck on either one. Thoughts and comments appreciated.

In Energy efficiency and durability | Asked By Steve Vigoren | Jan 31 16
5 Answers

Fixing Basement Insulation

We recently purchased a newer home in zone 5.5. The unfinished basement is insulated with fiberglass batts framed between 2x4 spaced 24" apart. It has poly vapor barrier against the concrete, then it looks like R-19 unfaced batts, then another layer of poly vapor. The studs are spaced about 1" away from the poured concrete walls. I was thinking of removing the vapor barriers and batts and insulating between the studs with 3" XPS foam. The question is how best to do that?

In General questions | Asked By Mel Tillyard | Jan 31 16
0 Answers

Slab Floor Construction

I was a watching a video today of a slab on grade construction at a new build PH in Ireland. Their buildup was radon barrier, concrete, and then what appeared to be 2 layers of 4" thick polyiso-like sheets. The sheets were to be taped into aerated concrete blocks around the perimeter to maintain the thermal envelope. Seems as if in the US, the insulation layer is usually underneath the concrete. I know in a retro you can put foam on top of concrete, but anyone know why is it not typically done this way in new PH builds here, especially if you don't want a finished concrete basement floor?

In PassivHaus | Asked By Jonathan Lawrence | Feb 1 16
4 Answers

Removed AC'ing of garage...now I understand why it was there to begin with...

Hello - I put 3 months of effort into refurbishing the garage. i own a 2 story house where the the ceiling of the garage is the floor of the 2d story - that is, there are two bedrooms and a hallway directly above the garage.

Although there were a myriad of issues in the garage space, it was noted on the inspection report (I bought the house 2 years ago) that there were air intakes in the garage and this is obviously a bad idea (car exhaust, other fumes, etc). I also discovered that there were ducts leading into the garage AC'ing the garage. Odd, since the garage leaks like a sieve.

In General questions | Asked By daniel slaman | Jan 31 16
12 Answers

New roof, new skylights, new condensation... and not a lot of answers. Any help?

Hey everyone. I don't normally post to anything but I'm at the end of my rope and not sure which experts I can trust so looking for some extra opinions before I go and do nothing or start making tons of holes in my roof.

In GBA Pro help | Asked By S. B. | Jan 24 16
18 Answers

Would a $5,000 investment in rooftop solar make economic sense?

I'm building an all-electric home. I am currently paying 7.22 cents per KWH. I'm poor, but could possibly budget $5,000 for solar power, if 30% of that $5,000 is returned to me as a tax credit. Would investing that $5,000 in solar power make sense? (This question is premised on the cost to me, after the tax rebate, being $3,500.) Or, would my $5,000 be eaten up by installation costs, and leave me generating enough electricity to operate an LED light fixture? It doesn't matter what I could do for $15,000 or $20,000.

In General questions | Asked By James Timmerberg | Jan 29 16
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