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8 Answers

Attic insulation reality check

It's time to get my attic air sealed and re-insulated and I've committed to hiring it out since the 6/12 pitch truss attic is a horrible place that I hate to work in. I'm having trouble finding people willing to blow cellulose. Everyone around here seems to want to blow fiberglass. Is this a major issue?

The first bid I've gotten is $3.20/sf for attic floor air sealing and R-30 worth of blown fiberglass. Sane/insane?

Asked By Nathaniel G | Mar 26 15
4 Answers

Old house, wet brick

The picture pretty much says it all. We had terrible ice damming this year, as did just about everyone in my area; houses both old and new saw wet walls and rainy windows for the first time ever. My house was built in 1850, and I have to imagine this has been a problem before. But this was our first full winter here. I'll try to explain the situation as best I can:

Asked By Chris Ermides | Mar 26 15
1 Answer

XPS as interior insulation on a plank wall

Architect's plan calls for 2" of "rigid" on interior side of a plank wall in Williamstown Ma (zone 5). Even if we tape the seams and air seal as best as possible, I am still concerned that moist air will get to the back of the planks and create moisture issues. The exterior is not being touched and I assume that there is no kind of air space between the planks and the siding. The space will be air conditioned in the summers and the 2" of xps (class II vapor retarder) gives me some drying capacity to the inside. Is that enough? How risky is the assembly?

Asked By Joseph Carry | Mar 27 15
11 Answers

Non-typical insulation of barn / garage

I live in Interior Alaska Zone 7/8. I have a rather large barn pole barn that needs to be insulated so it can be heated. Since it is rural there is no code but i want to ensure that i do not do something that damages or ruins the building over the long term with that said money is not unlimited. The space is intended to be heated to just above freezing 35 to 40 typical with the ability to warm even more during use. Not a business just personal use during the week.

Barn size is 50x60 with 14 foot walls.

Asked By James Williamson | Mar 22 15
10 Answers

Insulating scissor truss

Hi, I am building my first house, what a project that has turned out to be but that's for another day. Anyways, our great room has scissor trusses for a nice pitched ceiling. I would like to have at least 24" of insulation to keep things nice and toasty in the winter. There is a 4' overhang outside on either end. I nailed a 24" high plywood leaving a vent space above where the red is on the layout. My question is what material and how to go about it. To use the high density cellulose is has to be contained by some mesh? Any input appreciated.

Asked By Tom Smith | Jul 19 14
4 Answers

Insulating truss joists 16" on center — Best way?

Batt insulation for 24" o.c. The 2x lumber is 23" wide. The truss joists I'm looking at are 2x4 lumber 24" o.c. The space between the trusses is 21.5". Does anyone know if R-19 batts are available in 21.5 or 22"? Seems like squeezing a 23" wide batt will not work well.

Also the tiger wires used on 2x lumber will not work well on a truss. Is there another method of holding the batts up to the floor?

Asked By Walter Gayeski | Mar 25 15
7 Answers

Evaluating feasibility of solar panels in site rated at 895 (or 65% TSRF)

Just got a quote from solar panel install company and thinking I may skip solar and redirect funds to doing more insulation work on the house. But before I do that, I wanted to run some thoughts by here.

1. I am calculating that per kW I will be at $4.25 installed (I am in Boston area). Considering article I just saw today on GBA pegging average installed price $0.80 less per kW I am discouraged.

Asked By Apollo S | Mar 25 15
1 Answer

Improving panned return ducts

Our bungalow is a standard setup, with a 2 story addition added later. In the whole house, best I can tell, there are 3 return ducts, all on outside walls of the original house (1 is now interior), all on the 1st floor and all panned. I can access some of them from the basement.

The 2 farthest from the furnace are panned across to the center of the house, then in a duct going below the joists, then back into a panned duct that goes above the duct pushing air out, and then into another duct that goes back to the furnace, if that makes sense.

Asked By Jeremy M | Mar 25 15
6 Answers

A different use for earth tubes or pipes

I have been intrigued for a while by the potential of Earth Tubes (most significantly discussed here at: http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/my-earth-tube-story'rel="My Earth Tube Story"'. I have a project coming up that will involve regrading, earth fill, and irrigation installation on a sloped half acre, so I may have the opportunity to bury some pipe (4-6ft deep, climate zone on the line of 5/6), if it seems worthwhile.

Asked By Stuart Miller | Mar 23 15
6 Answers

Small addition

I am in the early design phase of a small (12'x20') addition for a client in climate zone 5 and am just looking for suggestions as to the best new construction insulation & air sealing details to use.

It will be wood frame construction with a crawl space and a gable roof with vaulted ceilings inside.

I am leaning toward the zip wall sheathing system on walls & roof deck with a rainscreen on top and fiberglass batts in the 2x6 stud bay. Is the zip wall roof sheathing of sufficient thickness to allow me to build an unvented roof without having to spray 2-part foam on the underside?

Asked By Jason Schatz | Mar 24 15
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