Community: Energy efficiency and durability

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7 Answers

Conditioned attic roof detail

I am in the process of fine tuning the details of a one and a half story house I would like to build next year. It will be in Northern New York on the border of the 5A and 6A climate zones The upstairs has a knee wall and a couple access doors to the attic space. I think I have decided to just run the zip-system up the walls and around the top of the roof rafters to simplify the air sealing.

Asked By Dillon Vautrin | Jul 23 14

2 Answers

Open-cell vs. closed-cell

Thanks Mr. Holladay for responding to my question however I don't think I was clear with my question. I wanted to remove the floor installation it my atic and replace it with foam installation between the rafters. I've heard many different things about open & close cell that I didn't know what was true or false. What is recommended for the atic ceiling, open or closed cell. What is R value and what number should I try to accomplish with the R value.

Asked By TERRY KELLEY | Jul 23 14

1 Answer

I have a roofing / deep energy retrofit question

I have a roofing / deep energy retrofit question. I'm just beginning a deep energy retrofit as a retirement home on a permaculture garden-farm project in northern Alberta, Canada (ASHRAE Zone 8). Tomorrow we are moving a 42’x28’ bungalow 200 km.

As it needs a new roof (old shingles are stripped to sheathing and house tarped at old site), the current plan is to chainsaw the eaves, then apply air/vapour barrier, insulation (either Roxul ComfortBoard or EPS) to exterior walls, preserving as much interior space as possible.

Asked By Janet Blayone | Jul 22 14

1 Answer

On chosing spray foam installation for the attic

Which type of spray foam is recommended, open or closed-cell?

I'm about to remove my blown-in insulation out of the attic, and I was trying to figure out which product is recommended -- the open or the closed-cell?

Asked By TERRY KELLEY | Jul 22 14

3 Answers

Using rigid insulation correctly

For zone 6, when building a new construction wall assembly, why wouldn't this method work well- starting from the exterior side- OSB sheathing, Roxul R-23 cavity insulation, 1-2" foil-faced polyiso rigid board placed continuously over inside of wall, joints taped appropriately, furring strip, drywall. It seems that this would pose the least risk-as the continuous foil-faced polyiso will stop to a great extent vapor transmission. I realize that no assembly is completely vapor leak proof, but the OSB can dry to the outside if need be.

Asked By Peter Nadler | Jul 22 14

3 Answers

Has the Oak Ridge study on convective heat loss in blown fiberglass been updated to cover newer materials?

I'm evaluating blown cellulose vs. blown fiberglass (Knauf Ecofill). The Oak Ridge study is often quoted regarding the drop in R-value of blown fiberglass when the temperature differential is high. However the tested fiberglass density (.4 - 5 lb/ft^3) is much lower than the newer fiberglass.

Asked By Neil Weinstock | Jul 21 14

3 Answers

Evaporative Cooler vs Mini-split

I'm in the planning stages of a remodel and need to make a decision about cooling.

Asked By Eric West | Jul 21 14

2 Answers

Are there cooling benefits for installing an exhaust fan in a false ceiling?

Hello,

I so wanted an energy efficient home. I specified that when we began the remodel. All of the new windows are energy efficient, as are all of the appliances, and I am thankful for that.

But to my disgust, the insulation that I requested for my remodel was not installed and the walls are up. My home is a penthouse in a 1970s brick building in Barcelona. It is on the 9th floor, and has no common walls. 3 sides (north, east and south) are fully exposed. The west wall is partially exposed and has minimal protection because about 75% of it faces an light well.

Asked By Gary Oliver | Jul 20 14

5 Answers

Suggestions for insulating a large garage workshop

Hi everyone. I just purchased a property in western Massachusetts zone five a. I am planning to renovate the existing 24 x 60 barn for use as a year-round workshop. The building is slab on grade with 2 x 6 framed walls 24 inches on center, sided with rough pine board and batten nailed to the studs and bracing. Currently, there is a bit of air exchange between the interior and exterior due to some of the battens pulling away from the nailers.

Asked By Benjamin Jones | Jul 18 14

3 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

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