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5 Answers

Unvented roof deck with dense-packed cellulose -- vapor barrier?

Hi I just dense packed my attic ceiling (it is a livable space, not crawl) with dense pack cellulose (8"), held in with insulweb. we put the cellulose right up against the roof deck. I am concerned whether I need a vapor barrier and where it should go. My plan was to just put rough cut wood (not tongue and groove ontop of it for the ceiling, but a few people who looked at it thought I might need a vapor or air barrier. The roof is not vented.

Asked By carrie da | Jan 29 15
5 Answers

Roxul Comfort Board vs. Thermafiber RainBarrier

Any differences I should be aware of before I choose? I am wanting to use mineral wool for exterior insulation on a wood frame, two-story dwelling. Very impressed with Roxul online information, technical specs etc. Can't find much about RainBarrier, other than the company info sheet, but it's 1/2 the price of the Roxul. Thermafiber says that the Rainbarrier HD is the product they have made to be comparable to Comfort Board, but cannot find any comparisons between the two.

Asked By Caitanya Joy | Jan 23 15
8 Answers

Ductless minisplit retrofit question

I live in southeastern NC, near the coast. My house is just under 1900 sqft with a bonus room over an attached two car garage. My HVAC ducts are in the unconditioned, vented attic. I understand the problems with this. Would a ductless minisplit make sense as a retrofit option? If so, can you just remove the ductwork and patch the drywall where the supply registers are? How do you determine how many head units you need and the best places to install them? I was thinking about this as an option for when I eventually have to replace my heat pump and/or air handler.

Asked By Jason Dennis | Jan 12 15
1 Answer

I will not be able to finish my deck for months but would like to get a final inspection signed off.

Suggestions for temporary deck railing that will meet code would be much appreciated. We are in Washington State.

Asked By Jacque Hyler | Jan 29 15
3 Answers

Any ideas on best/greenest counter top materials?

Cost per square foot, if available, would be appreciated.

Asked By Jacque Hyler | Jan 29 15
4 Answers

Waterproofing exterior of basement wall with spray foam

Hi, Recently, I had a problem, my basement wall was bowing in. A company came out and used hydraulic jacks and straightened the wall out. They dug out the exterior and supposedly sprayed a foam on the outside to waterproof. My walls now leak horribly when they did not leak at all prior to their work. They said they could not put a bladder on the exterior because the walls were the old stacked limestone so they used the foam which they said would do the same thing the bladder would.. I called them and now they are saying the foam is not a waterproofer.

Asked By Josa Combs | Jan 29 15
3 Answers

Yet another window question (YAWQ): Pella Impervia feedback?

Hello,

I'm building a house in central Oregon (zone 5). It's a mostly passive solar design, with CMU shell construction that is insulated on the outside (my builder has a patented method to attach insulation to exterior of CMU walls) and this plus a mix of tile and concrete floors means I have a huge amount of thermal mass.

So we're considering using Pella Impervia with their high SHGC "Natural Sun" glazing for five of the main south-facing 42" x 112" windows (Alpen and their better U-value is planned for the other 30+ windows).

Asked By D Wadsworth | Jan 28 15
2 Answers

Combining electric cove heaters with PV

In a recent blog, Designing an HVAC System for a Cold Climate, Malcolm Taylor is quoted as recommending electric cove heaters, and a link to the Comfort Cove line from Radiants Systems, Inc. is provided in the blog text. Searching Green Building Advisor turns up half a dozen other references to cove heaters, all very short, and all positive. I wonder if there is more useful advice on choosing and using this technology for supplemental heat.

Asked By Derek Roff | Jan 29 15
2 Answers

Adhesive and ignition barrier for unfaced polyiso?

I got couple pallets of polyiso from an insulation recycler. It is NRG Insulation, 1.5" stuff. But it isn't foil-faced. Will be installing those in my basement with poured concrete walls.

Two questions:

1. What is the best adhesive (I can hopefully get at Home Depot or Amazon) to glue those polyiso panels to the basement wall, and how much of it do I use per panel?

2. Since it is not foil-faced polyiso, can I use FSK paper for an ignition barrier or is there another alternative, besides drywall?

Thanks!

Asked By Apollo S | Jan 28 15
17 Answers

Double Staggered-Stud Wall vs. 2x3 + Foam Strip + 2x4 Wall

My new house will be in a part of climate zone 2B in Arizona where the winter nights often dip into the 30s and the summer days often rise to 100 with around 45 days of "monsoon season" mostly in August when we'll get an hour of thunderstorms once or twice a week. We have moderate to severe termites.

Asked By Jeff Cooper | Jan 23 15
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