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4 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.

In Mechanicals | Asked By Derek Roff | Jan 29 15
13 Answers

Does a flexible stainless steel chimney flue really need an insulation wrap?

I am preparing to install a stainless steel flexible liner inside an unlined masonry chimney on an exterior wall to provide draft for a wood stove. Every internet website selling the liners stresses the need for an insulation wrap to keep the vapors warm, improve the draft, and diminish creasote buildup. This has also been emphysized at GBA for similar reasons on multiple occasions. The available wrap liners are typically alkaline earth silicate (AES).

In General questions | Asked By W. Timothy Ward | Jan 26 15
0 Answers

Is power washing a 20 year old cypress siding house with a vinegar & water solution effective?

I am looking for ecological solutions to power wash the cypress siding on my 20 year old house. Using vinegar was suggested to me ~ has anyone had success with using vinegar, or can anyone suggest other ecological solutions?

In General questions | Asked By Shannon Dancy | 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.

In Green products and materials | 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.

In Energy efficiency and durability | 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.

In Building Code Questions | 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.

In General questions | 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).

In Green products and materials | Asked By D Wadsworth | Jan 28 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!

In Green products and materials | Asked By Apollo S | Jan 28 15
1 Answer

Workshop/garage — Unvented attic & insulation questions

I live in a mixed-dry area (Lubbock TX). Technically I am within Zone 3B but from a practical standpoint, I am right on the border of Zone 3B & 4B. We average about 18” of rain a year but it’s been much less in recent years.

In General questions | Asked By D C | Jan 28 15
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