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1 Answer

4 Insulation questions

Greetings, I am finishing my gutted basement, and had a few insulation questions. I live in Portland, OR (zone 4).

General information:
My foundation is poured concrete, 4 feet underground with slab floor. The basement walls therefore consist of concrete (lower half), and 2x6 stud wall (upper half). Stud walls have exterior sheathing, house wrap, hardiboard siding. On the interior, there will be 1/2 inch plywood (earthquake retrofit) between the studs and drywall. My house was built in 1967.

Question 1:

In General questions | Asked By Matt Draper | Feb 13 17
1 Answer

Mini-splits in a split-level home? (Zone 4)

Hi all,

Thanks to all GBA contributors for the info on this site, and to Dana Dorsett for the technical guidance on many related topics from another forum. I became a first-time homeowner last fall. Your contributions got me started in the right direction on my HVAC replacement project.

In General questions | Asked By Jerry C | Feb 13 17
3 Answers

Metal vs tile roof, with price parity?

I live in Central Europe, where, for the most part, tile roofs are by the most used roofing system.

Currently, I am trying to do some cost cutting on my future home, so I started investigating metal roofing. Looks really great.

But where I live, it's not any cheaper than tile.

House is brick, mortar and concrete, and roof itself would not be insulated, only the ceiling.

Should i keep investigating metal roofing, or just go with tile in this case?

Also, while I'm at it, is it worth giving any thought to flat roof, when low energy houses are concerned?

In General questions | Asked By davor radman | Feb 13 17
3 Answers

Open-cell spray foam for field stone basement wall?

I am finishing a basement in a old home (1850s) in NE PA. Can open cell spray foam be applied to an interior field stone basement foundation wall if the wall has had a vapor barrier such and Grace ice and water shield attached to it? I ask because open cell for one is much cheaper than closed cell and does not have the off gassing and harmful blowing agents that closed cell does. Closed cell however is vapor permeable. I must put in the grace shield due to the small amount of moisture that does weep from two of the foundation walls.

In General questions | Asked By Ben Hardy | Feb 10 17
4 Answers

Insulating diagonal hardwood sheathing in climate zone 3 - insulated lap siding + drainwrap?

My wife and I are completely renovating my great grandparents' house in central Mississippi, and we will soon replace the siding, much of which is in bad condition. As we have looked at options, the insulated Hardie lap siding has been one recommendation, with the idea being that Tyvek drain wrap would go between the back of the siding and the beautiful diagonal sheathing.

In GBA Pro help | Asked By Joel Fyke | Feb 12 17
3 Answers

Kneewall insulation planning stage - Thoughts appreciated

Hi All,

I have read all the available articles and Q&A on kneewall insulation, including Dana's comments on playing the fool on multiple occasions and therefore would appreciate your views on my situation / questions / possible approach.


- Climate Zone 5 (Chicago area)
- Walk-in closet over attached 2-car garage (20ft x 8ft space)
- Garage attic has soffit and ridge venting and this attic is isolated from the rest of the home's attic space, except for one HVAC duct which comes from the "main" attic. This duct runs above approximately half of the kneewall ceiling

In Energy efficiency and durability | Asked By Joe Duchek | Feb 10 17
1 Answer

Balloon Frame Basement Air Sealing and Insulation


I have a 1906 balloon-frame house in Essex County, NJ (Zone 4A, borders 5A). My unfinished basement is quite cold, which makes first floor cold as well.

In Green building techniques | Asked By Robert Howell | Feb 11 17
7 Answers

Absolute Steel hybrid wood stove

After much consideration I think I've found my wood stove. I saw a National Geographic program on the Wood Stove Decathlon 2013 where this stoves larger cousin (the Ideal Steel Hybrid Wood Stove) won the grand prize.

I need a smaller stove so the Absolute model seems perfect to me. I also like the fact that the EPA emissions are listed as being only 0.5 grams/hour and it has an efficiency of 77%. Has anyone used one of these stoves already?


In Green products and materials | Asked By Scott Wilson | Feb 7 17
1 Answer

Converted Porch Crawl Space Sealing and Insulation


I have a second question about my 1906 house in Essex County, NJ (Zone 4A, borders 5A).

At some point, the 7' by 15' back porch was converted to a bathroom and mudroom. The walls and ceiling/roof appear to have been insulated with fiberglass batts, but the floor/foundation was not insulated.

In Green building techniques | Asked By Robert Howell | Feb 11 17
6 Answers

SIP roof with roofing sleepers

I want to create an air space between the SIP roof panels and the finished roof. I am taping the SIP roof seams with SIGA tape and installing a breathable roof membrane (Majcoat).

I want to create an air gap between the finished metal roof and the SIP. I was planing to use 2x's but the problem is which way to run the boards?

In GBA Pro help | Asked By Peter L | Feb 10 17
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