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4 Answers

Multiple vapor barrier approaches in one house

I am building a small house in Southeast Alaska (mild, wet maritime climate). The walls will have R21 fiberglass batt insulation and 1 ½" of interior polyiso foam. The R-Max foam will also act as a vapor barrier.

In Energy efficiency and durability | Asked By Justin Smith | Jun 9 16
4 Answers

ROI for insulating 2nd floor walls

Hello GBA,

Fair warning that the answer to my question may be "as you wish" since there are very personal reasons for deciding one way or the other, but I am hoping for some advice that is able to balance the ideal and the practical.

In General questions | Asked By G S | Jun 9 16
2 Answers

Rigid foam over textured concrete basement wall?

I think the standard advice at GBA about insulating basement walls is to put rigid foam flush against the basement wall, and then install some sort of fire barrier, e.g. drywall. The key is to prevent moist air from contacting the cold basement walls and then condensing.

In Energy efficiency and durability | Asked By andrew c | Jun 9 16
1 Answer

Insulating catheral ceiling

Hi, I"m working on insulating an addition that is cold in the winter. It is an addition to the back of a standard rectangular ranch. One half of it is a covered patio, and the other half is a dining area. the dining area. The dining area has a cathedral ceiling, and a knee wall above a sliding door. The area above the covered patio is a vented attic. The knee wall in the dining area separates the dining area from the vented attic.

In Energy efficiency and durability | Asked By John Gifford | Jun 8 16
4 Answers

Plastic sheeting under concrete wall against existing foundation

So when i put up my addition, the addition's foundation is a full basement. It will therefore be somewhat below the height of my century home's existing basement. To prevent underpinning and generally expensive problems, we are installing a step in the foundation where it butts up against the existing wall. This way the wall is still supported, the addition can be the depth i want it to be, and I dont have to worry about the expense of underpinning. And i have a handy shelf once its done. :)

In General questions | Asked By Terry Sharpe | Jun 7 16
2 Answers

Can I install a minisplit heat pump away from the house?

We have been planning on installing a mini split in our small 1890's New England home we are energy retrofitting. But we are looking at some significant barriers to putting the heat pump on any of the sides of the house (set backs, DPW regulations on the width of the driveway, and future renovations on the other sides.) Can we put the minisplit on the side of a shed across the driveway and run the lines to the house underground? One contractors suggested this, but others are offering different reactions to its possibility. I am not sure what advice to take on how to go about this. Insights?

In General questions | Asked By Marie Brown | Jun 7 16
15 Answers

Tongue and groove mishap

So I installed my first row of T&G subfloor last night and screwed and glued it. What I didn't realize was that I installed it with the tongue side towards the rest of the floor.

Rather than rip up the first row I decided to try and pound it in on the tongue side which is not easy nor fun. The only problem I'm running int is that I am not able to get all the the T&G's to seat fully in the groove, instead they have the a 1/8" gap or so.

In Energy efficiency and durability | Asked By Mike M | Jun 6 16
3 Answers

R-30 Per Inch? Vacupor

I read online about a new product called Vacupor that claims R-30 per inch. Is this true?

In Green products and materials | Asked By Peter L | Jun 6 16
1 Answer

Looking for a product (like stucco) to cover 4" EPS foam on exterior wall

I'm nearing the end of the planning phase and have to choose a product to cover the exterior of my above grade conditioned crawlspace walls. The height of the crawlspace walls vary as the house sits on uneven granite. The rat slab is poured over the granite and some infill gravel and as a consequence is sloped and uneven.
The walls are a mix of wood framed (2x6) and concrete (8") on a walkout design. (wood is all above grade).

In Green products and materials | Asked By tim brown | Jun 6 16
10 Answers

Venting for kitchen, bath, electric clothes dryer — duct paths?

The bath and laundry are on the second floor. The master bath can go to the rear exterior wall. What about the other bath? Would a vent hood look out of place on the long side (front) of the house? Siding will be white Hardie lap siding.

Or would you run it through the framing to the back exterior wall (20 ft.)?

How about the clothes dryer?

How about the kitchen? Better to go straight up through the metal roof or to the exterior wall?

Would the vent around the white siding be a issue?

Thanks so much for this site.

In Mechanicals | Asked By Quinton Bryant | Jun 3 16
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