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4 Answers

Insulating rim joist

I'm in the middle of finishing the basement. One wall has a half wall that's poured concrete and the other half is traditional framed. The other walls are poured concrete. The exterior has a r3 rigid foam sheathing and currently the rim joists are insulated with r10 fiberglass. My question is should I pull out the fiberglass and either use the cut and cobble method with r-10 rigid foam or spray foam or just leave the fiberglass in place. Thanks for the help in advance.

Asked By randall kingery | Mar 28 17
10 Answers

Dual-fuel high-efficiency natural gas / heat pump systems?

Does anyone have any experience with or thoughts on the hybrid "dual fuel" natural gas furnace systems that are combined with an air-sourced heat pump (instead of an AC only unit)?

The intent is for the heat pump to provide heat when its most efficient, but then switch to gas when the outside temperature drops to the point where the heat pump is no longer efficient or effective.

Asked By Jonathan Rich | Apr 21 13
6 Answers

Taping seams in plywood for health reasons?

Climate 4C. I am debating the cost and effort of taping our plywood sheathing.

Due to a few circumstances, we changed our building wrap to doubled-up 60-minute paper, attached to furring strips (closed rainscreen). Alternatively we are considering a hybrid product called Hydro-Tex, which is tar paper that has a drainage plane on the backside.

Asked By Mike Dominic | Mar 27 17
9 Answers

Insulation questions on a gut rehab

Hi all,

I'd like to comment on the usefulness of the website while conducting my research during our gut-rehab;we have been reading a ton of information about best practices during construction and what we should and should not do.

Some facts about the house:
Tri-level brick home in Chicago
2x4 walls
2x6 roof rafters
Roof pitch is 4:12
Forced air HVAC
Roof is 5 years old, one layer of asphalt shingles
Home built in 1965

Some facts about the project:

Asked By tkaj | Mar 28 17
2 Answers

To housewrap or not to housewrap?

Is housewrap plain and simple overkill?

Wall construction is 2x6 with dense-pack cellulose, OSB sheathing with joints taped (3M all purpose weatherstripping tape), covered by 2-1/2" of insulfoam Neopor EPS which is faced and joints taped (3M 8087).

The original plan was to housewrap at this point, add furring strips, then siding.

I'm wondering if there is any necessity for the housewrap over what is already a water resistive barrier.

Asked By Dave De C | Mar 28 17
3 Answers

Laminate floor underlayment in basement

I built up a basement floor with 3/4" OSB on 1.5" rigid foam over 6 mil poly on concrete slab (per this previous inquiry .http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/99205/insulation-basement-slab-question-polyethylene) .The difference this past winter was quite evident. Current question is what to use as underlay for laminate flooring. Some questions:
Should I use a permeable underlay so that the OSB is not encapsulated between the poly/foam layer below and an impervious "3 in 1" underlay above?
Or is conventional "3 in 1" underlay okay?

Asked By Grant Robinson | Mar 28 17
19 Answers

Low-slope "warm" roof build-up clarification

We are advancing on the planning stages of a new build project in climate 4C (near Vancouver, Canada). Thanks to the many articles and Q&As on this site I've got myself comfortable with most outstanding issues we are facing in developing our roof and wall build ups. This is a small building used as a holiday home, not fully occupied in Winter.
With that in mind any feedback from your good selves would be appreciated.
The roof is a mono pitch (shed style) front to back at just 1:12 with no "rafter" space to hold insulation
Build up:
- Exposed 3X8 Douglas fir beams

Asked By Quinn Sievewright | Mar 26 17
4 Answers

Critique this rough floorplan

We are in beginning stages of choosing an architect/project manager, but we have some wishes on how we want the floor plan to be.

Being amateurs, I'm sure there are mistakes. Please critique.

Our goals, wants and needs:

- make the house as small as possible, ut with enough room for everything we need/want
For example, we want a study, though that is not common practice here. We took that good practice from USA and like it a lot.

Asked By davor radman | Mar 28 17
7 Answers

ERV selection

I've been reading, reading and reading about the various ERV options. Once I think I've narrowed it down, I read a new article or a new model has be released. What is the latest thoughts on the ERV market ranking them from best and also value?

Asked By Seth Holmen | Mar 26 17
8 Answers

To vapor barrier or not to vapor barrier?

Hi all,

Pardon my ignorance or lack of proper nomenclature, but have a question regarding vapor barrier/retarder (I know they are not one and the same) and insulation.

Asked By jibba1 | Mar 28 17
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