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0 Answers

Insulation help for attic garage in Zone 8b (while allowing for storage)

Hi all,

Long-time reader of GBA, very infrequent poster --- amazing resource here. Thanks to all who contribute.

Looking for input and advice on insulating my garage as part of a conversion into conditioned space for use as a workshop (no longer parking there, so very infrequent raising/lowering of garage door). Just installed high-efficiency (SEER 26) 1-ton ductless mini-split as HVAC (predominantly cooling, of course, but with heat pump for couple of winter months).

Asked By CJ Fox | Mar 29 17
0 Answers

Green & Passive design

As an architectural designer, I have long been interested in green and passive home design, having dabbled and dreamed. I now have a project that will encompass both, as well as the use of SIPs for roof and walls.
Simple questions with elusive answers:
1. Where can I find the angles of the sun at June 21 & Dec. 21 for a specific latitude?
2. How do a loft area and high vaulted ceilings fit in? It seems that both the Window to Wall ratios, and mechanical load numbers are all calculated using square footage. Surely ceiling height and volume have an impact.

Asked By Becky Nemetchek | Mar 29 17
6 Answers

Ideas for this floorplan Pt. II

....and I'm back! The system wouldn't let me reply to my own thread. It kept marking my reply as spam.

It's been a while since I posted an update to my thread but here it is.

I have processed all of the feedback given to me and applied this to my original wants. The idea is an open plan, living areas to the south, concentrate plumbing in one area, large master with walk-in shower, tub, master bed with walk-in closet, large kitchen, et cetera and this is where I am. I moved the master closet back up to the north wall again and I've added lots of other closet spaces.

Asked By Drew Baden | Dec 14 16
5 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
2 Answers

Insulation Question

First of all, great site. I wish I would have found this sooner.

I'm doing a home addition in region 4 (Northern Virginia). The house is about 70 years old. I'm pretty clear on insulating most of the house. We're using the Zip r-5 product on the exterior, sprayed cellulose inside the walls, and blown cellulose in the attic. Also, I plan to do the rim joists with open cell spray foam.

There are three tricky areas I can't figure out.

Asked By GregKu | Mar 29 17
12 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
5 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
20 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

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
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
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