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3 Answers

Rigid foam around SIPs in climate zone 4a?

I've been a passive (not pun intended) participant of these boards and this site for a while. It seems hard to catch up on it all, so hopefully my question here isn't terrible :)

I'm thinking of scraping my house off the land and building new. My goal is zero net energy. I've extensively remodeled one home including an addition myself, but I'm no professional. I do want to build and subcontract most of this home myself as well. I'm just an avid building science lover and construction enthusiast.

In Green building techniques | Asked By Michael Bender | Jul 15 16
1 Answer

Should I connect radon vent to the airtight basin lid?

I recently installed a sump basin with an airtight lid connected to interior & exterior drain tile with the intention of using it to vent radon also.

The plumbing inspector told me that I could not vent off of the basin, and that I would have to install a vertical pipe off of the interior drain tile. (could even be directly adjacent to the sump basin)

The reasoning being that in order to service the sump pump, that the radon line would need to be disconnected to remove the cover, and this vent line may not get reconnected.

In General questions | Asked By Adam Peterson | Jul 15 16
4 Answers

How can I add insulation to an insulation-board sheathed building?

We recently purchased a pre-built 12 X 24 shed. It has unfinished interior walls 2X4 stud 16"oc, exteriorly sheathed in insulation board foil-faced on the interior, painted wood siding covering the insulation board. The ceiling is sheathed in LP Tech Shield radiant barrier.

We had the previous owner/builder add a simple interior wall to divide the space into two approximately 12X12 spaces. We intend one side for gardening equipment. The other side is to perform as an art studio.

In Energy efficiency and durability | Asked By Barbara Robertson | Jul 14 16
3 Answers

Insulation Issue: Renovating EPDM low slope cathedral ceiling with flash and batt and venting problems

After researching GBA to death, I have come to the conclusion I need to ask the experts. Forgive the novel but I’d rather explain in as much detail as I can.

I am in the midst of an addition/renovation project and have hit a major snag with the roof/ceiling. I’m never going to achieve GBA nirvana, but ‘good enough’ is better than what I had. My grandfather built the house in the 1960’s and it was recently willed to me, but it’s time for changes. Kudos to my grandfather for building a freakishly strong house, but not a well insulated one.

In GBA Pro help | Asked By Robert I | Jul 15 16
9 Answers

Are sealed electrical boxes needed for the airtight drywall approach when using drywall gaskets?

I'm planning to use the airtight drywall approach to air-sealing in a single room renovation.

As I understand it with internal walls the concern is penetration into the attic. So I'm using drywall gaskets from Conservation Technology to seal the drywall at the top (and bottom plates). If the top-plates are well sealed do I need to worry about air-sealing the electrical boxes? Warm air could penetrate but not rise into the attic (or more likely in Zone 2) warm air won't ever get from the attic behind the drywall to enter the room.

In Green building techniques | Asked By James Howison | Jul 20 12
2 Answers

Near zero / passive home builders in mid-west Georgia?

I am ready to initiate process to design-build or retrofit to passive house standards in Muscogee county, GA or Lee county, AL. Having trouble locating experienced near zero / passive house builder outside of Atlanta, any ideas?

In GBA Pro help | Asked By David Floyd | Jul 15 16
1 Answer

I'll be giving a presentation at the SolarFest gathering today

Anyone living near Manchester, Vermont, may be interested in checking out this weekend's SolarFest gathering -- a combination of live music and workshops on solar energy and sustainable design.

At 6:00 p.m. tonight (Friday July 15), I'll be giving a presentation at SolarFest on passive solar design.

For more information, see these web sites:

SolarFest Workshop Schedule

SolarFest General Information

In General questions | Asked By Martin Holladay, GBA Advisor | Jul 15 16
32 Answers

Desperate help, minisplit sizing

I'm a GC building my own home. I live in an extremely rural area with very few knowledgeable hvac professionals within 300 miles. I have decided to go with mitsubishi ductless mini splits to heat and cool the entire house. Basically I need help choosing what size units to purchase, how many heads, and to me most importantly where to place the units. This home will be occupied by just me and the wife so interior doors will be open most of the time.

In Mechanicals | Asked By aaron miiller | Jul 13 16
4 Answers

Best way to install a single-pane stationary window in a shower?

We are doing a complete bathroom remodel. My wife wants a window in the new 36' x 72" walk-in shower. It will look into another room with a view to the outside. The "window" could just be a single 3/8" pane of tempered glass. ideally, it would be flush with the shower side of the tile wall. I'm looking for the best way to frame the wall, install and waterproof the "window". Window opening would be approximately 36" wide and 48" tall, starting at 48" from floor of shower. Tile will be floor to ceiling in shower. Ceiling at 8'.

In General questions | Asked By Jim Gruenewald | Jul 14 16
2 Answers

Insulating ceiling under a deck

Climate Zone 5

We have opened up the ceiling of a small section of a kitchen that is under a roof deck with membrane roofing. This is in a 1910 house that has NO insulation in the walls. There is currently no insulation in this 2x8 framed ceiling cavity. There are recessed down-lights. (The main roof of the house is receiving new R60 blown in)

Back to the little section of ceiling under the deck.

The insulation subcontractor wants to install 2" closed cell spray foam and 5 1/4" BIBS. I worry about the double vapor barrier around the deck sub floor.

In Energy efficiency and durability | Asked By Meri Lewis | Jul 14 16
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