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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
3 Answers

Will I have to be concerned with pipes freezing when I install a Mitsubishi Hyper heat system?

I have oil heat with forced hot water presently in my home in NH. The house is 5 years old and very well insulated. I want to add the Mitsubishi hyper heat to our house. It will have two indoor units one on each floor of our home. We are not putting a unit in the basement. It is primarily for cooling, but would like to use it to maintain the home at 55 degrees when we are not there. This is a vacation home so we are there mostly on weekends. My concern is that the oil burner will only be running to maintain hot water. We have a tankless unit off the boiler.

In Mechanicals | Asked By Rob Murray | Jul 14 16
30 Answers

Siding Recommendations


I am trying to find a green, vertical tongue and groove, or ship lap style siding, that is low maintenance or maintenance free. I am trying to achieve an unfinished or lightly stained real wood grain look. Most of the products I have seen are solid colors, which I am trying to avoid. Thanks in advance for any recommendations!


In General questions | Asked By Chad Kotlarz | Jul 10 16
2 Answers

Floor over slab insulation?

I live in Pittsburgh, PA. I'm turning an existing porch into a dinning room. There is an existing 6" slab with 1 1/2" thick pavers over it. The pavers are cemented to the slab and grouted. Dirt under the slab.

The local code calls for R10 insulation 2' in around the perimeter walls. I wanted the entire floor insulated. My contractor only did the 2' perimeter insulation. In your opinion is this OK?


In General questions | Asked By curtis bischof | Jul 14 16
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