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2 Answers

Polyiso and ZIP

We are looking to build next year, and have to build with a certain builder, wife wants a certain subdivision. We are in Prince Edward Island, Can. on the border of Cold/Very Cold zones probably around 4500 HDD. They will build with 1" foam on exterior. I'm looking to maybe consider ZIP sheathing with hopefully 3" polyiso (1.5" over 1.5") over top then blown-in in 2x6 wall. Will the ZIP system plus ridgid foam allow me to not have interior vapor barrier. Any ideas to help steer this ship.
Thanks in advance, Marty

Asked By marty nichol | Nov 28 14
3 Answers

Instrumenting a new house with moisture/temperature sensors?

I'm building a new house, and I'd like to wire it up with moisture-content and
humidity and temperature sensors to track the ebb and flow of moisture through
the building envelope. Now is the time to do it, as the walls start going up.

Does anyone have any suggestions on techniques and equipment to do this?
Cost is certainly part of the equation (this would be a fun side project). On the
other hand, I can do electrical/electronic assembly and wiring to help keep the
cost down (as long as it doesn't invoke too much time, the other variable).

Asked By Madelyne Schnauser | Nov 27 14
8 Answers

How to fix an attempted insulation retrofit on a '70s cathedral ceiling?

I discovered this website 6 months too late!

After losing heat through a 70's era cathedral ceiling built on 2 x 8 rafters for more years than we liked to count, we decided to replace the roof, sheathing, and insulation in one operation. The area of the hip roof was bid at 2,230 sq. ft., the cathedral ceiling comprising 2,040 sq. ft., leaving a small attic space above bathroom and hallway areas under the peak.

Asked By Gregory Erickson | Dec 16 13
12 Answers

Most sesible heating system for a new house build on Vancouver Island

We are in the planning stage for new construction of a 2 level 2600 sqft home on Vancouver Island. As we're in the process of allocating budget we would like to know what the most sensible heating system to use will be. We require electricity to be our primary source with wood heat as back up, as we lack natural gas and propane is too expensive. We understand that base board electric is the most cost effective for install, but we're looking to improve efficiency, durability and sustainability with increasing energy costs in mind. As far as we know our options are as follows:

Asked By Blake Klopfenstein | Nov 26 14
10 Answers

Mold on inside of plywood sheathing

I recently purchased a super insulated house in the Concord, NH area. The house is 3 years old. From my investigation and discussions with the previous owner the wall system is double stud insulated with 3 layers of 3.5" Roxul Comfortbatt. The sheathing is Huber Zipwall with taped joints. The siding is cement board clapboards nailed directly to the sheathing. The inside is drywall and I'm told gasketed at joints and electrical outlets. there is no interior vapor barrier and the paint appears to just be regular latex.

Asked By Aaron Saucier | Nov 25 14
3 Answers

Window flashing and trim with exterior rockwool

Were building a home on Vancouver Island (4C) and are planning on split insulation strategy as follows:

1" X 4" strapping>1.5" roxul comfort board> building paper > 1/2" sheathing > 2X6 structural w/ dense pack cellulose > drywall with vapor retardant paint.

Asked By colin slade | Nov 25 14
2 Answers

Does HRV/ERV system reduce your electricity cost?

Hi,

I live in Thailand which is a tropical region. Temperature can get to 100F in summer

I am in interested in installing HRV system in my house. Some people say installing HRV system can reduce electricity cost due to less air conditioning power needed.

Please share if you pay more or less for electric bill after installing HRV system.

Thank you very much

Asked By Chanpakong Visondilok | Nov 27 14
1 Answer

Best practices ideas for retrofitting existing PWF built in muskeg and best practices for foundations for new builds in muskeg (i.e. very wet !) and a severe cold climate

The existing PWFoundations are wet (many moldy) and have dirt floors. the crawlspace is heated with a baseboard to keep plumbing from freezing. House shifts with freeze thaw action on the spongy ground. Looking for ideas for retrofit - can remove non-draining back fill, install a skirt of frost protection, backfill with free draining materials and can cover the dirt floor with sealed poly. need to make the crawlspaces a cleaner and warmer conditioned space. Any other ideas to achieve this?

Asked By Gail Lawlor | Nov 27 14
6 Answers

ThermoCore Roof SIPs - 8" Panels

Anyone here use or have any experience with the ThermoCore SIPs? They are based out of Indiana and have a 8" polyurethane SIP ( I know about the blowing agents) with a R-50 value that I am considering using for my roof. Zone 4B

Some key points:

1 - I will be air sealing all interior panel joints with a T&G connection, caulk, gasket, and finally a peel & stick tape to ensure complete air tightness.

2 - I will use an ERV

3 - On the exterior I plan on putting a peel & stick butyl membrane that is vapor impermeable and then a standing seam metal roof.

Asked By Peter L | May 5 14
16 Answers

Spray foam insulation

I have a 100 year old house in Zone 5. There is a sunroom (approx. 5'X20') on the south side of the house which is all windows. It is built on piles (about 4' to the bottom of the joists) and open underneath with lattice. The room is open to the living room of my home and is heated by 2 forced hot water radiators. When we bought the home the floor was insulated from underneath by batt insulation and rigid insulation between the joist cavities. We had an energy audit performed when we moved in and were told this was all good. Still, the floor has always been cold.

Asked By Danny Mac | Nov 17 14
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