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8 Answers

Limited Budget: Dense-Pack Cellulose or Zip R-3?

We are building a custom house in central Maryland, which is in Climate Zone 4 and has adopted the 2015 IECC.

Our budget is already stretched pretty far, so it looks like we can only afford one of these upgrades to our walls:

(1) Dense-pack cellulose insulation (instead of inexpensive fiberglass batts - exact R-value unknown)

(2) Zip R-3 (instead of regular Zip)

Which of these options would the Green Building Advisor Community recommend?

Asked By user-6890381 | Aug 21 17
7 Answers

Average quality built homes needing makeup air because they are airtight

I have a question in regards to homes being built (not necessarily green homes) that are subject to the new energy code with air sealing and blower door tests. These homes are being built with average, code minimum building materials and after a blower door test it is showing the house is tight enough to require make up air.

Seeing as these are not green homes, there was no plan in place ahead of time for a system to bring fresh air into the house. Are you seeing this as a problem in other states as well?

Asked By Brian Ducharme | Aug 17 17
5 Answers

How would homeowners find a truly green contractor?

Where or how would a homeowner be able to find a licensed contractor knowledgeable in the practices and topics discussed on this site, or even green building and healthier building materials in general? Had hoped to be moved in before the holidays and I'm told there is roughly only one month or less of work remaining to be done... but I can't even find a contractor or subcontractors to do it. Maybe I'm searching in all the wrong places? Any advice or help would be immensely appreciated.

Asked By Natasha Reeves | Aug 21 17
8 Answers

Mild climate; expensive cellulose — What to do?

I am getting ready to go to Engineering for a new house in Raleigh, NC.

HDD - 3247 and going down....On border of zone 3 and 4. Technically in 4 but 20 miles from the 3/4 border.

Being in the South, everyone worries about cooling but we usually have 3x the cost in heat (based on last energy audit).

Asked By User-6902085 | Aug 18 17
15 Answers

3/12 pitch roof insulation

Hi all.
I sent a question and got a reply on a 2/12 pitch roof.

I have an architect working on my plans now. It is a single-slope roof at the widest part (of 32 or so feet).

I originally was going with 3/12 pitch, but he thought 2/12 would be a lower roof at the tall end, so I said fine!

Now, looking at the problems with 2/12, I asked to go back to the 3/12 pitch. So: If I go 3/12, would I (or should I) use R-60 fiberglass? It will have 24 in. parallel trusses.

Would I still need a cupola? (Zone 6, lower Michigan.)

This is TMI for my small brain...


Asked By Robertsoave | Aug 19 17
10 Answers

Trying not to over-ventilate attic with continuous soffit board?

CZ3, 2065 square foot vented attic. Simple gable (36x60). If I follow Joe's advice to split the net free vent area (1/300) to 60 or 65% at soffits and 40 or 35% at roof I'd be aiming to put approx 600 square inches on the two 60 foot sides (300 square inches per side). And then the remaining 400 square inches on the roof.

Asked By Inger Peters | Jul 28 17
2 Answers

Wall Construction Questions

We are building a house in Asheville NC, climate zone 4A, 2,600’ elevation. I’ve read many GBA articles on stucco and wall construction – all good stuff. We will have stucco exterior walls on our house with at least 3’ overhangs, and we are considering the following wall construction:

• Drywall
• Intelligent membrane (do we need one)?
• 2” x 6” stud bays filled with either Mineral Wool, or blow in Cellulose
• Huber 1-1/2” Zip R Sheathing
• Benjamin Obdyke 10 mm Rain Slicker
• Water resistive vapor permeable barrier (which is best)?
• Stucco Lathe
• Hard coat stucco

Asked By Nancy Broadbear | Aug 21 17
1 Answer

I would appreciate a review of an air-source heat pump quote

zone 7 Kenora Ontario, Canada.

I asked for a quote for an ASHP unit that would work for the time being as well as in the near future when the house is expanded...

Some background....

1-short term.. (with the building as is)

-to heat and cool my existing home, 850 sq ft 2x6 framed 20 yr old bungalow on conditioned 5 ft insulated crawlspace...

I completed an online manual J about a year ago and determined as best I could a heat load of about 25000 btu.


Asked By Tim Brown | Aug 19 17
6 Answers

Vaulted ceiling insulation question

I am building a 50 x 60 workshop with 16 ft ceilings in Vermont. We do get cold ... two years ago while building an living in an RV onsite, we had a week with nights of -30 and daytime highs of -10. We have only had a couple of days in the 80's this summer and only average 5 days in the 90's (have had none this year).

Anyway, was planning to use standard flat bottom trusses but like the idea of an insulated attic area .... gable end on the 60 ft wall so lots of attic in the center area of the building.

I am thinking about going with sloping flat trusses with a 24" cord.

Asked By Michael Csele | Aug 21 17
13 Answers

Wall Assembly

Below is a wall assembly of one builder we've looked for the purpose of doing the framing, windows/door installation and the various barriers (WRB, Vapor and Air). I wanted to know everyone's thought are for my climate in Ottawa, Canada.

My opinion is I don't think this is a good wall assembly for the following reason:

Asked By Arnold K | Aug 19 17
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