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10 Answers

Best wall system for Vermont?

I am building a modular home in Chittenden County Vermont and have been debating what type of wall system and insulation combination will be best. There are three wall systems under consideration, but I am open to alternatives.

1) 2x8 framing 16" on center with Roxul cavity insulation (R30) and Thermalstar sheathing w/1.5" EPS foam (R7.5) for total R-value of 37.5.

2) 2x6 framing 16" on center with Roxul cavity insulation (R24) and 2" polyiso rigid foam (R13) for a total R-value of 37.

3) 10" double stud 2x4 wall, BIBS cavity insulation and Zip sheathing for total R-value of 39.

In Energy efficiency and durability | Asked By Craig A | Apr 29 16
12 Answers

Best furring strip over exterior foam to hold Hardie siding?

Ok, this has come up before and I want to get final recommendations from those who have done the work in the field as my foam board is almost finished.

I have attached 2.5" of recycled EPS to the exterior over my drain wrap. Windows are INNIES and are flashed well. As a point of fact, the Tyvek brand tape worked and adheres excellent to the EPS. I have some 3M all weather tape but the Tyvek tape works great and is easier to work with.

In Energy efficiency and durability | Asked By Joe Suhrada | Apr 26 16
3 Answers

Another cathedral ceiling and insulation

Greetings, I have a home in climate zone 4c that desperately needs some insulation, last summer I was seeing 90+ interior temps. And burn 4 plus cord a year to stay warm.

Built in 1954, the whole house is vaulted ceilings. All 2x8 cavities, 16" oc. There is continuous soffit venting and no ridge vent. About 2" batt insulation.

I plan to reroof to achieve the r value I want. My plan was roxul mineral wool r30 batts in the bay's, resheet roof with zip sheeting, followed by 3" polyiso.

In General questions | Asked By Scott Brzoska | Apr 29 16
4 Answers

Is this my best foundation choice?

First off, Green Building Advisor has been invaluable in my research to design my future home and have found it well worth the membership cost. So thank you, to all you who have made this site what it is.

I am planning on building a 1700 sq ft ranch style straw bale house near Cortez Co (climate zone 5B). Currently I am sketching up layouts, making lots of notes on building techniques, choosing home fixtures (doors/windows), HVAC systems and researching different build options, before I take my plans to an architect so he can refine and incorporate them.

In Plans Review | Asked By Ken Hodge | Apr 29 16
1 Answer

Perlite for walls vs Dense pack Cellulose

Hello-
Has anyone used loose fill perlite for wall cavity insulation on wood framed exterior wall. I am interested in the least toxic insulation for the walls. But I am a little concerned about the moisture retention capabilities of perlite. Does the perlite dry out quickly in a normal framed wall?

Also, does dense pack cellulose have less capacity for moisture retention?

Lastly, has anyone used loose fill perlite for attic insulation.

In Green building techniques | Asked By edward kramer | Apr 30 16
0 Answers

Cellulose comparisons

My new construction will be getting dense pack in the walls. I've been looking at National Fiber's

In Green products and materials | Asked By daniel f. vellone | Apr 30 16
0 Answers

roofing and insulation on old house

I have an 1850s farmhouse I'm renovating. To insure good insulation, I had the attic rafters spray foamed with closed cell foam about four inches deep.

I'm trying to plan for an eventual re-roofing, and I wanted to know if there are any best practices I should keep in mind at that stage for eleminating any issues that might arise from the spray foaming. The old roof has a few layers of shingles on it.

Is there a recommended roofing type for this situation? Any ventilation issues I can helpfully prevent moving forward?

Thanks,

Ilmari

In Green building techniques | Asked By Ilmari Polojarvi | Apr 30 16
4 Answers

Insulating floor of mudroom before closing it off

I'm building 5' by 8' mudroom addition where there previously had been a dilapidated porch-like structure. I've poured the foundation and secured the sill. The concrete foundation is about 5 inches above soil, then 6 x 6 sill. I will be framing the floor with 2x 6. I'm stuck with these dimensions because of grade etc. This "crawl space" is NOT connected the the main house's crawl space and will be 100% inaccessible once the subfloor goes down. Also, foundation is non vented.
Anyway- the plan is to-

In General questions | Asked By Joseph Moore | Apr 29 16
9 Answers

Hot water heating

Need some advice on my domestic hot water plan...
very long and narrow ranch house... well water. good pressure..

Master side of the house has Master bath. (with soaker tub), 3 other full baths and a half bath.... all fairly close to each other...

kithcen side is very far away.. (75-100 feet away) ... has a full bath , half bath, and kitchen sink...and a washing machine.

On Master side i am planning on a large heat pump water heater( i have a good utility room for it) attached to a manifold with 1/2 lines to showers, 3/8 lines to sinks and toilet.

In General questions | Asked By Dean Sandbo | Apr 13 16
1 Answer

Green Building Advisor Q&A

Thank you to those involved with the elimination of all of those asian-alphabet, unreadable, virus-like comments that had taken over this site this past week. I enjoy checking out the question section of this site when time allows, and when I saw those "comments" I moved on to other things. THANK YOU !!!

In General questions | Asked By KEVIN ZORSKI | Apr 29 16
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