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6 Answers

Practical insulation and air-sealing techniques needed for a (sort-of) enclosed crawl space

(If this should be posted elsewhere- feel free to move it, or tell me where to repost it.)
I have a fairly typical Chicago-style, narrow (like 22'), 2-story, balloon-framed house that was built in the 1880s or 1890s, and converted to a 2-flat later.
At some point (maybe in the 2-flat conversion?), the 2-story back porch was enclosed, and the new siding was continued down to grade level- by adding some framing between the wood columns (on piers) that support the porch.

Asked By Ben Rush | Aug 30 14
5 Answers

Air and thermal barrier continuity in ceiling over garage

Good Morning All,

I am building a new structure (northern end of zone 3) and will be using the 100-year wall approach with a low slope metal clad roof (yes white colored). 2 x 4 construction on the exterior walls (yes, I know about OVE) with Zip cladding, then 2 - 1" xps lapped sheets on the exterior and most likely rockwool in the cavities.

Piece of cake? Except!!! the ceiling over the garage (which sits under the 2 stories above). The garage will most likely be CMU with no insulation (cold space).

Asked By leo kloop | Aug 25 14
17 Answers

Off-grid house needs... gasp!...air!...gasp!

Hi,
I need some advice...preferably before I cut a bunch of holes in the walls or ceiling and find out that this was a pointless venture.

So the details:

900sq foot one level, mostly open plan, highly insulated and sealed home.
Heating climate...like really... a lot. -40 C is not unheard of for stretches of time. More typical is -20 C

The house is powered completely with PV.

Heat is supplied by radiant slab, a bit of passive solar. I am also putting in a small wood stove in the next few days.

Asked By keith ahlstrom | Aug 21 14
3 Answers

Recommendation for window flashing tape?

I am in the process of shopping for window flashing tape and am running in circles about what brand (and type) of flashing tape to purchase. Obviously, price is a consideration, but I do not want to sacrifice quality and longevity.

Asked By Matthew Michaud | Aug 20 14
5 Answers

For a large scissor truss (top chord 31" above bottom chord), we want around R-70 but no more

For a large scissor truss (top chord 31" above bottom chord), we want around R-70 but no more. How do you 'contain' the blown in, or how would you use batts?

.

Asked By David A Flannery | Aug 18 14
2 Answers

Is a partial unvented roof retrofit a bad idea?

We are in Minneapolis with a 1923 Tudor house. Last year was our first winter in the house. We had bad ice damns last year and there is plenty of evidence it has had problems in the past. The second floor is a full story and consists of a shed dormer addition with no venting that I can see. The rest/original of the roof has minimal venting due to lack of (none) eves. There are only pots, but no soffit venting. Half of the story is unconditioned attic is accessible and is on the same floor as the living space. Access through a full size door.

Asked By Joe Sweeney | Aug 4 14
5 Answers

How can I remedy a cathedral ceiling with fiberglass batts in unvented rafter bays that now emits a strong musty odor?

Investigation revealed 3 problems: 1) no soffit vent; 2) insulation extending beyond the end of plastic rafter vents closing off the air channel up to the ridge vent; 3) no blocking above the wall to seal up the fiberglass. I've corrected the first two and caulked the ridge on the inside, but am unable to fix the blocking. The odor persists and I fear the fiberglass is contaminated with mold that the revived air flow won't be able to dissipate. Would pulling out the fiberglass (through the soffit to avoid major deconstruction) and filling the bays with foam work?

Asked By Michael Roland | Jul 25 14
3 Answers

Foundation/floor strategy for a heated workshop in Zone 6A

I am planning a 30'x22' farm workshop in Eastern Ontario, Canada. I want to end up with a level floor suitable for woodworking machines (table and bandsaws, planer, jointer etc) , Floor will be on grade, location is on a small rise and I will make sure there is good drainage away from building. I will place 2" of SM insulation under floor. I will most likely frame double stud walls and insulate with 6" to 7" of Roxul.

Asked By mark godfrey | Jul 26 14
6 Answers

How to condition an existing crawl space?

Hi. I haven't been here for a while because I thought I had found the solution to my crawlspace problem but alas I haven't. I had been dehumidifying the crawlspace at our beach house with a high capacity Santa Fe dehumidifier which unfortunately got destroyed when the crawlspace was flooded during Superstorm Sandy. Rather that buy a new one, I had a vapor barrier installed, replaced the open vents with insulated smart vents and had the underfloor of the house covered in 2-3" of closed cell spray foam.

Asked By Cherylann Schieber | Jul 17 14
1 Answer

My question is on the suitability and application of foil-faced rigid foam to exterior walls with our climate conditions

I am a homeowner, little sun from Nov to March, average daytime winter temp -8 C, night -15 C, with intermittent -20 C days lasting no more than a week, summer daytime temp, average mid 30 C, night 20 C, with intermittent weeks of high 30 C., average annual rainfall 20 inches, average annual snowfall 60 inches, generally calm, however, can get an occasional rare storm with winds of 20-40 mph and generally low humidity particularly in the winter.

Asked By Marilyn Limbert | Jul 16 14
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