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5 Answers

Attic condensation and leakage in Zone 4C

I have a 1979 Tri-Level house north of seattle which had a water leak running down the masonry i found when installing a gas insert. I'm in process of replacing the cricket, however during the adventures of solving why its leaking, i've learned my roof has some significant condensation issues. Roofers tend to say just add a ridge vent and move on, but having read some of the building science articles here, i want to make sure i'm going the right direction... and if i can change things to be more efficient along the way, i'm all ears.

pertinent facts:

In General questions | Asked By Jon | Dec 30 15
10 Answers

ERV or HRV that scrubs the incoming air?

Hello all, I'm planning a new home and need some help on a ventilation issue. A couple of my neighbors burn a lot of wood in the winter, so much that you smell like a BBQ pit after a few minutes outdoors sometimes. Is there any ventilation system on the market that would scrub incoming air--activated carbon maybe? Or can anyone think of way to alter ventilation ducts on a typical ERV or HRV to do so that is safe for the systems and for me?

In Mechanicals | Asked By Antonio Oliver | Oct 9 14
2 Answers

Density of polyiso compared to XPS?

A local supply house is running a good discount on Polyiso. My builder is familiar with XPS, but not polyiso, and is asking me about the density. How does it compare?

I think the trouble is that he has been bitten by crumbly EPS in the past and doesn't want to go down that road again.

In Green products and materials | Asked By Clay | Dec 30 15
2 Answers

Windows to use in a north-facing Northern California home?

We are in the process on planning a remodel for our home. As part of the remodel we would like to have a "view" wall on the northern side of our house, where the deck entrance is(so we'd have doors too).

What kind of windows/doors would gba members recommend? My current thinking is to use some PVC tilt&turn door-sized european windows(eg imported from Poland) + some fixed windows. However I have not narrowed down any potential windows suppliers yet.

Where should I look for large, efficient, yet cost-effective window options for a cooling climate?

In General questions | Asked By Tom | Dec 30 15
8 Answers

Pole barn insulation?

I have a 24 x 30 pole barn that I want to insulate. My concern is condensation.

I'm in central Floirda, so heating it will not be done. This space will be A/C only.

The walls have been framed up 2x6. The walls & roof are metal. There is 24" overhang that has a complete soffit & gutters. I have a solar-powered roof fan as the vent for attic area. There is no ridge vent.

The metal siding is a corrugated style with foam gaskets, top & bottom, to keep critters out. The walls I planned on drywalling or plywood?

In Green building techniques | Asked By Bill | Dec 28 15
11 Answers

Need No VOCs - How to accomplish?

I have an extreme chemical sensitivity (yes, basically I'm allergic to life! lol), but I want to build myself a tiny home on wheels. I wonder if this can be accomplished.

I think that wool insulation would suit my needs best, but I'm not sure about the exterior because I'm very sensitive to off-gassing materials like Tyvek, etc.

I was thinking perhaps cedar shingles, but would I still need some sort of vapour barrier? Then I was thinking plaster and lathe, but I live in a cold climate with strong winds and temps down to -50°C...

What to do?! Any ideas?

In Green building techniques | Asked By A. Moonstone | Dec 29 15
3 Answers

Trapping moisture in the wall

Hello all, I stay here on the east coast of Canada in a moist, cool climate and am looking into rigid insulation to boost the overall r-value of the wall and to deal with losses over thermal bridging. This is for a new-build.
The standard wall construction for the last while for here is gyprock, 6 mil poly, 2x6 frame with fiberglass insulation, osb or plywood, homewrap and then vinyl siding. This combination works very well but there's lots of room for improvement, espically on the insulation front.

In Energy efficiency and durability | Asked By Dan C | Dec 30 15
7 Answers

Buffalo, NY wall system

I am looking to build an energy efficient house in Gasport, NY (just outside Buffalo, NY) - zone 5a.

Is a double stud wall my cheapest option and should I keep searching for a framing crew & architect willing to-do it?

In General questions | Asked By Jeff Ziegler | Dec 29 15
4 Answers

My favorite radiant barrier ad

This one is fun: It's an ad on GBA, placed by a radiant barrier manufacturer. The only problem is that they misspelled "radiant."


In General questions | Asked By Martin Holladay | Dec 29 15
2 Answers

Insulating crawlspace floor joists vs. walls

We have a home near Raleigh, NC. The home was built in the 1970s on a vented crawlspace on sandy soil. It has batt insulation between the floor joists. The rim joist and the sill plate are untreated lumber on block walls with 2 courses of brick at top of the block.

The crawl space has had moisture problems which have been largely addressed with plastic moisture barrier and 2 sump pumps with perimeter drain and a dehumidifier. There is indication of previous termite problems in rim joist and sill at front and back door but no apparent problems elsewhere.

In GBA Pro help | Asked By Beth | Dec 29 15
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