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3 Answers

Joint compound over poured concrete wall

I would like to plaster then texture over old uneven concrete. I saw a product called plaster-weld. Can I use the plaster weld over the poured concrete wall and then just layer on coats of joint compound to get a textured even finish, then seal with a primer and finally paint it? When they formed up the basement walls years and years ago, they weren't concerned with even finish. I can send you a photo if you need one. We get very little moisture in basement. Thank you in advance.


In PassivHaus | Asked By Chris Sutherland | Feb 21 13
12 Answers

Passive house exterior door for reasonable price?

Has anyone come across an exterior door that provides good insulation and beefy frame that's worthy of a super insulated home but comes at a reasonable price? Any suggestions would be appreciated.

In Green products and materials | Asked By Matthew Michaud | Feb 4 13
13 Answers

What is an acceptable air barrier separating showers and tubs as referenced in the 2009 IECC Section 402.4.2.2?

I live in Zone 5 (No.NV) and it has been the local custom to place unfaced batt insulation in outside walls between showers and tubs in new construction. Line item 13 of the referenced Inspection process under the 2009 IECC specifies an air barrier to be used. I'm a certified HERS Rater performing these inspections, but having much resistance to this item.

In Green building techniques | Asked By Leon Mills | Feb 13 13
3 Answers

Unvented rainscreen?

Great website. Thank you! I am building a home on my farm in CA (zone 4B). 2x6 construction on top of a 4-inch concrete slab on pandeck over an ICF daylight basement. Incorporating passive solar concepts, going off grid with a 4400 watt array. Heating with a woodstove in our wet and mild winters (very rarely gets below 20F). Hoping a tight envelope, R-25 walls and an R-36 roof, thermal mass in the slab, and opening all the windows during our generally cool-ish nights will keep us comfortable in our very hot and dry summers (regularly over 100F during the day).

In Green building techniques | Asked By Galen Weston | Feb 19 13
19 Answers

Looking for help designing a durable & efficient wall for a house in the mountains near Asheville NC at 4,000 ft. elevation

I am trying to use articles from this site and from Building Science to design a durable and efficient wall for a residence in the mountains near Asheville NC at 4,000 feet of elevation.

Which would be a better wall; a 12" AAC wall with interior plaster and exterior stucco, or an 8" AAC wall with 3" of closed cell spray foam or XPS sheets on the exterior and then a 1" air/drainage space and then hardiplank? Would the increased complexity and cost of the second option be worth it? Are there any good spacers for the air/drainage plane that are not thermal bridges and will not corrode?

In Energy efficiency and durability | Asked By Stuart Murray | Feb 11 13
3 Answers

ERV with filter MERV 13 or greater?

Hi, does anyone know if there is an ERV with a MERV 13 or greater filter?

In Mechanicals | Asked By Ed Siff | Feb 20 13
10 Answers

Can polyethylene on top of your rainscreen prevent inward solar vapour drive?

I am working on a wall design for a super efficient home (near Passive House standard). The double stud wall with cellulose insulation, and a fibreboard exterior sheathing (no polyethylene vapour barrier on the interior) will- in places- have a stone veneer as the exterior cladding. Because we live on the west coast of British Columbia (similar climate to Seattle), and because some of the walls are south and west facing, I am concerned about inward solar vapour drive.

In Energy efficiency and durability | Asked By Burke Stoller | Feb 19 13
10 Answers

Bathroom Exhaust Fan drafts...


I was wondering if folks had any suggestions as to how to reduce cold air infiltration/drafts from bathroom exhaust vents.

I've found that in some of my bathrooms, cold air is coming into the bathroom from the overhead ceiling exhaust fan. When I go outside, I see that the exhaust pipe has a simple damper on it. I imagine that when the wind blows, it can easily get up and into the exhaust duct and the damper doesn't stop it.

Are there products that can help resolve this issue?


In Energy efficiency and durability | Asked By Morris Scott | Feb 20 13
14 Answers

Plaster on poured concrete interior wall?

What kind of plaster can I apply directly to a poured concrete wall? Insulated on the outside, new construction. Do I need something that breathes and gives with the wall as it dries out? Should I wait for a period of time after initial construction for walls to dry out?

Thanks---- Greg

In PassivHaus | Asked By Greg Gunderson | Feb 6 11
3 Answers

Cost to install exterior foam or Roxul?

I am curious about what the installation labour costs are for exterior insulation boards - foam or Roxul. For comparison, lets just say one layer that does not include taping or caulking. Does anyone have a cost per square foot of wall or floor area that they charge or have paid?

In Energy efficiency and durability | Asked By Patrick Walshe | Feb 20 13
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