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5 Answers

Aluminum door threshold

hi everyone, does anyone know if/where you can purchase a door threshold similar to the one in my picture? i did not find anthing in the gba product guide... thanks

In Green products and materials | Asked By erik olofsson | Mar 9 13
3 Answers

Rigid Foam vent channels

Martin Holladay, if you are out there, or etal:

Martin some time ago you posted a reply to Gary Steinfeld where you stated "you can use rigid foam to create a ventilation channel." I like this idea and would like to plan on using a foam ventilation channel in a cathedral ceiling application, followed by FG between the rafters and another layer of foam on the underside of the rafters. Some have suggested firmly that the vent channels be WELL air sealed.

In Energy efficiency and durability | Asked By Bob Brown | Mar 9 13
4 Answers

Townhouse Deep Energy Retrofit

I recently purchased a 1970s townhouse in northern VA. The property was neglected for about 20 years, the T-111 siding had holes that various animals large and small had made over the years. Roof has several leaks judging the the interior and from the degree of wear on the outside. Other than that, the house is actually in surprisingly good condition.

In Energy efficiency and durability | Asked By Roger Lin | Mar 8 13
12 Answers

Double exterior wall question

Since I already own the OSB sheathing for our new central Indiana home, I’ve been stressing over all the concerns with using OSB in a double exterior wall assembly. I’m trying to come up with a solution that keeps my sheathing on the exterior of the double-wall assembly – and prevents it from turning to oatmeal!!

Is there a concern with assembling the exterior wall as follows:

1) Frame 2x4 exterior structural walls. The sole plates would sit on top of foundation. The interior walls would rest on top of floor system.

In Energy efficiency and durability | Asked By Matt Judson | Mar 5 13
2 Answers

Townhouse Retrofit Ventilation

On the same TH project I asked about today. I am trying out a couple of scenarios for ventilation too. Ever since reading John Semmelhack's report on the cost effectiveness of HRV/ERVs I've been wanting to try out exhaust only ventilation systems.

I think the set up can be relatively simple. Replacing existing bath fans with Panasonic FV-08VKS3 (80 cfm) or FV-08VK3 (50CFM). Since this house will end up being relatively tight, we'll need replacement air. I am thinking about putting FV-GKF32S1 in each of the bedrooms.

Here are some questions:

In Green building techniques | Asked By Roger Lin | Mar 8 13
2 Answers

How should I finish brick and concrete block walls on a partially completed house I aquired?

I aquired a "shell" of a house and I am looking to finish it. The walls are brick facing backed by concrete block protected by a hip roof with wide overhangs. The brick is in great shape and the roof was just replaced. The interior is completed to the point of stud walls laying out the rooms. The house is not insulated and is still bare block on the interior side of the exterior walls. The windows are single pane glass and will be replaced. The house was started in the 1950's and made weather tight but never finished inside.

In Energy efficiency and durability | Asked By Dan Harbaugh | Mar 2 13
6 Answers

Register locations

In constructing a very tight near passive house (1 1/2 story) with a hydronic hot air system is it ok to place all registers (supply and return) up high or on the ceiling? The HRV is integrated in the heating system (NuAir Enerboss). One of the return registers is close to the wood stove to hopefully move some of that heat around the house.

In Mechanicals | Asked By Elizabeth Kormos | Mar 7 13
2 Answers

Is emulsion paint waterproof?

We have peeling paint on a chimney breast in a bathroom. It's ordinary emulsion paint. Some peole say I need special waterproof paint to cure the problem I think I need special breathable paint to let the moisture flow in and out of the wall without knocking the paint off. I can't find a clear answer as to whether normal emulsion paint is vapour proof. I imagine it depends a bit on the type. We used vinyl silk as its a bathroom, I imagine this is less permeable than matt. I get the general impression that emulsion paint is a bit permeable, not fully 'breathable' but not fully 'vapour proof'.

In General questions | Asked By henry parr | Mar 8 13
4 Answers

Compare merits of dense pack fiberglass vs dense pack cellulose in walls + loose pack in ceilings

Dense pack fiberglass is now easily available from reliable contractors and carries a higher R value than cellulose. Cellulose is more environmentally friendly. Some assessments suggest cellulose does better at higher depths and is able to absorb moisture better. What other things should be taken into consideration when choosing cellulose vs fiberglass dense pack for a wall design that includes 2x6 walls with 4" polyiso (could reach R45 which is "high performance" in VT with fiberglass and not cellulose) and planned 2 ft loose pack in ceilings? Thanks!

In Energy efficiency and durability | Asked By Phil Lawson | Mar 7 13
2 Answers

Green adhesive

Hi all, does anyone have a good recommendation for a non-toxic low or no VOC adhesive like liquid nails? I'm gluing some cedar panels to a wall in my kids closet. The wall behind it has various low voltage wiring behind it and I want to avoid using nails or staples. Thanks.

In General questions | Asked By Eric Schroeder | Mar 6 13
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