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1 Answer

Before people understood the need for a rainscreen gap

These days, conscientious builders usually install siding over a vented rainscreen gap. But back in the old days, however, wood siding was usually nailed directly to the sheathing, with only a layer of asphalt felt or housewrap between the siding and the sheathing.

When siding was installed without a rainscreen gap, the siding took a long time to dry after every rainstorm, and paint didn't last very long.

In General questions | Asked By Martin Holladay | Dec 5 14
3 Answers

Air leak under new glass sliders

We just had new glass sliding doors installed a few months ago (there used to be a very old swinging door in that location, so the hole was enlarged and a new header was put in).

Now, I can feel a lot of cold air leaking in from the bottom. There is no moulding between the laminate floor and the door yet - I am in the process of putting quarter round moulding there, but there is a kick-lock so its taking me a long time to get the cut-outs right to fit around the kick lock.

In Energy efficiency and durability | Asked By Matt Solow | Dec 4 14
1 Answer

Should I fill the unvented soffits with foam?

We have an outbuilding that's about 12 x 13 that we want to turn into year round writing / guest room.
It has a basement where well equipment is located. We've sealed and insulated the ceiling and the floor joist bays above the foundation and covered with 5/8ths wallboard. With a tiny heater that comes on intermittently in the cold weather, the basement stays about 42deg F so the pump doesn't freeze.
We plan to improve the ventilation for the warm months when some condensation occurs.

In Green building techniques | Asked By Rob Cramer | Dec 4 14
11 Answers

Flat roof with no gases or fumes


I am renovating a home in Laguna Beach CA and redoing the roof as well as most of the house. I am highly sensitive to chemicals and the engineer is calling for the following:

1. Ply
2. 4” High Density Rigid Insulation Foam
3. CDX sheeting
4. Mule Hide roof system

I am wondering if you have any suggestions about how to create a gas/vapor barrier so that when the roof heats, I am not exposed to fumes/gasses from the materials. The inside will be finished with 1/2” drywall board.


In Green building techniques | Asked By Kimberly Norton | Dec 2 14
7 Answers

T&G cathedral ceiling with 1/2 inch XPS instead of gypsum wallboard?

Hi out there,

New to this forum, thanks for having me.

Jumping right in. I'm getting ready to insulate and finish a cathedral ceiling in a small cabin (~600 sq ft of lid) and trying to get the details right.

I've been reading the suggested courses of action elsewhere on this site (http://www.greenbuildingadvisor.com/blogs/dept/musings/how-build-insulat...) and here is the plan I'm thinking of at the moment:

In Energy efficiency and durability | Asked By Eric Taylor | Nov 29 14
0 Answers

I bought an Eichler-style home in central Florida with a flat Ickes-Braun skylight

I bought an Eichler-style home in central Florida with a flat Ickes-Braun skylight, 8x20 ft.
There are five 4x8 ft panels.

In GBA Pro help | Asked By rick baynton | Dec 4 14
8 Answers

Adding mechanical ventilation to a leaky house

I have an older home that I know leaks a lot of air, and I’m wondering if adding mechanical ventilation would improve the indoor air quality.

When i first bought the house, it tested over 10 ach/50. I have since improved the basement by air sealing the rim joist, service penetrations and the slab to foundation wall cracks etc. The house was last tested around 8 ach/50 so this helped, but obviously the rest of the house is still very leaky.

In Mechanicals | Asked By Mark Fredericks | Dec 3 14
60 Answers

Insulating basement rim joist

Hello, without taking too much of your time, can you please just assist me in a recommendation for insulating my basement rim joists? very small basement, very old home, block walls..

In Green products and materials | Asked By Dave Mac | Dec 1 14
17 Answers

Insulating an unheated basement / cellar

Hello everyone,

Thank you for the great site and apologize in advance for lengthy first post.

I have a small room (6'x20') in the basement that is currently unheated and uninsulated under covered porch. Ceiling and walls are concrete and there is no visible water penetration. There is exterior door separating this room from the rest of the finished basement (conditioned/insulated)

In Green building techniques | Asked By Chris kim | Dec 2 14
1 Answer

Why is my roof decking not matching up on the corners of the hip ridge?

I have built a 16'x20' deck with a hip roof and a cupola, on one side my roof decking matches up perfect and on the other side on both ends the plywood runs out and doesn't match the adjacent side. It is the same on both ends on one side 4" long one the 20' side, I started the layout of the decking the same on both sides and one side is good and the opposite side is not. I don't understand this all four ridge boards are the same length and all cut on the same rake.

In General questions | Asked By Chance Bates | Dec 4 14
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