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4 Answers

Do I use flashing or what?

I have a plywood exterior wall and plan on adding house wrap with built in drainage plane, one inch foam board. If I put 1x4 furring strips on the foam what do I use to keep bugs from crawling up the air gap between the foam and the siding?

In General questions | Asked By Tim Stumpf | Jul 19 12
6 Answers

Concrete Cracks when using sub-slab insulation

On a number of projects we seem to encounter problems when pouring concrete slabs over thick rigid insulation. The insulation seems to interfere with the curing process and we get surface cracks that are problematic when using the concrete as the final finish surface. The concrete that is being poured in unconditioned spaces (like a garage) at the some time do show any cracking even though they were the same mix and poured at the same time. Has anyone found a strategy that might lead to better results?

In Green building techniques | Asked By Ron Flax | Jul 19 12
9 Answers

Adventure is my middle name...

Anyone ever tried attacking a wasp nest with white vinegar?

I wonder, if undiluted, would it have enough kick to achieve the desired result?

In Green products and materials | Asked By Lucas Durand - 7A | Jul 18 12
4 Answers

Vapor Barriers

As a Building Official In Connecticut I am constantly confronted by builders choosing to use kraft faced fiberglass insulation. As we are now enforcing the IECC 2009 installation methods and practices that were wrongly accepted for thirty years need to change. Tabs stapled to the inside of framing members is unacceptable and has been wrong for 30 plus years but acce[ted as common practice and approved. Technically this also does not pass the "continuous vapor retarder required by the IBC and IRC.

In GBA Pro help | Asked By Edward Palma | Jul 19 12
4 Answers

"Innie" Doors?

I'm planning on adding rigid foam insulation to an exterior gut remodel.

I believe I will adding OSB, 2" of foam, 1x4 furring and the fiber composite siding to the existing 2x4 frame wall.

Even if I purchase a 2x6 pre-hung door with a 6-9/16" jamb, it will be short of the new wall. How should I solve this?

In Green building techniques | Asked By Chad Yates | Jul 18 12
12 Answers

Fancy canned spray foam

I see fancy canned foam in the blogs from time to time, with metal triggers and hoses. Where would one buy a setup like this? I'm building my house on weekends and can't seem to reuse cheap canned foam hoses... Maybe there is a trick I don't know about.

In General questions | Asked By stephen edge | Jul 6 12
1 Answer

What is the easiest way to replace the subfloor?

I recently bought a 1970's model mobile home, and its actually in really good condition. Some neighborhood kids broke out the windows in it, and the rain has caused the particleboard subfloor to bow and swell up into big hills throughout the living room, kitchen and hallways. The floor joists are fine. What is the easiest way to rip up the particleboard without damage to walls or framing? There is no ductwork, no insulation, and we need to replace the plumbing anyway so none of that matters. Thank you for any advice, im doing this on my own for the first time and have no idea what im doing.

In General questions | Asked By Angel Jones | Jul 18 12
2 Answers

Roofing Help?

I have a flat roof, 2700 sq foot, single story home that was built in Broward Co. Fl in 1972. Around 1995, the previous owners obviously had some issues and had the roof re-roofed with no tear off (legal to code). What seems to have happened is that the roofers did not enhance or create much of a pitch at that time and my roof pools in particular places, many places. To make matters worse, there is only one drainage area.

In General questions | Asked By Suzi Margolin | Jul 17 12
4 Answers

Rainscreen fastener length

In a rainscreen wall system, is it ideal for siding fasteners to be long enough to pass through siding, furring, sheathing, and still bite into the framing?

3/4" horizontal lumber siding
1x4 vertical furring strips
1" diagonal lumber sheathing
2x6 framing

Thanks for the advice, it's a been hugely helpful.

In Green building techniques | Asked By Richard Baumgarten | Jul 17 12
6 Answers

Correct roof overhang depth for proper solar shading

I used Sketchup to help determine how the solar path would fall on the house I am designing. How do I determine the correct amount of shading/sun?

With the window heights and overhangs I used in the model, at noon on June 21, the entire glazing of the south elevation windows are completely in shadow, but just barely. At noon on January 21, the glass is completely exposed. This seems, intuitively, to be the sweet spot. But should I tweak the overhang to get more shading in the summer months or, conversely, more sun in the winter months?

In General questions | Asked By erik olofsson | Jul 14 12
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