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2 Answers

Cedar wall shingles and rain screens

Wondering what's the better way to make a rain screen is. First option- on the exterior of the studs I'll have 2" of polyiso then felt paper. Then I was thinking of ripping 3/8 plywood into 2"or3" strips and attach them vertically thru the foam into the studs. Then ripping plywood for the horizontal battens for the shingles every 5". Seems like a long time at the tablesaw. Never done this before, might make details around the window tricky?

In General questions | Asked By Seth Kelley | May 5 14
5 Answers

Overpour or not?

I'm preparing to build a super-insulated spec house (R-36, R-60) in far northern Wisconsin. The site has an insulated 28'x40' slab-on-grade already there from a previous owner, and I'm pondering the best way to incorporate in-floor radiant heat into the house. (There is no need to inform me that most energy-interested folks think that in-floor heat is overkill for a super-insulated house.) I just built and sold a similarly-insulated house with a heated slab and no heat source on the second floor, and am looking to do that again.

The two methods I'm considering are these:

In Green building techniques | Asked By Josh Jipson | Apr 26 14
2 Answers

Can you use a tank-less Heater to do both DHW and space heating (hot water baseboard)

We want to combine both DHW and space heating, as we have limited space

In Energy efficiency and durability | Asked By Joan Blood | May 4 14
1 Answer

What are the three most common mistakes with vapor retardars

what are the three most common mistakes with vapor retarders?

In General questions | Asked By Randy Nilsson | May 4 14
4 Answers

I will be adding a room to my house this summer and I am looking at a couple different wall configurations.

Any comments / suggestions / criticisms more than welcome.

Obviously these are not wildly original, they are based on so many great posts here and also on recommendations from BSC.


In Green building techniques | Asked By Greg Smith | May 1 14
3 Answers

What type of building envelope should I use on my resided house in Seattle?

We have a two story house in Seattle that was built in 1976. It has 2x4 exterior walls with R-11 rolled fiberglass insulation between the studs – has brown kraft paper vapor barrier on the inside of the house walls, has foil vapor barrier on the inside of the unheated garage; then on the studs is foil backed kraft paper, ¼” of white foam insulation board, then aluminum siding. It looks like they use slanted 1x4 bracing in the corners for shear bracing. There doesn’t appear to be any plywood on the exterior of the walls.

In Green building techniques | Asked By dale luhman | May 2 14
6 Answers

Triple-pane windows? Cathedral ceiling with Roxul? Minisplit? Affordability?

This might not be the forum for this long question, but, I'm driving myself a bit nuts with all the environmental/aesthetic/monetary values I'm trying to blend in designing and building our house. Maybe there are a few builder-psychologists willing to give council so as to arrive at a workable blend... and to quiet the competing voices bouncing around in my helmut.

In Green products and materials | Asked By Edward Krause | May 1 14
6 Answers

Is there a compatibility issue with Zip (Huber) R- Sheathing and open-cell Icynene?

While constructing a home in Eastern MA and utilizing 11/2" Zip R Sheathing on 2x6 walls, Icynene Open Cell foam was sprayed into the stud bay/wall cavity (against the Foam board backing). Shortly after spraying I checked a few spots to see the consistency of the foam and noticed that the foam had not adhered to the Zip foam board, creating a gap ranging in size from 1/4" to 2". There were a few locations where the foam had adhered, but the majority of the test spots revealed a gap as noted.

In Green products and materials | Asked By Jonathan Hahn | May 2 14
9 Answers

Slab on top of slab: Building science?

I have an existing foundation which is a trench poured monolithic pour, slab on grade with the perimeter foundation walls extending 40 inches to the frost line. It has perimeter stem walls extending 24 inches above the floor slab. The room is unheated, 400 square feet, used 9 months of the year. It has 9 foot walls and vaulted ceilings.

Architectural plans for the room call for the floor to be elevated 14 inches from the existing. The monolithic pour is uninsulated and has no poly in place under it.

In General questions | Asked By Dennis Dipswitch | Apr 29 14
13 Answers

I am thinking of using Huber’s new Zip System R-Sheathing on new construction

I have three questions:
1. What has been users' experiences with this product?
2. Do I need to install a rainscreen over it if I am installing fiber-cement siding?
3. What’s the best insulation in the 2X6 wall behind it? Is flash & batt overkill?

In Green building techniques | Asked By James Kuszaj | Apr 26 14
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