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3 Answers

Has anyone ever used stacked IGUs in a homemade window?

I'm building a shop for my small construction company and have some insulated glass units that I saved from previous jobs. Has anyone ever used stacked IGUs in a homemade window?

I was thinking of making one removable like a storm window.

In Energy efficiency and durability | Asked By chad zeman | Mar 19 15
7 Answers

Rigid foam overcoat method on my own house

Been reading this website on and off for the last 7 years or so. I really appreciate the knowledge base here.

It is time to re-roof my own house, Denver, climate zone 5b. I plan on incorporating something similar to the JLC August 2014 article, "Project Overcoat" with a couple of caveats.

In Plans Review | Asked By Matthew St Martin | Mar 20 15
4 Answers

Damp crawl space in a dry locale

Hi all,

I came across a damp crawl space in an eastern Arizona home (Show Low, warm summer Mediterranean (Koppen classification: Csa). The dirt crawlspace floor is damp to the point of transferring bulk moisture into the knees of my pants, with mold covering a lot of the attic floor. (I backed out and put on PPE before proceeding.)

In Energy efficiency and durability | Asked By Jason Owsley | Mar 18 15
18 Answers

Drainage plane between sheathing and rigid foam

I am working on an addition project located in Wisconsin. My plan was to use Huber Engineering Zip wall sheathing.

In reviewing Zip walls installation instructions, I noticed that Zip calls for a minimum eighth of an inch drainage plane between the rigid foam and the sheathing. In my wall section I planned to include a drainage plain (rain screen) on the outside of the 3 inches of rigid foam.

Will the recommended Zip wall drainage plane reduce the effectiveness of my foam insulation?

In Energy efficiency and durability | Asked By Jason Stringer | Jan 30 11
2 Answers

Air seal my house during renovation

We are renovating a house we bought on the St. Lucie River in Port St. Lucie Florida. I was advised to air seal the house as long as the walls and ceilings are accessible. My contractor has no clue what I am talking about. Please advise how to find a knowledgeable person in the Port St. Lucie area who can assess and advvise. Many thanks

In General questions | Asked By E.S. sHULZ | Mar 20 15
4 Answers

PEX in Chicago: a gamble worth taking?

I've recently begun the renovation of a frame construction two-flat in Chicago. Its two separate apartments with a basement and an unfinished attic. I have researched PEX and would love to use it to replace all the rusting galvanized metal water supply lines. The main advantage for me is that a PEX manifold and homerun-style system would give both apartments equal water pressure during use ( ie. I don't get a cold shower while my downstairs renter does the dishes) BUT Chicago apparently doesn't allow PEX as a potable water supply line.

In Building Code Questions | Asked By Matthew Lamothe | Mar 20 15
1 Answer

How to attach rigid insulation to crawl space floor

I am located in Zone 3B, Orange County Ca.

I am going to seal my crawl space and insulate the walls with rigid insulation. Here is the code from the CEC Residential Compliance Manual:

"Insulation: The R-value of insulation placed on the foundation stem wall shall be

equal to or greater than the wall insulation above the raised floor. Stem wall

insulation shall run vertically along the stem wall and horizontally across the

crawlspace floor for a distance of 2 feet (24 inches)."

In General questions | Asked By keith messick | Mar 20 15
5 Answers

Attic insulation advice/feedback

We recently moved into a 1952 Cape Cod home and will be remodeling the entire 2nd floor attic/living space so now is the time to get the insulation done right. As a result, I have been doing considerable reading on the topic of insulation and would greatly appreciate some advice on my current plan to “cathedralize” and insulate this space.

The plan:
Vent the soffits.
Create a 1 inch deep soffit to ridge ventilation channel in each rafter bay using .5 inch rigid XPS foam board sealed in place with caulk/spray foam.

In General questions | Asked By Chris Kolloff | Mar 18 15
1 Answer


Has anyone seen any study on the relative energy costs and savings of sun tubes? I have a client interested in one of these and I'm not sure if it's a good idea in general.


In Energy efficiency and durability | Asked By Dan Kolbert | Mar 19 15
1 Answer

How do I integrate rainscreen at soffit?

I'm installing a rainscreen (1x4 battens) over 3" of polyiso foam and 3/8" plywood. I'm in Northern CA, zone 3B. My WRB will be Tyvek wrap over the foam. I understand how to terminate and vent the rainscreen at the bottom of my wall, but am not sure what this rainscreen should do at an arched soffit above my door opening.

Attached are a photo of the framed soffit above the door, before installing the rigid insulation. Also is a photo of this detail sketched out.

In Green building techniques | Asked By Dan Burgoyne | Mar 19 15
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