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5 Answers

What's the best wall height for a ductless mini split heat pump?

Hello out there,

In Mechanicals | Asked By Theresa Spear | Oct 26 14
2 Answers

Question from the field... performance after cutting spray foam

Hey all,

I'm a contractor interested in building performance. It's common practice that after installing windows and doors, you spray foam to seal the rough opening. This then gets cut back to accept drywall/trim/siding.

I've always wondered if cutting the spray foam affects the spray foam's performance? Before cutting, the foam develops a nice hard skin and it seems to me that doing away with this might be a bad thing. Is there any data on this?



In General questions | Asked By Steve Hull | Nov 16 14
1 Answer

Water control at foundation - placement of perimeter drainage


In General questions | Asked By Lucyna de Barbaro | Nov 16 14
1 Answer

What are typical crawspace air leakage vectors?

I've done a little bit of searching and not come up with much except that its a common phenomenon, i have a very old probably more then a century balloon framed house with a 70/30 basement/crawlspace, and the blower door showed a lot of air coming from the crawlspace, and i've gone in there (a messy and claustrophobic endeavor) but did not find any obvious places air was leaking into the house from.

In Energy efficiency and durability | Asked By Alan B | Nov 16 14
1 Answer

EPS exterior insulation thickness

Looking to purchase a 1975 home with 2x4 cavity filled walls. This house will be stripped back to the studs on the interior and the exterior windows and doors replaced as well as siding. I want to add a few inches of eps insulation to the exterior with strapping. How much insulation is required so the walls can still dry to the exterior as I will have interior poly? I live in edmonton alberta Canada. Your guys help is much appreciated

In Energy efficiency and durability | Asked By Sheldon Lee | Nov 16 14
10 Answers

Walkout frame to basement connection - big problem!

I have what seems to be a major issue - to me anyway. as you will see in the photos, I have a framed walkout basement wall with concrete retaining walls at a 90degree angle to both ends. How in the world do I flash/seal this from the outside to ensure that air/WATER does not enter?

-House will be covered in brick veneer
-Retaining walls will be covered in brick veneer

I leave for two days and this is what happens... framer does not insert sill seal gasket between vertical wall stud and concrete (this will change tomorrow).

In Energy efficiency and durability | Asked By Jeremy McGill | Nov 12 14
3 Answers

Proper underlayment for unvented asphalt roof

I recently purchased a house in suburban NYC. The roof is currently two-layers asphalt shingles with the most recent layer about 27 years old. We have been told and seen evidence of ice dams from the prior winter (lots of snow in Jan 2014). The primary area of the ice damming was in a cricket connection of a covered deck to the house which we have been told by various roofers was improperly built. We do not have the option of correcting the flawed design. We will be putting a new roof on within the next couple of weeks and need to determine the best design.

In General questions | Asked By K Thomps | Nov 14 14
7 Answers

I'm trying to figure out a fastening detail for an assembly with Warmboard and rigid insulation.

What do you think of the following fastening options? Or is there another method I should consider?

1. Wood Blocking in Metal Deck, Fastening to decking below
2. Fastening through to metal deck
3. Z Purlin Fastening to metal deck

Images shown in order of options listed below:

In Green building techniques | Asked By Heather Gayle Holdridge | Nov 12 14
2 Answers

This may be a problem...

I read the GBA news item that an Arizona agency recently said that smart meters were not a danger to anyone. This has me worried. Up until I read that I hadn't the slightest doubt that they were safe. I maybe showing my age but this gives me the same feeling I got when a certain president said "I am not a crook!".

In General questions | Asked By Eric Habegger | Nov 13 14
1 Answer

Regarding air sealing of sheetrock.

I notice the heavy emphasis on sealing and caulking sheet rock at all joints. I always thought that once the sheet rock is taped and mudded that it would be airtight. What am I missing in my understanding of this newer technique? I live in Minnesota and it is common here to use a poly vapor barrier instead of this caulking method. What should we be doing here in our arctic like climate?

In Energy efficiency and durability | Asked By terrance kaase | Nov 14 14
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