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2 Answers

Will I need to install wood sheathing on my century-old house before installing rigid foam insulation panels?

Underneath the wood clapboard siding, there are only bricks and mortar in between the 2X4 studs.

In Green building techniques | Asked By Anthony Zitelli | Sep 11 13
16 Answers

What is the best approach to insulating an enclosed attic re-model?

I have read many of the posts about creating an enclosed attic space but they have mostly spoken about new construction. We are considering spray foam and have been quoted 5.5 inches of open cell to an R-20. Most of our HVAC equipment and ducting is in the attic spaces hence one of the reasons for enclosing. With a 1950's block and stucco wall and windows home, what should I try to achieve in terms of attic insulation for an enclosed attic space? Still want to be able to use the space for storage.

In Energy efficiency and durability | Asked By Woody McMahon | Aug 27 13
7 Answers

Should truss builders include duct chases?

I specified open-web trusses for my new house in part to simplify the installation of mechanical systems. Recently, I discovered that the truss system would not support metal ducts. There simply wasn't a way to get from the mechanical room to the other end of each floor using metal.

I was annoyed that the truss company had not included a clear path for running metal ducts. My builder defended the truss designer by saying we did not include a duct design (for long and complicated reasons I won't get into here).

In Mechanicals | Asked By Steven Knapp | Sep 10 13
3 Answers

Is it practical to use solar to warm a slab in my shop?

I am currently in the process of building a shop 3/4 of which will be below grade and have a poured slab with radiant coils in the floor, I have equipment which I will be working on and consequently be lying on the floor. My question being in Southern New England on the coast will it be useful or cost effective to try and supplement the heat in the building with solar thermal panels to heat the concrete floor? thanks Chas.

In Green building techniques | Asked By Chas de Geofroy | Sep 10 13
1 Answer

Looking for diagram showing how to detail felt or housewrap under 1.5" foil faced foam with window sill extension

Hi, Hoping you can direct me to a good diagram showing how to detail wall and outie flanged window particularly for exterior foam insulation. We are set to begin within a few days and I am worried it won't be done correctly. It is 2x6 wall 24"oc with 2x8 window box extension. The 1 1/2 foam will go over osb covered with #15felt (OK?) Vinyl siding (no furring?). We are in climate zone 5. I have poured over 100's of articles and cannot seem to find how to detail the felt (or other product) correctly when the window is built out.

In Green building techniques | Asked By Mel Meehan | Sep 10 13
2 Answers

Siding/insulation/WRB/drainage etc. -- shorter question


I have a question with somewhat less detail than my last volley :)

I am building a new house 100 yards from the ocean - elevated approximately 10' off grade. fiber cement siding

Connecticut shore - 4+ or 5- mix of humid/warm and first cold zone = maybe 40 rain days... near water - driving rain elevated (somewhat protected by large eaves and gable end over hangs). right on the edge of both zones.

Specs - as they stand right now. Still a few weeks out (can easily change up to application for building permit). From inside out:

In GBA Pro help | Asked By pat rowland | Sep 10 13
4 Answers

Not caulking vertical seams on siding

I’m about to put up siding on a building enclosure that includes a WRB, taped XPS and furring strips. The siding will be a combination of lap wood siding (front) and ColorPlus Hardie Plank (the rest). All butt joints will be flashed. My question is limited to the seams in which the siding contacts vertical trim.
I am in agreement with Martin not to use caulking as it seems to cause more problems than it prevents (http://www.greenbuildingadvisor.com/community/forum/green-building-techn...)


In General questions | Asked By mark moses | Sep 9 13
2 Answers

Thickness of rigid insulation

I am planning to replace the slate siding of our house with clapboard vinyl siding and I want to install 1/4" or 1/2" rigid insulation. What if the rigid insulation will make the J-channel protrude on doors & window jambs? Is there a way to fix these?

In General questions | Asked By Domenick Delaware | Sep 9 13
1 Answer

Replacing windows

We need to replace 21-year-old windows in a 2x6 wall.
Can I use 4" windows?
If so, what are the modifications needed and are there any concerns we should be aware of?


In General questions | Asked By Kathy Carpenter | Sep 9 13
10 Answers

Pier foundation: floor insulation and HVAC

Hello All,

My wife and I are in the design stages of our new home. We are building 2.5 hrs north of Toronto, Ontario (borderline between a 7a and 6a climate on a forested lot.

I'm a contractor and my business partner is an Architectural Engineering Technician. Our goal is to design and build a 1800sqft 1.5/2 story labour of love that is as efficient and green as our budget will allow.

We are planning a 2x6 wall assembly with 1"EPS and wet-spray cellulose, somewhere in and around R-28.

In Plans Review | Asked By Kyle Newman | Sep 6 13
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