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1 Answer

After reading for months, getting 4 quotes from spray foam contractors in my area, and undergoing an energy audit, I'm in the process of finalizing plans for open cell half-pound Icynene application to the bottom side of the roof deck in the attic. This is a retrofit job. Within the attic is a furnace in a closed room vented directly to the outside. I have a few questions after I received the proposal today from the contractor

In Energy efficiency and durability | Asked By Kevin Hilton | Jan 11 12
4 Answers

I have a client with a roof valley that has ice damming problems ever year due to poor design and snow drifts off higher roofs. The valley end into a wall section . Other than installing de-icing cables does anyone have a suggestions

In General questions | Asked By Christopher Lorden | Jan 10 12
9 Answers

Looking for the expert opinions regarding the use of "earth tubes" to temper incoming ventilation air. I understand that in some climates, that moisture must be carefully managed to reduce the risk of mold etc. The idea is appealing for those of us in climates with hot summers and cold winters.

In General questions | Asked By Garth Sproule | Nov 14 09
1 Answer

I have read through your articles and watched the videos on using polyiso for exterior sheathing and insulation. After spending quite a bit of time researching this issue, I would like to know your comments on the following.

I live in the Seattle area and have spoken to a company in Portland with a similar weather environment about the best way to accomplish the above. They recommended using polyiso 1 1/2" over my existing 1/2" CDX sheathing on the exterior (I am doing a remodel with new siding) by Hunter (no foil or material on it) followed by a housewrap for a water barrier.

In Green building techniques | Asked By Steve dorsey | Jan 10 12
1 Answer

The new tiles, the glue to set them and the finishing polish are offgassing. What ventilation rate is recommended to maintain good IAQ and for what time period?

The rooftop units are set for 10% fresh air at the Economizer and we have the fans on Manual. Any suggestions will be appreciated.

In Building Code Questions | Asked By Dick Rome | Jan 10 12
2 Answers

We are looking to start documenting your client’s building process for their dream design from the ground up. This will be a great opportunity for your firm, as it will be featured throughout the episode

Do you have a unique design plan for your client? Do you have an ultra-modern or out of the ordinary floor plan? Are you building your client’s property somewhere people would never consider? Is your project design so interesting and innovative that it would WOW all of America?

Here are some links to previous episodes shot in the UK:

In General questions | Asked By Casting Producer | Jan 9 12
6 Answers

I am trying to explain on my blog how we plan to insulate a house that will be built in the next year. I was wondering if it is possible to use images or free videos from Green Building Advisor on the blog. I wanted to ask before I did it.

I don't know how to use AutoCAD, haven't yet learned SketchUP so I might have to go the Lucas Durand way and draw these things by hand and then scan them in.

Thank you.

In General questions | Asked By Lucy Foxworth | Jan 9 12
7 Answers

I just had my home insulation completed with 3/4 lb open cell foam. I am wondering if I need to spray a vapor barrier on it before I drywall. It is 10" thick on the roof deck.. do I need to spray that? Also has anyone thought of advantages to adding a reflective barrier on top of the foam? Last, does anyone recommend a fire retardent paint sprayed to the exposed foam on the roof deck for safety? I dont neccessarily want to complete any of these, but dont want to regret what i should have done after it is covered.
Thank you for any feedback -

In General questions | Asked By Scott Jacobs | Jan 9 12
5 Answers

A Mn based SIP maker (Enercept) told me they can make a SIP panel with integral ventilation under the outer layer of OSB. I was hoping for such a thing to help reduce the issue with rot at the peak of a roof SIP panel. Yes, interior air barriers are crucial as well, but it would seem that ventilation between the foam core and the outer layer of OSB would be helpful as well. One way they can do it is by grooving the EPS foam before applying the OSB. I think they have another way (firing strips). Has anyone used such a product and if so, what pros/cons did you encounter?

In Energy efficiency and durability | Asked By Robert Alf | Jan 9 12
18 Answers

I am part of a volunteer fire dept in the NEK of Vermont and we are building a new firehouse. We want to build it as energy efficient as possible since it gets used seldom (hopefully). Just a little different from most homes around since it's only heated to 55 not 70.
Our plan is the following from inside to outside

5/8" Sheetrock
Poly Vapor Barrier
2x4 stud wall with fiberglass insulation
Double layer of 2" Green Guard staggered joints
2x4 stud wall with fiberglass insulation
5/8 Advantec Sheathing
Typar Housewrap
Vinyl Siding

In Green building techniques | Asked By Dana Patoine | Jan 5 12
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