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1 Answer

External wall details

I have been in Canada, BC, for three years now having previously been a main contractor building very energy efficient homes in Europe based towards the PassivHaus standards. I am currently a certified energy advisor and have been asked by a client to help him out with his new house build. As the construction methods are different here I'd just like a little advice, or back up, for the following detail.

Asked By Ray Smith | Sep 26 10
17 Answers

Best detail for EPDM on SIP roof? Second Try

I'm surprised I didn't get no even one taker on my question. Perhaps it's because I posted it under the wrong Q&A Category (Energy Efficiency and Durability), so I'll try again here.

I will be self-contracting my own residence. SIP walls and 1/4:12 slope roof, EPDM roofing material.

Unfortunately, when I have to explain to local builder/suppliers what a SIP is, any answer I might get locally does not seem reliable to me.

So I have searched the web to find how the best approach, is but no luck yet.

Asked By Robert Car | Jun 24 10
2 Answers

Footing and foundations winter work

Hi all - I am in process of building a new home in Ashburnham Ma. and my schedule is working out that I will be in process of starting the foundation (footings and slab) in October. There is obviously a possibility of this foundation and slab to sit unprotected during the winter months while I wait for a weather break to do framing. The foundation will be fully insulated using ICFs and the slab will have 4" XPS foam under it. The house hopefully would be very close to PHI standards.

Asked By Mark Dickerson | Sep 17 10
14 Answers

Ventilation required for attic solar power vented fans.

I went to a product seminar last week and one of the presenters was showing an attic solar power vented fan claiming exhausting air up to 1300 cfm per 1600 sqft of ceiling area (Volume didn’t matter, he said). The rep. said that no additional venting was required other than the 1/150 sqft per code on ventilated attics.
I thought the intent of the code was for passive ventilation.

Asked By Armando Cobo | Apr 5 10
19 Answers

Urethane spray foam on exterior above grade block walls?

I was talking with a urethane spray foam installer this morning who stated numerous concerns about all other spray foam products but his - more notably open cell products. He says they do not perform in areas such as rim joists, etc. They don't belong anywhere but in stud cavities on sidewalls. Go figure. He is currently spraying my neighbors' exterior above grade block wall foundation(in addition to 4-6" below grade) wall with a closed cell spray foam. He said there was a study that indicated this is as efficient as spraying the main floor 8' exterior walls.

Asked By Mark Miller | Aug 20 10
8 Answers

Insulation of Floor above damp basement

I have a cement floored basement with some humidity in summer which I control with a dehumidifier. I am having the sills and bays air sealed with foam and am planning to add insulation to the ceiling (of the cellar" with R-19 fiberglass. THe contractor is offering 3 choices, but no advice. 1. Place batts up against the floor with vapor barrier against the floor; 2. place unfaced batts up against the floor with poly ethylene barrier stapled to the bottom of the joists; 3.

Asked By Jack | Aug 12 10
3 Answers

Unvented roof deck

I am finishing an existing work shop with a low pitch vaulted ceiling. There is no practical way to vent the ridge. Since it is a shop, no code applies to r -values, but we want the most we can achieve.
Here is what I am working with:
Mixed climate ( Central Virginia)
2 x 12 rafters 24" o.c. 5/8 osb roof deck, full coverage ice shield and 50yr shingles 2 1/2 / 12 pitch
~ 685 sq. ft. ceiling area
2 x 4 sidewalls 16" o.c.
Concrete slab floor ( vapor barrier or insulation under is unknown)
Sheetrock is proposed for the final wall covering
Tight budget

Asked By JTN | Jul 27 10
1 Answer

Ventilating An Underground Chamber

Given the following:

1. Location of the underground chamber is in a humid tropical location.

2. Facility is off-the-grid.

3. Chamber size is 20' x 30' x 10' (height = 10' ).

4. Sources of electricity are roof-mounted solar panels.

5. Chambers meant to shelter 6 people.

How will be the essentials of a design for a good ventilation system be like for such a facility?

Asked By Boniface Willy | Jul 23 10
2 Answers

Where does one recycle vinyl siding and other PVC waste in Connecticut?

Are there any vinyl siding and PVC recycling companies or centers located in Connecticut? Is there a source for this information because the DEP in Connecticut has absolutely no information as to where or what to do. They only list PVC as a potential recyclable material. This information would be beneficial to many builders and remodelers throughout our state and throughout New England. It should be posted at the State of Connecticut site also. Thanks for your help.
Ed Palma

Asked By Edward Palma | Apr 8 09
3 Answers

How to waterproof and insulate old foundation walls from the outside?

Is 2" XPS over dimpled membrane over blue skin a good idea? Should the foam go up all the way from footing to the rim joist which is 3' to 4' above grade? Or is it better to stop the foam at grade level? If going up is better choice, how to protect and finish the above grade portion of the foam? The foundation is 8" concrete block which is flush with brick veneer of exterior walls. Location - Ontario, Canada. Your input will be very much appreciated.

Asked By Andrei Sosnovsky | Jul 5 10
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