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5 Answers

Please Help!!! Dimple membrane a necessity?

In General questions | Asked By Rasheed Warith | Nov 14 17
10 Answers

Question on direct vent fireplaces

I am gut renovating and expanding a circa 1920 cottage. I am trying to get as close to net zero as I can. I am an architect fairly well-versed in the principles and techniques of net-zero, DER and Passivhaus my firm having designed and built two Passivhaus and 13 net zero homes, all of which have had their performance measured and verified. The point of this bragg-y credentializing is to head off the inevitable finger wagging that usually comes upon mention of the very idea of including a fireplace in a home that aspires to net zero. I get it. Not a good idea.

In Green products and materials | Asked By user-6954517 | Nov 18 17
5 Answers

Possible to use Vented attic in conjunction with Open cell spray foam?

Hello there,
I am a General Contractor in Miami, FL (Hot and humid weather!) and I may get screamed at for asking this question, but is it possible to use continuous ventilation at the soffits (vented attic) in conjunction with Open cell spray foam (sprayed to the underside of the roof sheathing)?

In Green products and materials | Asked By 5221lefty | Nov 15 17
7 Answers

Help with installing a solar water heater using solar electric modules

I'm a solar contractor in the Philadelphia region. I've installed traditional solar water heaters using flat plate collectors but a homeowner has asked me to install a solar water heater using solar electric modules and a heat pump. This is new to me, I did some basic online research and came across an article on this site written by Martin Holladay, "Solar Thermal is Dead."

In General questions | Asked By Anil Babooram | Dec 17 13
7 Answers

Flat roof attic insulation

My home was built in the late 1890s and has a flat roof. It has aluminium siding and it has two floors and basement. On the second floor, we have sheetrock ceiling. There is an older plaster and lath ceiling on top of the sheetrock. There is about a foot of space between the ceiling sheetrock and plaster ceiling. In the attic, there’s no insulation at all. On the edges, you can see the stud cavities that run down to the second floor. You can only see down to the second floor and not the first floor. So not sure if it is called balloon framing.

In Energy efficiency and durability | Asked By michaeldrehl | Nov 17 17
3 Answers

Cut-and-cobble for a three-season cabin

I have a 3 season cabin in (Zone 7) of northern Wisconsin. 2x6 walls 16" OC. The cabin is sheathed in OSB,

Exterior foam of 3" is not an option. The cabin is 20x26' and I plan to cut & cobble 2" XPS on a table saw and fill the cavity with fiberglass batts. Granted...this is time consuming....but there's no hurry. I realize this doesn't address thermal bridging. My concern is longevity with OSB in a northern climate & still being insulated. Yes...I will install a rainscreen if vinyl is not used for siding material.

In General questions | Asked By Dan Musielski | Nov 17 17
11 Answers

Site built ventilation baffle moisture issue

I installed site built rigid foam ventilation baffles per GBA article http://www.greenbuildingadvisor.com/articles/dept/musings/site-built-ven...

In General questions | Asked By Michael Prisco | Nov 17 17
2 Answers

1-1/2" wide rigid foam strips on interior of wall studs?

I was recently speaking with a contractor who said a builder he knows of is installing 1-1/2" wide strips of rigid foam on the interior side of each wall stud to stop thermal bridging. He is doing this as a more affordable method than applying rigid foam to the exterior. He is the installing furring strips for drywall. Is anyone doing this? I am also curious how thick these strips would have to be to effectively stop thermal bridging. It seems reasonable to me but I want to make sure this approach would be beneficial.

In Energy efficiency and durability | Asked By Brian Ducharme | Nov 17 17
1 Answer

Primary Damper for Tulikivi wood stove?

Climate zone 6, Minneapolis.

I had a Tulikivi wood stove installed last week. The double wall stainless steel chimney has not been installed yet. There was no plan for a primary chimney damper. I feel the need to be able to close or reduce the draft when there isn’t a fire going. It would be left completely open when we have a fire going.

In General questions | Asked By jim sweazey | Nov 17 17
9 Answers

Helping my insulation contractor make the right decisions. :)


Good insulation contractors around here are hard to find. A lot of people are doing the work without understanding many of the techniques shared on this site and others. I talked to the person I am considering for my new house and I think I could use your help in educating him a little.:)

1) Radiant barrier in attic

In Energy efficiency and durability | Asked By Norman Bunn | Nov 17 17
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