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10 Answers

Should I fill up unvented soffits with cellulose or block them off?

Hi all, I have a c. 1915 house with two gable vents. Until about a month ago, the attic had no access. I installed an access and have been busting my butt getting rid of the knob and tube wiring so that I can insulate. My ultimate goal is 18" of insulation, r-60 i believe. My climate zone is the zone four, but one county to the north is zone five.

Now, to my questions...

In Green building techniques | Asked By Adam Sick | May 8 15
3 Answers

Cracks in an airtight drywall approach

Hello - I installed drywall in my cabin last summer without any poly vapor barrier, following the fundamentals of the airtight drywall approach. Over the winter, fine cracks appeared at some of the drywall seams. This appears to be a common issue with unheated cabins experiencing large swings in temperature & moisture. Now that my air barrier has been compromised I'm not sure what I can do. Repairing the cracks seems futile unless I can provide a heat source during the coldest months.

Any suggestions?

Thanks for your help,

In General questions | Asked By Richard Baumgarten | May 9 15
3 Answers

Who do I contact or is analysis done here?

I have a new construction house that is designed and ready to be built.

I am satisfied with the layout, but need expert analysis on choosing the insulation and HVAC strategy.

I want someone to look specifically at my plans and advise me on this particular project. I am unsatisfied with the "spray foam seems to work well, or i sell a bunch of...." responses that I am getting.

Who performs this type of service? How do i find someone reputable?
Do I just upload plans here in another post?

I live in Northern NJ zone 5A.

Thank you for your help

In GBA Pro help | Asked By Brian McDonald | May 4 15
9 Answers

Repairing roof nail holes

I am having siding installed, and the installers are using a scaffold built with two ladders, each ladder attached to a single 2x4, and the 2x4 is nailed with two nails to the roof.

First, is this considered a routine type of scaffold? Or would knowledgeable people be upset about nails in the roof?

Second, what is the most durable repair? Roof jacks appear to be installed by lifting shingles and only creating nail holes under the shingle. Then the nail is pounded in and sealed. So, there is no exposed hole.

In General questions | Asked By Erich Riesenberg | May 6 15
1 Answer

Insulating my granny flat

I just purchased a home that has a back studio. We has 2 days of a heat wave and it was suffocating. I investigated and the attic crawl space has no insulation. And the studio interior wall are all paneling and there is no insulation behind. I spoke with an insulation installer/ handyman and he said he could blow insulation into the walls from outside. My concern is, will the paneling hold up against the insulation? I have spent a lot getting this house together and I'm a but limited now and can't afford having someone come in and drywall

In Energy efficiency and durability | Asked By Mary Norrup | May 9 15
2 Answers

The age-old question: open- or closed-cell foam?

I know the questions has been asked a hundred times. I'm building in zone 3. I'll be using Zip System R panels. The living room and kitchen is open and under a cathedral ceiling. Everytime I think I figure out what foam to use, I read another article that tells me the opposite or my builder or insulation guy says something different. I know with the zip system it needs to dry to the inside so I was leaning toward open cell in the walls. The cathedral and the other parts of the roof is where I really don't know what to do. That's why I asking the experts here.

In General questions | Asked By Eric Chandler | May 9 15
3 Answers

OC Foam in Exterior Walls

I am a homeowner buying a new house in the Boston area, climate zone 5. The finished area of the house will be in the 5000-6000 range including the basement and attic. I got involved after some work was already done. Namely the roof deck has been sprayed with open-cell (OC) foam. I have a separate discussion going with Martin and Dana on that topic.

The question now is related to exterior wall insulation which needs to be decided. The builder is planning to do the following:

1) Closed-cell (CC) spray foam on interior basement walls and basement rim joists

In Energy efficiency and durability | Asked By David Amenhauser | May 8 15
14 Answers

Open cell spray foam on roof deck & vapor retarding primer


In Green building techniques | Asked By David Amenhauser | May 4 15
3 Answers

16 ga. or 18 ga. wire for lighting circuit?

LED lights are 5 watts.
Do we still need 12 ga or 14 ga wire?

In Building Code Questions | Asked By C Darwin | May 7 15
3 Answers

Is a radiant barrier a good idea for rigid foam under siding?

I have posted many details and questions in this separate post: http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...

In Energy efficiency and durability | Asked By Chad B | May 8 15
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