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3 Answers

Insulation Issue: Renovating EPDM low slope cathedral ceiling with flash and batt and venting problems

After researching GBA to death, I have come to the conclusion I need to ask the experts. Forgive the novel but I’d rather explain in as much detail as I can.

I am in the midst of an addition/renovation project and have hit a major snag with the roof/ceiling. I’m never going to achieve GBA nirvana, but ‘good enough’ is better than what I had. My grandfather built the house in the 1960’s and it was recently willed to me, but it’s time for changes. Kudos to my grandfather for building a freakishly strong house, but not a well insulated one.

Asked By Robert I | Jul 15 16
2 Answers

Near zero / passive home builders in mid-west Georgia?

I am ready to initiate process to design-build or retrofit to passive house standards in Muscogee county, GA or Lee county, AL. Having trouble locating experienced near zero / passive house builder outside of Atlanta, any ideas?

Asked By David Floyd | Jul 15 16
0 Answers

Should I pay to have all current roof vents removed during a foam cathedral attic retrofit?

There are 8-10 square black vents in my current vented attic plus two active vents (both of which I believe do not work.. .we just bought this house but since I intended to foam the attic I did not care whether they worked or not). Is it worth paying to have all of these roof penetrations removed and the area flashed and reshingled, or just leave them as is and foam around and under them? None of the insulation or energy companies that have given me bids have mentioned the existing vents at all. Does it matter much which way I go?

Asked By John Sexton | Jul 6 16
9 Answers

Attic insulation question

I have read many of the posts and articles about different ways to bring an unconditioned attic into the thermal envelope of one's home and I'm currently weighing some options. I will likely use spray foam under the rafters of my attic (9.5 inches). I've read the various debates about using less spray foam than would be required to achieve the desired R-value (eg R of 49 in my zone 4a area), with the argument (from the spray foam manufacturers it seems) being that spray foam yields a more effective R-value so you don't need as much as you would think based solely on R-value calculations.

Asked By Rob Moore | Jun 17 16
10 Answers

How can I stop the mold recurring in my wall?

I have a bonus room over my garage with a double window at the gable end. The outside of the wall is brick faced, wrapped in Tyvek over OSB. The inside has fiberglass insulation, and drywall. The house is 12 years old, located in the Midwest.

Asked By Carr Bruton | Jun 18 16
16 Answers

How do I vent this floor sleeper assembly? Or do I need to? Help!

Redo of old commercial alley space.. 2 story brick bldg turned into sfd

Floor assembly:
1. built on existing slab on grade that is about 1" above grade in an alley
2. existing slab had some cracks in it and some plumbing with short plumbing trenches in it. 6/23/15
3. 6 mil poly layer
4. 2x6 pt sleepers joists at 16" oc solid blocked about 4' oc 6/25/15
5. 3" closed cell foam sprayed in joist bays 6/30/15
6. 3/4" t&g osb floor sheathing 1st week of July/15
7. 5" wide 3/4 solid red oak flooring on flooring paper. 8/12/15
8. Client comment about cupping 10/15 or 11/15

Asked By Carey Hoobler | Jun 6 16
13 Answers


I am trying to come to grips with SEER, COP and HSPF.

Is this correct:
SEER is BTU cooling / watt hours needed. So divide this number by 3.412 to get the COP. Thus a 16 seer unit would have a COP of 4.7 or so.

HSPF is BTU heat produced / watt hours needed. So take a heat pump with a HSPF of 10, which is supposed to be pretty good and divide that by 3.412 = a COP of 2.9.

Have I done that correctly and, if so, are there heat pumps that do better than a 10 out there?

Asked By Amanda Evans | Sep 10 09
6 Answers

How do I prevent ice dams in this area in the future?

House is in North Central NJ, zone 4a, 2x4 construction, built 2005-6, ~4500 sq ft, insulated with batt insulation, unfinished and unconditioned attic with gable, ridge, and soffit vents. We are not the original owners so didn’t have a say in the design or build specs but there are clearly lots of elements that run counter to many of the views espoused here e.g. complicated roof design, 2nd floor heating/cooling unit and duct work in attic, house not air sealed or as insulated as it could be for a modern home, etc. That said, we like the house and area and plan to make some improvements.

Asked By Rob Moore | Jun 5 16
10 Answers

Stamped concrete patio near foundation

Hi all,

I have a couple of questions regarding a patio near the foundation of our house. My wife and I have been dealing with water issues in our basement/crawl space for a while now, and we just recently had a contractor in to seal the vent properly, install a membrane along the foundation wall, and add French drains tied into the downspout.

As the last part of this work, we have removed a surface deck that the old owners installed and are looking to install a stamped concrete patio with the same dimensions (14x30) pitched away from the home. Specifically my questions are:

Asked By Ryan Lambert | Mar 19 16
11 Answers

Basement slab reinforcement

Not really a "green building" question per se, but too much knowledge and too good a response time for me to not ask here.

Asked By Jim Tyler | May 19 16
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