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10 Answers

Metal standing-seam hot roof

Hi I'm building a new home for our family and wanted to run our roof design by you as my concern is moisture/ condensation. Essentially we have 2x12 members on a low-sloped 2 5/8" over 12 large 3500 square foot roof. I'm planning on insulating with 7" of closed cell (More if recommended) and no vapor barrier because of closed cell not needing it. The roof deck will be covered with Ice and Water HT and then have a standing seam metal roof installed on top of the ice and water. We are located in Massachusetts. One debate is do i use CDX , OSB Standard or advantech.

In GBA Pro help | Asked By Michael Carreiro | Feb 12 17
4 Answers

How do I insulate an unsheathed exterior wall that has 6" stone veneer?


I am in the process of renovating a 1920 bungalow in Kansas City, MO., zone 4 or 5. I wish to make it as tight and efficient as possible, maybe even net-zero with a 6.3 KW grid tied PV system. I have it gutted now as the combination of neglect, a failed tile roof and unique original construction shortcomings made saving any of the interior impossible.

In Green building techniques | Asked By Jim Gottsch | Feb 13 17
14 Answers

GBA blog dated 2015: "How to Insulate a Foundation"

I've read many articles from various reputable sources as well as this one from GBA http://bit.ly/2lAt69b and I have a follow up question...

Martin, you've recently replied to my retrofitting basement questions regarding insulating a 1974 bungalow in climate zone 7a, so thank you.

In General questions | Asked By Todd | Feb 10 17
1 Answer

Stone veneer or XPS?

Question I am building new house and have XPS 2" on exterior on foundation wall running below grade and above grade was wondering if anyone can give me some Technique
Was thinking about using a stone veneer on the concrete that is above grade anyone that I ask says need to remove the xps from the foundation wall on exterior to attach stone veneer question is there a way to attach stone veneer leaving xps on wall Thank you

In General questions | Asked By Boris Rubinstein | Feb 14 17
4 Answers

Multi-speed inline exhaust fan

Is anyone aware of an inline exhaust fan that has multiple speeds so it can do low continuous ventilation and on-demand ventilation?


In Mechanicals | Asked By John Ranson | Feb 12 17
9 Answers

Best way to reduce interior humidity in tight house?

I have been building and refining my "best practice" for 20+ years. I have built a house with walls wrapped in XPS foam (sheetrock-->2x6 with fiberglass batt--> osb--> XPS--> rain screen--> cladding). All XPS joints are taped. The roof is TJI cathedral with blown in open cell foam under plywood, under shingles. The sheetrock finishers had turned up the heat inside to 71 degrees and the temperature dropped last night to the upper 20's. I'm building in zone 4A. There is a conventional HVAC system with fresh air intake motorized damper.

In Green building techniques | Asked By mtndrew | Feb 9 17
3 Answers

Where is the best place to go to get a building science education?

I am a young builder looking to learn more about building science. I do a lot of research on the internet but I think my time could be better spent in a classroom, virtual or otherwise.. I've looked in to yestermorrow but would like something geared more specifically to building science. I subscribe to the fine Homebuilding podcast and building science corporation. They have really opened my eyes but I would like a more formal education.

In General questions | Asked By Spencer Shemwell | Feb 12 17
4 Answers

Insulation recomendations?

Hi our new house is being built with 2x6 walls with exterior CDX plywood with Enviro Dri on the exterior. I'm debating open cell in the wall cavities vs dense pack cellulose. Any recommendations on either for both comfort and long term pay back. Is there any other options i should consider? Thanks for your help

In GBA Pro help | Asked By Michael Carreiro | Feb 13 17
5 Answers

Building envelope and insulation for new build holiday home

I am sorry this is so long, but your expert thoughts are greatly appreciated!
- In the planning stages of a two storey holiday home with an unheated garage below and 2 bedroom with living area and small bathroom on the second floor.
- 40 x 30’ foot print, about 800sq ft for the living area. 1:12 “Flat” roof
- Climate zone 4 marine (north of Vancouver, Canada). Temperature rarely drops below about 28F and the building will be unheated and unoccupied for long periods in winter. Summers are warm but typically not humid.

In Plans Review | Asked By Quinn Sievewright | Feb 13 17
9 Answers

Crawlspace insulation

Hi everyone - Looking for some clarification around how to best re-insulate a crawlspace that has falling fiberglass batts.

The crawlspace is under an enclosed 3 season porch (no heat or AC), the crawlspace has insulated steam pipe and h/c water pipes running through it. The vents were previously covered with plywood (but not air sealed). The house also had termites, so I need to be able to continue annual termite inspections.

In Energy efficiency and durability | Asked By oldhouse7 | Feb 1 17
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