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15 Answers

Roof venting doesn’t decrease AC load

Martin, in Fine Homebuilding, you wrote that roof venting doesn't decrease air conditioning load (http://www.finehomebuilding.com/2017/07/11/roof-venting-doesnt-affect-co... ).

Which leads me to ask what roof venting IS good for. Humidity control? Presumably, venting doesn't increase heating load in the winter.

In Energy efficiency and durability | Asked By Robert Fankhauser | Jul 15 17
2 Answers

Book signing event in Lyndonville, Vermont

This weekend, I'll be signing copies of my book and answering questions at a bookstore event in northern Vermont.

GBA readers who live near Lyndonville, Vermont -- including residents of St. Johnsbury and Littleton, NH -- are invited to Green Mountain Books (1055 Broad St, Lyndonville, Vermont) between the hours of 10:00 am and noon on Saturday June 10.

Of course, copies of my book, Musings of an Energy Nerd, will be available for purchase.

In General questions | Asked By Martin Holladay | Jun 9 17
2 Answers

Vinyl over insulated floor on piers in cold climate

Hi, I have a cabin on piers, with insulated floor. The joist bays are filled with fiberglass bats, bottom side is covered with 1/2 chipboard, sealed and battons at the seams. Vapor barrier on the top / warm side, and 3/4" t&g plywood over that. So far it's been warm and dry and critter proof. I'm in Canada, winter temps in the -5 to -25 deg C are not uncommmon.

In General questions | Asked By Randy Toni | Jul 13 17
1 Answer

Refinishing painted cinderblock walls

1954 rambler in Minneapolis, Minnesota here. I am in the process of refinishing our basement after some slight water intrusion last year caused us to discover mold growing on our old tar paper behind knotty pine finishes. We concluded it was due to water weeping behind the walls and then collecting on the tar paper, a problem that had been ongoing for decades with no obvious failure until now.

In General questions | Asked By fishybass | Jul 17 17
5 Answers

Air sealing kneewall with I-joists beneath

Hey my name is Josh and I live in Maryland zone 4. Excuse if my terminology is off, that's why I'm including some pictures. I just moved into a 2002 built 1 and 1/2 story home. I'm trying to do everything I can to seal and insulate the home because I don't the builder had energy efficiency in mind.

In Energy efficiency and durability | Asked By Joka | Jul 16 17
17 Answers

Synthetic roof underlayment (low perm material) as Stucco WRB?

Given the history of prior stucco failures and what we have learned, would it not be prudent to use a WRB with an exceedingly LOW perm rating with a wall assembly designed to dry to the interior? I am planning stucco on a residential structure in Zone 5 (despite the barrage of don't do its, it fits the architecture of the home). Thus have been stopping into jobs randomly where stucco is being installed and find most contractors apply two WRBs under stucco. I've seen a wide permutation of choices.

In Energy efficiency and durability | Asked By Sal Lombardo | Jul 9 17
22 Answers

Properly installed can light vs. surface mount

I am doing more research in lighting after an earlier question and reading other articles. The general consensus I am seeing is: Can lights are evil. The logic? Because of air leakage.

In General questions | Asked By Nicholas C | May 1 17
5 Answers

Exterior foundation waterproofing

I recently had my foundation wall treated with a spray on waterproofer. I noticed a week later that there were little pin pricks throughout the black layer. Some of the pin pricks you can see concrete through. Is this a typical occurrence or should I have the company spray the wall again? I am mostly worried that it will cause the waterproofing to be defective due to moisture instrusion. Thanks!

[Editor's note: Photo below.]

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In General questions | Asked By Chris Roche | Jul 16 17
4 Answers

Roof retrofit for non-cathedral, non-low slope roof

I've read several items about adding exterior insulation to existing roofs but haven't found the detail that I'm looking for.

We have just purchased what amounts to a one story ranch home with a walk-out basement in Central WI built in 1985. The basement is block except for the walk-out wall. The walls are 2x6 stud construction with fiberglass and poly. The gable roof is framed with standard (not energy heel) trusses 2' o.c at 4/12 pitch. There is a also a small intersecting gable addition with that roof framed on top of the original gable roof.

In Green building techniques | Asked By Scott Lind | Jul 14 17
4 Answers

What is the optimum insulation and roofing solution for a low-slope cathedral ceiling/roof?

I need some advice, please. I own a mid-1950s rancher with a cathedral ceiling/roof in Hershey, PA. The slope of the ceiling is about 3 ft of rise in 11 feet of run. The ceiling is drywall, to which acoustical tile is attached. The character of the space from the ceiling to the roof is unclear. The gap between the ceiling and roof deck is 6 inches. The roof is unvented. The soffit does have some venting, but it does not seem like a lot. The "attic" has fiberglass batt insulation that likely is in failure. The problem is interior moisture.

In General questions | Asked By Need to learn | Jul 15 17
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