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3 Answers

How to get rid of that creep in the wall?

My design challenge has been to apply the concept of “outsulation” , 2.5” exterior XPS rigid board, to a wood structure that will ultimately have 3 coat stucco and real stone veneer as final exterior. The project is in Zone 5, new construction, 2x6” wall, stick framing. Have gotten some good insight from Martin, who has directed to me some valuable resources, as well as fellow GBA readers. Ultimately ran it past a local engineer, between his input and the cumulative experience gained by reading, eventually abandoned the idea. Too risky, too much weight, not a proven assembly, don’t do it.

Asked By Sal Lombardo | Jan 10 17
14 Answers

What do you think of this wall makeup?

I've spent countless hours researching (new to energy efficiency,) and I've finally decided on a wall design for a new construction house I'm building. Curious as to what you think.

Location: CT (Zone 5)

1/2" Gypsum Board/Latex Paint
2x2 horizontal strapping with Roxul ComfortBoard 80 (1.5", R6)
2x6 wood studs 24"oc with Roxul R23
7/16" ZipSystem, taped appropriately
(2) layers 1.5" foil faced Polyiso, outside layer taped
1x3 strapping
Hardie Board siding

Effective R-value of both Roxul products: r23.42
Putting an R value of r5/in on the Polyiso: r15

Asked By Adam Nickerson | Jan 9 17
1 Answer

Fan efficacy and ERVs

what classification does a erv/hrv have if it doesn't have a ECM motor
it is not exempt from the efficacy requirement. so, does it a bathroom utility roon fan efficacy

Panasonic whisper comfort erv uses an ac motor .\
its fan efficacy is 40 cfm@ 0.1 esp/ 23 watts = 1.75 ?

Asked By Kevin Mick | Jan 11 17
1 Answer

3 ach50

Is there a way to know what the infiltration will be in a house after it passes the test?

If an exhaust ventilation system is used for ASHRAE 62.2 requirements, how do you know that sufficient makeup air will come in through cracks to compensate for what is exhausted?

Asked By Kevin Mick | Jan 11 17
2 Answers

Vented and unvented ceiling, Zip System, metal roofing, underlayment question

I am seeking some advice, and have been researching for quite a long time, but can't really seem to find the best answer for our situation.

Currently building New Construction in Climate Zone 5. Using ZIP System for the walls and roof.

In the center of the home, we have Unvented Cathedral Ceiling. We decided to use Unvented design, and insulate with Closed Cell Spray Foam.

On the two sides of the home, we have Vented Ceiling, with unconditioned attic space, insulating with fiberglass batts.

We plan on installing a metal roof.

Asked By Bridget Lamberson | Jan 10 17
4 Answers

Rigid foam, vapor barriers, and moisture issue avoidance

I am in process of picking 3" of EPS product for under my slab, around my stem wall and exterior wall CI. I have read through posts on GBA and articles on the Building Science website such as here that state the following is something to avoid, especially when using exterior rigid foam in your wall assembly:

Asked By Joshua Greisen | Jan 10 17
35 Answers

Another crawl space in the Northwest

Hello all, I have a 1150 sq ft rambler house in Fall City, Washington (near Seattle), zone marine 4c. I am currently in the process of redoing the crawl space. I have pulled the damaged and rodent infested insulation down, and removed the town vapor barrier. It seems I had some rodents that were digging past the foundation and getting into the crawlspace, ruining everything.

Asked By David Meyer | Nov 28 16
7 Answers

Flash and batt

I have been reading on the site about flash and batt but don't think I am "getting it". I live in south central Kentucky ( zone 4A) and have a woodworking shop built in the rear of a 1970 built garage. I have insulated the walls with fiberglass and have put tongue and groove pine over that.

I have put in a ridge beam so I could create an open space in there to work by removing the ceiling joists. Because the rafters are 2x6 I have also had to put in a couple intermediate beams to minimize any deflection in the roof.

Asked By Nickey Traughber | Jan 9 17
3 Answers

Sealing concrete foundation - foam insulation joints

Hello GBA Community - we poured concrete basement slabs about a week ago, with XPS installed vertically between the foundation walls and slab as a thermal break. The vapor barrier laps up between the wall and the XPS, though isn't taped to the wall. Should I use a sealant or tape to ensure a continuous air barrier, and if so, does anyone recommend a good product that will adhere to both the concrete and XPS?

Asked By Mike Dominic | Jan 9 17
3 Answers

Intus Eforte mounting brackets

Question for anyone with experience installing Intus Eforte windows: The brackets I received with my Intus windows seem too wide. There should be a pic attached showing a bracket sitting in front of the track it is supposed to twist into. Online images depict a different type of bracket. All mounting instructions depict brackets with teeth that are only slightly wider than the mounting track. Did I get a batch that belongs with a different window type or something?

Thanks for any help.

Asked By Jim Tyler | Jan 7 17
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