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1 Answer

Relative value of air sealing at exterior sheathing

I am trying to understand the relative value of air sealing at the sheathing. To do this lets consider cost as the benchmark. I realize that there is value beyond cost but this is an easily quantifiable benchmark and the one that seems most resonate with my clients.

Asked By Hugh Stearns | Jul 1 15
10 Answers

It's 2015 and they still build like this...

Brand new build going up in Phoenix, AZ. What you see is completely 100% framed and ready for stucco. The missing OSB sheathing is done on purpose. They do "open framing" and only use sheathing where required. The rest is open 2x4 framing.

They will stuff R-13 batts within the 2x4 walls, staple on some building paper and then put 1" of rigid EPS on the outside and use conventional stucco to finish it off.

A recent blower door test on a home like this showed 15 air changes per hour.

ALL of the duct work and air handlers are installed in the 150F unconditioned attic.

Asked By Peter L | Jul 1 15
63 Answers

Attic hot after closed cell spray

Finished attic with 4 foot knee wall , duct located in knee wall to support 2 floor,extremely hot, BASF spray tite 2 inches with spray foam wraped around rafter in knee wall but with Sheetrock on ceiling just 2 in foam In cavity . Suggestions to handle heat issue. Richmond Virginia all attic seal very well thinking heat coming from rafters under Sheetrock. Thermal convection coming from rafters. Worked done in the winter, crawl space also done, house built 1994 colonial 2 story with garage with room above with dormer. Also in crawl space does it really need supply vent and return vent

Asked By Mark hippchen | Jun 27 15
3 Answers

Can a feature be added to e-mail on a reply?

If i want to follow a conversation, I have to come back to it and sometimes it ends up on the second or third page. It would be very convenient that once I reply to someone's question, I get an e-mail when it gets replied to by someone else.

Asked By Alan B | Jul 1 15
17 Answers

Foundation capillary break & waterproofing

My wife and I are building a small home (First Day Cottage) on a full foundation with a walkout on the downhill end. I read about having a capillary break between the footing and foundation wall and it makes sense to me. When I asked the concrete contractor about it he said he's never done it (though he did remember one other customer who asked about it a couple years back). I get the impression they won't leave me much time to do it myself between pours.

Asked By Martin Frank | Jun 30 15
2 Answers

Older home (1950s) smells of mildew...

I purchased a home in late 2009 and have been trying to get rid of a heavy mildew odor. Last week I discovered the seller had put vinyl siding over two layers of other siding. Underneath the vinyl was a layer of extremely damaged Boise Cascade panel siding. It was crumbling and had large holes in multiple places (no house wrap). Behind the holes I discovered clear plastic sheeting and underneath that was cedar lap siding. I continued on down to the Buffalo board that was somewhat warped and had a strong mildew odor.

Asked By Terri Gerhart | Jul 1 15
5 Answers

Air sealing exterior walls in a benign climate

Hello Martin,
I am removing and replacing the siding on an old Victorian located in Berkeley, CA which I believe is climate zone 3. After stripping off the old layers of siding, we will insulate, install plywood sheathing, (nailed at 4 at eh edges and 6 in the field for seismic stiffness), and then a drainable house wrap and fiber cement siding.

Asked By Craig McCaleb | Jun 20 15
2 Answers

Inground gutters

A few years back I came across an article in Finehomebuiling about inground gutters. Has anyone tried this solution to wet basements? Does it work?

Asked By Daniel Cimaglio | Jul 1 15
14 Answers

Foam over a concrete floor

I plan 4 - 6 inches of EPS under the slab and now am considering an inch of either EPS or XPS on top with 5/8 or 3/4 tongue and groove plywood or OSB to provide a nicer floor to walk on as well as a warmer floor in the walk out basement. I think this will make it easier to attach partition walls and tile in the bathroom and hardwoods in the sunroom.
Question. .. Is this a good idea, and do I glue the foam (EPs or xps) to the concrete and the sheeting to the foam or leave it free floating?
Any gotchas in this?

Asked By tim brown | Jun 29 15
2 Answers

Choosing a solar (PV) system

Hi, I am completely new to solar and considering proposals from a couple of contractors.

One is proposing a 3.1 kW system of (9) 345W SunPower panels with a SunnyBoy inverter located on a south facing roof.

The other is proposing a 4.2 kW system of (14) 305 kW LG panels with a Fronius Primo 5.0-1 inverter, with panels located on a south facing roof plus on a basically flat roof adjacent to it.

Asked By Nancy Hartman | Jun 30 15
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