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5 Answers

Is a 1/4 gap in rainscreen enough?

Your advice and articles are topnotch. I wish I had been reading them before now. Thank you in advance for your help. I am renovating the east wall of my home in northern Vermont. For the past two months the wall has sat- OSB covered with Tyvek. I plan to side this wall with fiber-cement clapboards to match the rest of my house. The OSB is there and the windows are well-flashed, so I would rather not mess with them. I see that many sources recommend a 3/8 in. air gap in the rainscreen. If I do this I must reflash my windows. Do you think a 1/4 in. gap is adequate?

In Plans Review | Asked By Jeff Grogan | Jul 12 12
6 Answers

Frost-protected shallow foundation

I'm still not clear how a heated building frost-protected shallow foundation (FPSF) and unheated building FPSF differ in design and theory. I'm about to try to build myself a small home/shop and I don't know how far I'll be able to get before the dead of winter here in Vermont. The cold doom and a potentially unfinished home puts me in the unheated classification for a month or however long it takes me to get insulated but back to heated when I'm finished.

In Green building techniques | Asked By David Burke | Jul 12 12
3 Answers

Too much southern exposure?

We have been looking for a passive solar/contemporary type house without much luck. We are considering this house but I’m concerned there may be not enough overhangs.

House was custom designed in 1980

Original Owners lived there 22 years

The house is exactly positioned for southern expose

Much of the house has a very thoughtful design with the exception of overhangs on the south side
Current owners live there 9 years and are showing electric bills of average 200 month

The whole house is electric

In PassivHaus | Asked By Robert Metelsky | Jul 14 12
10 Answers

Maine built pre-1800 post & beam no insulation

you go that right. ZERO insulation. Walls are plaster/lath and plaster/ split boards. Lath work came in around 1800? so the older part (built before 1750) has no lath-- just very wide boards split to accept plaster.

In General questions | Asked By oldhouse Inn | Jun 2 12
15 Answers

Soffit framing after air barrier is complete

I have decided to use a Larsen truss wall detail on a small house that we are building. I was intrigued by an air-sealing detail I heard mentioned, perhaps on this site. The idea was to frame the house and most of the roof but to add the eave and rake overhangs after the building has been made airtight. Does anyone know of a drawing of this sort of detail?

In General questions | Asked By erik olofsson | Jul 10 12
2 Answers

Who provides plans/specs/design help to owner?

I love all the content here. Since I'm designing our new house right now, and trying to pick a builder, I'm near the point that I have to start providing plans/specs. Here's the issue; how do I find the person to draw plans/specify all these complex iissues? Especially concerned with solar PV/mini-split locations, or solar thermal vs heat pump water heater questions. LOcation is Calif zone 11, ie mild winter, hot summer, great solar incidence. So who and how do I find a designer/plan drawer/specifier?

In General questions | Asked By Michael McKinley | Jul 15 12
2 Answers

Heat pumps

What heat pump is best or more cost-effective and most energy-efficient? Direct earth contact or air circulation? Why? Where can I find the best info on these systems? Thanks.

In Mechanicals | Asked By Joe Ross | Jul 15 12
3 Answers

Are retrofit LED lamps for can lights a good alternative for new construction?

Retrofit LED and conventional can will cost about $85 apiece, dedicated LED cans are around $175. What are the advantages/disadvantages?

In Green products and materials | Asked By Terry Herschberger | Jul 15 12
66 Answers

The SunRise Home.

I have been cruising this presentation by Thorsten Chlupp and wanted to see if anyone who might have actualy seen it, might have some comments.
http://passivehouse.us/passiveHouse/2010_Passive_House_Conference_Presen...

In General questions | Asked By Lucas Durand - 7A | Feb 24 11
4 Answers

What is the best way to hold a double studded wall on a >R20 foundation with exterior insulation (ie rigid foam)?

We are aiming toward PassiveHaus standard and plan a double studded wall with dense pack cellulose for the main envelope sitting on top of a foundation preferably with deep exterior insulation (ie 4" rigid foam). The plan would be for the exterior 2x4 (or SIP) to be the roof loading wall (large snow load in northern NH). How do we best insulate the basement/ foundation to allow structural integrity and load and avoid the wall sitting inside of the foundation insulation?

In Green building techniques | Asked By Phil Lawson | Jul 12 12
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