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2 Answers

Stucco over SIPs: rainscreen necessary? Installation tips?

We'd like to have a stucco finish over SIPs, but area stucco contractors seem stumped by the SIPs.

I'm wondering what's required:

vapor barrier?
rainscreen construction?

Is acrylic stucco or a lime-based stucco better?


In Green building techniques | Asked By Claire Anderson | Sep 1 09
2 Answers

Mechanicals for a well insulated house

I am looking for the most cost effective heating,ventilation,hot water strategies for a medium sized house with r-30 walls, r -60 cielings in western Ma.

Which ends up being more economical, on demand gas hot water or solar with gas backup?

How cost effective is heat recovery?

I have heard of a unit that combines boiler, hot air,ventilation,hot water in one unit, has anyone used one?

Are there books or articles I should read?

In Energy efficiency and durability | Asked By will goodwin | Sep 3 09
2 Answers

Temporary attic insulation

I have recently purchased a home that has minimal attic insulation (4" cellulose). I would like to add either batt or rigid foam insulation to increase the R-factor. The issue is that 3 yrs (Minnesota winters) from now I plan on adding a 2nd floor, and would at that time need to pull up the added insulation, which would be reused on the addition. There is easy access to the entire attic, and I would like to take advantage of the tax credits now. Any recommendations on which product to use, or is this a waste of my time?

In Energy efficiency and durability | Asked By Corey Kluever | Aug 12 09
2 Answers

Which SIPs for roof: 10 1/2 in. vs. 12 1/2 in. for performance?

We've been quoted an additional $1,460 to "upgrade" to 12.5-inch roof SIPs and are wondering if the additional investment is "worth it."

I've always heard that the more insulation you have in your ceiling/attic, the better, but I'm wondering if that $1,450 would be better spent on other energy-efficiency measures.


In Energy efficiency and durability | Asked By Claire Anderson | Sep 1 09
0 Answers

Is it better to continue a SIPs roof past the bearing wall and use that as the overhang or just extend the splines and frame it?

We're in the process of building an all-SIPs home, but have received a bid that runs the roof panels to the bearing wall. The roof splines will be carried out to the spec'd overhang length, so that framing lumber can be attached to construct the overhangs.

The quote for extending the SIPs panels to the overhang length is an additional $4,000.

I'm wondering what folks think is the best strategy, structurally: Carry the SIPs out or use the spines to attach framing to construct the overhangs?


In Green building techniques | Asked By Claire Anderson | Sep 1 09
1 Answer

Extending gables to make overhang for foam

In a few weeks I start the reroofing and while reroofing I will extend out the gable ends of two roofs so that I have enough overhang to fit 4" of XP on the outside of the walls below.

One extension will be limited to 5 or 6", and the other can be anything I like (probably 16").

There are two ways that I know of to extend the gable:
Both are illustrated here:

1) Barge rafters (which attach blocks to the end rafter and build out).
2) Lookout rafters (which notch the existing end rafter to fit a 2"x6" or 2"x4" to extend out the roof)

In Green building techniques | Asked By Mark Bartosik | Aug 31 09
7 Answers

Attaching siding to houses with exterior foam insulation

How difficult is it to attach siding, trim and windows to a house that has 2" of rigid foam insulation on the outside? Some people recommend a layer of furring on the outside of the foam, it that adequate to hold siding on? Do building inspectors allow the ommision of a poly vapor barrier on the inside with this system?

In Green building techniques | Asked By William Goodwin | Aug 30 09
2 Answers

I am looking for a good solution to damp basement floors in old homes

I am looking for a good solution to damp basement floors in old homes that have no vapor barrier below the slab, and which are being super-insulated and air sealed.

In Green products and materials | Asked By Matt Berges | Aug 30 09
4 Answers

Cross use of building materials

While re-roofing I'm going to have to take the vinyl siding off a dormer to lap flashing up the wall as high as the snow line. While I am at it I plan to re-flash 3 windows on the dormer.

From the roofing work I will have about 5 sq of Grace Tri-flex breathable membrane spare, and some Grace Ice & Water or Grace Ultra.

Q> Should I use left over Grace Tri-Flex as an alternative to house wrap (e.g. Tyvek) on the dormer?
Q> I presume that I should remove the tar paper first no mater what I use?

In Green building techniques | Asked By Mark Bartosik | Aug 30 09
0 Answers

Are there any non-sodium, low- or no-water waste ways to remove minerals like calcium from water supplies?

Conventional water softeners add salt to wastewater and use plenty of water to rinse systems. Can filtration or ionization or some other method minimize mineral build-up in hot water systems and fixtures?

In General questions | Asked By Stephen Colley | Aug 31 09
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