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4 Answers

Possiblity of moisture within the layers of polyiso?

I need to meet code (R38- zone 5- on a cathedral ceiling) and would like to do this as cheaply as possible. The exterior of my roof assembly looks like: 3/4 ply, ice and water shield, asphalt shingles. The proposed interior would look like: 1 inch vent (ripped 1x1 w/ 1/4 ply), roxul (r 15), and 3 1/2 inches polyiso rigid insulation. The 3 inches of polyiso would be cut to fit in between rafters while the other 1/2 inch would go over the strapping to give me my thermal break as well as vapor barrier.

In General questions | Asked By derck sturgeon | Aug 25 12
6 Answers

What would our best heating option be?

We live in Juneau, Alaska and our main heating options are electricity from hydro power (14 cent a kilowatt) or oil (diesel #2; $5 a gallon). We have an old oil fired hot water base board heating system we would like to replace with an energy efficient system. We can get a $10,000 rebate from AK Home energy rebate program on renewable energy sources (Air and ground source) and we are also looking at the federal tax credit. And either an air or ground source system reduces our electricity cost by about 1/2 for specialized rates.

In Energy efficiency and durability | Asked By julie bednarski | Aug 21 12
1 Answer

Following Argue's super-insulated retrofit plan (circa 1981)

After seeing a reference to Robert Argue's 1981 Super-Insulated Retrofit book on this site I went out and purchased a lightly used copy online. I am now in need of some advice...following Argue's plan of wrapping the outside of your home with polyethylene sheeting and building curtain walls filled with horizontal and vertical layers of unfaced fiberglass sounds great..but is there a better combination of materials (roxul in place of fiberglass, ice and water in place of polyethylene?) to achieve the same level of insulation and air tightness?

In Green building techniques | Asked By Chris Bachand | Aug 24 12
4 Answers

Whole House or Point of Entry Water Filters?

I'm looking to add water filtration to my home, and am trying to figure out whether a whole house water filter, or individual point of entry water filters (ie, at the sink) would be better. It might be easier to just have the one whole house filter installed, but I am wondering if I will ultimately end up filtering a lot of water that doesn't need to be filtered, as opposed to just putting filters at the sinks were water is actually used for drinking, brushing teeth, etc.

In General questions | Asked By Brian Jackson | Aug 19 12
4 Answers

Dark-coloured roof..?

my client wants her standing seam roof to be dark brown. will this, at least partly, sabotage my building's energy efficiency? or is it a non-factor...

In General questions | Asked By erik olofsson | Aug 23 12
2 Answers

What is a good way to attach insulation to earthen walls?

I'm currently looking at building a small home with a focus on using local materials. This is certainly not a new concept in the green building world. Local materials for me (in Golden, B.C, Canada) are wood, earth and stone. There is a Roxul manufacturing plant in southern B.C as well.
My thoughts are to build Compressed Earth Block walls, wood-framed roof and floor systems, and probably a rubble-trench foundation with an earthen floor or concrete slab-on-grade. Many details to work out.

It has been shown here

In Green building techniques | Asked By Nick Furfaro | Feb 24 12
5 Answers

Rigid insulation with OSB in rafters?

So, you guys have been a big help so far. I have another question, spurred by what looks like a good deal on craigslist for new polyiso insulation.

The catch is that this insulation has OSB on one side and paper on the other. I am interested in putting it up within my catherdral ceiling rafters and under the rafters.

How bad would this be to put up? If it is not good, are their any cheap workarounds? The price is half the foil faced at the big box store.

There would be a 1" space between the insulation and the roof, but it technically isn't vented (1950s 1.5 story ranch).

In General questions | Asked By NIkki Horz | Aug 20 12
5 Answers

Does anyone have any experience or hear of magnesium oxide structural insulated planels?

About to begin work with local devleloper who is going to build homes using magenesium oxide SIPS. Claims that magnesium oxide panels are the "dry wall" of China. Have reviewed mock up w/ out staff architect and the material looks sound enough. The concept is sound, but has anyone ever heard of magnesium oxide panels or used them? Anyreferences would be helpful. Thanks.

In GBA Pro help | Asked By mike keesee | Jan 26 12
2 Answers

My signature...

How can i edit my 'signature' so that it gives all my zone info?

In General questions | Asked By erik olofsson | Aug 23 12
5 Answers

Off or On Grid?

We are planning to build a 2 story with basement 28x34' near Passive House in northern NH. It will cost > $25K to bring in power at the expense of cutting that will worsen the aesthetics (ie the swath....).
Our present electrical use without being careful in a similar sized home heated with oil ranges from 6KWhr (July) to 15 kWhr (Jan) per day. We would pay 16-17c/KW on grid and only get a 4c premium if we hooked in....

In PassivHaus | Asked By Phil Lawson | Aug 23 12
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