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3 Answers

Low-maintenance siding for Vermont

I am considering changing the majority of the siding (3000-4000 of 5000 sq ft) from weather atlantic cedar rainscreen design to a low maintenance pre-finished siding to save money on a project. Anyone have experience with these and/or recommend other options?

Certainteed Icon prefinished 30 year 16' - https://www.amerhart.com/certainteed-icon-composite-siding/
Boral Truexterior prefinished 15 year 16' - http://www.bostoncedar.com/boral-truexterior-pre-painted-siding/
Everlast 12' - prefinished lifetime - https://www.everlastsiding.com

In Green products and materials | Asked By J M | May 15 18
9 Answers

Exterior spray foam insulation over OSB?

Getting ready to building a home and couldn't find much info on this except in commercial applications. Had a meeting with the insulation contractor (in business since 1976) and explained to him that I wanted an airtight home with good insulation, I mentioned ZIP-R with blown in cellulose or loose fill fiberglass.

In Energy efficiency and durability | Asked By Roger V. | May 13 18
2 Answers

Alternative ventilation for small homes in cold climates

The Cold Climate Housing Research Center (CCHRC, www.cchrc.org) is researching alternative ventilation options that could be better suited for small homes (under 1500 sq ft. typically with less than 50 CFM required ventilation) in Alaska.

In Mechanicals | Asked By CCHRC | May 14 18
7 Answers

Thermally broken

I am planning to use 2" of rigid foam to the edges of my rafters on my cathedral ceiling to get me 11" of cavity and a thermal break. I can use polyiso or EPS for the break. The polyiso will be a little higher R-value, but costs more (not a big deal since we are just doing the edges). We plan to vent the ceiling and dense pack with cellulose. Some questions come to mind:

In Energy efficiency and durability | Asked By Norman Bunn | May 13 18
15 Answers

Using Reclaimed Fiberglass (?) Faced Polyiso

I have access to some 3.5" reclaimed polyiso that I believe has a fiberglass facing on each side of the board. At least, I think its fiberglass. The best way to describe the facing is it kind of reminds me of landscape fabric.

My intention was to use the foam as sheathing on the walls of the house I'm building. I am just down the road from Urbana, IL (Climate Zone 5A....but feeling a bit more like 4A at times).

My wall assembly (from interior to exterior) is as follows.....
- drywall
- 2x6 with mineral wool batts (R-23)
- ZIP sheathing
- 3.5" polyiso (~R-22)

In General questions | Asked By Robert Kohaus | Nov 18 13
7 Answers

Interior air barrier in walls

Hello again

Thanks to help from those here last year I have built a holiday home cabin/garage close to Vancouver, Canada, (Zone 4C I recall). The exterior is complete and my project this summer is to complete the interior.

Firstly, this 'outbuilding' is not considered by the inspector to be a habitable building, so many 'code' rules don't apply. I believe this means we do not need to install an interior vapour barrier as per the norm in the area. Moreover, my reading on here suggests I should not need an interior vapour barrier anyway. I'm I correct in this assumption?

In General questions | Asked By Quinn Sievewright | May 13 18
5 Answers

Alternative to SIP roof?

Hi. I'm building a cabin in Wa State and the designer has spec'd a SIP roof. I have two concerns...

- First, how to finish the visible underside of the SIPs? The SIP company (Premier) apparently only offers a secondary ACX plywood lamination, which I don't care for. Is there a common method for producing a finished ceiling with SIPs?

In Green building techniques | Asked By user-7070878 | May 13 18
1 Answer

Effloresence on concrete ceiling

Hello. I have a client with a basement that has a concrete ceiling section about 10'x35'. There is a brick walkway above it and it has leaked into the basement cieling causing efflorescence and that drops all over what they have stored in the basement.
Though someone sprayed Moxie on the exterior surface of the bricks, client reports they still have leaks in basement cieling that cause lines of efflorescence, which, again, falls on their pocessions stored below.

In GBA Pro help | Asked By RSBme | May 14 18
14 Answers

What is the point of Passivhaus certification?

I see this come up often in cost analysis discussions, but I fail to see how certification can be anything other than a sunk cost. Unless I have a completely wrong perception of the process.

Are there direct subsidies in some places?

If certification is done after the house has been built, how can it help you build a better house?

If certification starts with designing, why would passivhaus certifiers be any better then other people who measure air leakage and calculate necessary insulation etc?

In PassivHaus | Asked By Davor Radman | May 12 18
6 Answers

Improvements in high-R phenolic foam since the disastrous 1980s

So I have been reading about the closed-cell phenolic and noticed the recent blog describing the use R-8/in Kingspan Kooltherm phenolic foam board in a retrofit.

The unique ability of these phenolic foams to achieve high R-values upwards of R-8 per inch seems to be established in testing and experience. However...

In Green products and materials | Asked By Aaron Birkland | May 6 18
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