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14 Answers

We are trying to maximize wall assembly R-value: Very cold climate in CO

New home construction: 2x6 ext wall with 2" of closed cell spray foam with the additional 3.5" of cellulose or fiberglass batt. I was thinking of going with Dow's SIS panel (1" R5.5), but I am reading from one of Robert Riversong's comments that the impermeability of the SIS panel (Polyiso) is a bad idea for our climate.

In Energy efficiency and durability | Asked By ryan evanczyk | Mar 27 11
2 Answers

Anyone know of a dense pack cellulose course offered near CT?

I'm a remodeler in southeastern CT. I will be building my own house within the next year, and I'm looking for a resource to learn how to install dense pack cellulose.

In GBA Pro help | Asked By Samuel Kilpatrick | Jan 25 13
8 Answers

Is a standard 'Home Slicker - 6 mm' for under wood shingle siding adequate for Cape Cod, MA area ?

There are two types of slickers by Benjamin Obdyk .... the 6mm is perfect for what Iwant to do, but there is also a 10mm which is required by code in certain parts of Canada. Is there a 10mm code requirement for rainscreens in MA ?

In Green products and materials | Asked By CUDJOE KUBUAFOR | Jan 23 13
3 Answers

Deep energy retrofit strategies for uninsulated brick home in Phoenix

I'm looking to perform a deep energy retrofit on my 1947 brick home in Phoenix, AZ, and was hoping to get some feedback from the forum about the most cost-effective and beneficial strategies. The exterior walls are exposed double-wythe brick with 3/4" plaster on the interior. The windows are the original leaky, single-pane, steel casements. The attic is vented with R-38 on the ceiling, and the majority of the ductwork is exposed to the high attic temps.

In Energy efficiency and durability | Asked By Nathan Morey | Jan 25 13
2 Answers

Any value to ceiling insulation when constructing a conditioned attic?

I'm ready for insulation in my retrofit project, zone 3 in North Carolina. The building has 1 1/2" of poly foam on the exterior 2x6 walls, which will be filled with cellulose. The roof deck has 3" of poly, the underside will have 6" of open cell foam sprayed onto the underside of the roof deck. My question: The insulation contractor has suggested that I may want to add 6" of cellulose blown in at the ceiling level. I can see some value here preventing sound from migrating between rooms (common walls will be insulated for sound as well), but is there any thermal benefit to be gained here?

In General questions | Asked By Bill Savoie | Jan 25 13
1 Answer

I have heard a lot of talk about our homes of today not outlasting our 30 year mortgage. I would love to hear more about this topic.

Code built house will not last as long as mortgage.

In Energy efficiency and durability | Asked By terry herndon | Jan 25 13
4 Answers

International Residential Code

Is the International Residential Code available online, free, anywhere? If not, is there anything equivalent available -- at least good-enough for a DIY builder?

Looking at Abebooks I see that I can get 2000 and maybe 2003 or 2006 versions for less than $15.


How much different are these older versions compared to the latest version? How helpful is it to a DIY builder to have access to the International Energy Conservation Code?

In General questions | Asked By Jack Woolfe | Jan 24 13
1 Answer

Flash and Batt foam thickness

I'm in NJ climate zone 5 and have a project with an installed falsh and batt with 1" closed cell foam and Roxul batt in wood framing. I usually spec 2"+ but would like to avoid ripping everything apart and spraying more foam. Is there a chart/rule-of-thumb anywhere showing wtih of foam based on climate zone averages or any specific data to justify thickness besides doing a calc? This seems like a case where it would probably be ok but with a small chance for a big problem??

In Energy efficiency and durability | Asked By Michael Margulies | Jan 25 13
0 Answers

Seeking framer familiar with exterior rigid insulation in Southeast MI

My wife and I are building a new home in Royal Oak, MI with anticipated May start. Our general contractor is having difficulty finding a framer familiar with the installation of exterior rigid foam. Any referrals would be greatly appreciated.

Our planned wall assembly:
2x6 framing
2-3" of polyiso (2 layers with seams staggered)
WRB - tyvek or similar
Furring strips

In General questions | Asked By Troy Stevenson | Jan 24 13
0 Answers

Commercial windows in residential application


I have a residential house project starting this spring in Breckenridge, Colorado (8900 elevation). Our house has a contemporary design and would like to put commercial windows in the majority of the house. Local building codes have adopted the 2006 energy code and require .35 U value for the fenestration opening. I have several questions regarding this issue.

In Energy efficiency and durability | Asked By Bret Bonenberger | Jan 24 13
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