Community: Energy efficiency and durability

[Click map to enlarge]

Please register for a free account or sign in to ask and answer green building questions.

The usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration:
Under the box labeled "More explanation," look for the words "File attachments."
Click that, and you should be able to attach a photo.

Thanks for joining the conversation!


1 Answer

Is there an energy efficiency penalty for an oversized dehumidifier?

If i buy one that is oversized for my basement it will presumably run fewer hours a day at higher wattage, is there any penalty or lower effectiveness on this?
The one i am considering is 1.85L/kWh energy star rated compared to another 1.85L/kWh unit.

Asked By Alan B | May 22 15
22 Answers

Ductless minisplits - Zone 5 - with basement

Hello folks, this is my first post at GBA so bear (beer) with me. My son and I are building a new for my wife and I to live our days out in, two story bungalow style with a full basement under.

Some stats;

Exterior Walls - 2x6 16" on center with 2' XPS on exterior, wet blown cellulose in the bays. 3/4" rain screen furring over foam, cedar lap siding. R19 in the bays + R10 = R29+

Ceiling - 2x10 sealed vault flash (core bond) + batt - R49

Basement Walls 8' (6.5" below grade/ 1.5" above) with 1.5" polyiso + R13 Batt in 2.4 stud wall over foam - R22

Basement Slab - 2" XPS

Asked By Brian Martin | May 16 15
12 Answers

Interesting SIP alternative

Came across this site EZ Sip (http://structuralinsulatedpanels.com/).

My original retirement house plan was the standard 2x6 wall framing, Roxul batt interior, with 1/2" ply exterior wall then 2" of Roxul then the furring strips with appropriate siding.

After seeing this concept and the associated savings in construction time, I am now in a bit of a quandary. Method does seem to meet interior and exterior insulation values, as well as issues of stud bleed through. Having ply on out side resolves potential accumulation of moisture due to dew point issues.

Asked By William Oldaker | May 19 15
50 Answers

Affordable Cold Climate

Does any one care to "Challenge" Building America?

http://www.buildingscience.com/documents/case-studies/cs-ma-westford-hfh

Is there a "greener" and user friendly way to provide
An Affordable 3 bedoom 2 bath Home for a Cold Climate?

Optional Hint ... the 2nd floor can be re-arranged

Asked By John Brooks N.Texas Zone 3a | Jan 12 11
7 Answers

Small super insulated house - grid tied or off grid?

Where is the $$ line today between grid tied and off grid? I’m talking to a retired nurse with a limited budget who wants to build an 800 SF, super insulated net zero home on a lot (in NH) which requires a long driveway (and therefore an expensive connection to the grid) . She will have low electrical plug loads. Does the Tesla Powerwall battery influence the decision?

Asked By Bob Irving | May 16 15
16 Answers

Budget concern: Better to buy the R-10 windows with less-great walls?

A budget crunch forces some tough decisions. Most of the bidders prefer using 2x6s instead of the double stud wall, and using American R-2.5 to 3 windows over the European R-10 ones. My general knowledge is that heat always moves to warm up what is cold, therefore keeping our R-10 windows in the design seems like the place to spend our money. This would mean backing down to an overall R-22 wall (2x6s 24" oc, exterior 1.5" Zip System and another 1" of rigid insulation, well sealed batt or rock wool in the cavity).

Asked By Will Gerstmyer | May 13 15
2 Answers

What's the most efficient way to run a dehumidifier?

I have tried everything but short of a DER i can't reduce the humidity load of the basement so i have little choice to bring in a dehumidifier.
The one i am getting is oversized according to online sources, 500sqft needs a small dehumidifier but i am getting a 70 pint energy star rated frigidaire (long story). It uses 746W and pulls 70 pints a day at 1.85L/kWh.

Asked By Alan B | May 17 15
3 Answers

Do minimum thickness of foam rules still apply for the partition wall between an insulated attached garage and the house?

Climate zone 6 location near Green Bay, wi. Partition wall is advanced frame 2x6 wall construction with planned 2 lb density blown fiberglass. I would like to use 1" foil faced polyiso on the cold side of the wall to limit thermal bridging and also tape the panels for a primary air barrier.

Asked By Rick Van Handel | May 16 15
16 Answers

Non-typical insulation of barn / garage

I live in Interior Alaska Zone 7/8. I have a rather large barn pole barn that needs to be insulated so it can be heated. Since it is rural there is no code but i want to ensure that i do not do something that damages or ruins the building over the long term with that said money is not unlimited. The space is intended to be heated to just above freezing 35 to 40 typical with the ability to warm even more during use. Not a business just personal use during the week.

Barn size is 50x60 with 14 foot walls.

Asked By James Williamson | Mar 22 15
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!