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1 Answer

Use regular OSB or Zip Wall OSB in conjunction with 2" XPS?

My wall plan consists of:
1- fiber cement siding
2- 3/4" air gap/ 1x4 firing strips
3- 15# felt (or possibly Tyvek housewrap) for general protection of the XPS
4- 2" rigid XPS with taped seams and caulked at butt joints
5- 7/16" OSB (possibly taped Zip Wall)
6- 2x4 24OC stud wall with mineral wool or fiberglass insulation
7- 1/2" drywall sealed at top and bottom and around device boxes and penetrations

In Green building techniques | Asked By Nathan Mogilski | May 22 15
6 Answers

Vinyl siding renovation


In Building Code Questions | Asked By Chris Felker | May 14 15
7 Answers

ADA sealant recommendation please

I'd like to air seal my baseboards to my drywall and concrete slab as part of an ADA.
What would you guys use to seal wood to acrylic paint & unfinished concrete?

I picked up some GE Silicone II Gutter & Flashing which says it sticks to wood and concrete, but was wondering if there was a better choice.

Thanks for your help,

In General questions | Asked By Richard Baumgarten | May 21 15
14 Answers

Guidance for designing and building a low-lifetime-cost home in North Texas

My wife and I want to build (or buy) an energy efficient home in North Texas sometime in the next 5 years. We are not strongly attached to certifications, R-value-comparison-contests, or even a particular style of home. We just want to build something cost-effective that we can live in for the next 40 years without having to maintain high-income jobs to pay for the utility bills and mortgage. I have been doing a lot of research, but I wanted to get some expert opinions to help guide me in the right direction.

In General questions | Asked By Chase Johnson | May 16 15
4 Answers

Does this kneewall plan make sense?

I am in a 1915 Bungalow with sloping ceilings in each of four closets upstairs. I haven't demo'd yet, but I can guess what I'll find in terms of open joist cavities, etc.

My original plan was to demo the knee wall and spray foam the ceiling slope all the way down to the eave, but I just can't afford spray foam. So my tentative plan is to create an unconditioned kneewall area that can be used for storage.

Something about my plan seems a bit off, I'm wondering if I'm missing something big here.

I drew up a plan, I hope it shows up as an attachment.


In Green building techniques | Asked By Adam Sick | May 20 15
10 Answers

Inductive cooktops and peak electric loads

I've been reading Dana's explanations at GBA that peak electric loads are the primary reason for the total electricity capacity required of any given utility. I understand that devices like electric point of use water heaters will easily drive higher those peak electricity requirements for the grid infrastructure. What about inductive cooktops? My understanding, which is limited, is that they have a much higher peak electricity requirement than standard electric ranges.

In Green products and materials | Asked By Eric Habegger | May 19 15
50 Answers

Affordable Cold Climate

Does any one care to "Challenge" Building America?


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

In Energy efficiency and durability | Asked By John Brooks N.Texas Zone 3a | Jan 12 11
39 Answers

3-D Networks, Premature Shingle Failure and Ant Farms

In Energy efficiency and durability | Asked By John Brooks | Dec 17 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?

In Energy efficiency and durability | Asked By Bob Irving | May 16 15
0 Answers

What new idea would you like to see pursued?

ORNL is running a competition for new ideas for building energy efficiency technologies. You can submit an idea or read and vote or comment on ideas that have been submitted. You have through the end of May to submit new ideas.


The leading idea right now is vacuum insulated panels that are plumbed to a central vacuum pump rather than being permanently sealed. Do you have a better idea than that?

Guidelines for ideas to submit, from their FAQ:
Innovative technical design ideas that are not yet prototyped

In General questions | Asked By Charlie Sullivan | May 19 15
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