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4 Answers

Half inch plywood battens for rain screen?

My contractor put up the first three quarter inch 1x4s today and there isn't quite enough room for my siding around the windows and doors. If I had another quarter inch I'd be fine. My question is will I have a strong enough wall if I use 1x4 half inch 5 ply fir plywood battens over inch and a half roxul using the heco topix therm screws made for inch and a half foam board? I would use three inch siding nails that would go through the battens and into the studs a half inch.

Asked By Cragged | Jan 22 18
11 Answers

Eave detail

Hello again! For the most part I'm pretty confident in this wall/eave detail, but I'm open to criticism.

My main concern is the long term viability of the "exposed" membrane above the IJoists. I haven't called it out specifically, but I'm assuming it's a fancy vapor item WRB of some kind.

Along the lines of a recent post here regarding longevity... is it foolish to leave the WRB in the open here? The intent is to create a cold roof.

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Jan 21 18
7 Answers

Foundation detail

I've been developing my "poor man's thermomass" for some while and hope to get some feedback on a few points. First of all, after looking at many many many other foundation details with exterior insulation, I'm still not confident that this arrangement of insulation sufficiently creates a thermal break. Most discussion is about insulated basements but this is slab on grade.

Below 4" slab is 10" recycled glass Poraver beads. This is on top of compacted gravel. At the Endeavor Center, they put 6mil poly below poraver. I'm worried this created a "bathtub" situation.

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Jan 21 18
6 Answers

Insulation with best life expectancy and low embodied energy?

I'm researching insulation options. I want to keep embodied energy down, but also want to have something with a life expectancy of centuries, not decades. Although I've mostly nixed SIPs (PU) because of it's high embodied energy, if it lasts centuries while other insulation materials last decades, then should it be considered? I've also been finding different opinions on the life expectancy of SIPs. Some people say 300 years, others say 50-100.

Asked By Mike AbiEzzi | Jan 19 18
3 Answers

Options for reducing ladybug infestation?

Is there a good "green" way to get rid of ladybugs?

We have hundreds in the walls in our house. Unfortunately it is not possible to completely seal this old house, so we have them crawling into the attic, into the bathroom, and now they are crawling all over the closed cell foam. I wonder if they eat sawdust, or maybe the operation of power tools in the attic creates vibrations that make them come out of their crevices.

Asked By rich cowen | Jan 21 18
6 Answers

Perfect Wall assembly

Hello All,

I'm building a small cabin in the mountains of North Carolina later this year (Beech Mountain). Elevation is at about 5,000 feet and the climate can actually be pretty brutal for the southeast in the winter (Zone 5 Climate). Average January high is around 35 and low around 15, but temps can get 10 to 20 below zero on occasion.

I'm planning on building an envelope based on Joe Lstiburek's "Perfect Wall" theory.

My wall will be constructed as follows (from exterior to interior):
- HardiPlank or Galvalume Siding (haven't decided yet) for exterior cladding

Asked By Rodrob15 | Jan 18 18
9 Answers

Insulating a pole barn

Hi. I am interested in building a small (20'x20') eco friendly pole building as a "tiny house". I like the idea of a pole building because it avoids the use of concrete for the foundation. I plan on using perlite bags beneath an earthen floor as the "sub-slab" insulation. For the walls and ceilings, I would like to use cellulose. I have not been able to find any details online for appropriately insulating and air sealing pole buildings. What resources I have found generally ignore thermal bridging entirely, for instance.

I would like to achieve R-40 walls and an R-60 roof.

Asked By Steven Gubkin | Sep 30 15
5 Answers

Climate Zone 3C: Crawl space, roof, and wall systems review

I'm in the design phase of a remodel of an existing 2 story house, CZ3 coastal, zip code 95062. The scope includes a new foundation and gutting the house with some interior walls moving, but for the most part keeping the existing exterior shape and roof line. Goal is a high performing house (well insulated, air sealed, mechanically ventilated, high IAQ and minimal heating and cooling loads). I've attached a line drawing of the shell for reference.

Asked By Phil Boutelle | Jan 9 18
6 Answers

Basement / crawlspace insulation

Basement of an addition has two levels. Most of the space is at normal height but about a third is raised to only about three feet high. Needed to do this because of the nearby ISDS. Energy auditors are recommending rigid foam on these "crawlspace walls" and not all the walls. Does this make sense?


Asked By Jonathan Blaney | Jan 16 18
1 Answer

Insulation the basement joist parallel with basement wall

There is a lot of information on how to insulate basement joists, but it's hard to find information about insulating the last basement joist that runs parallel with the foundation wall on the gable ends. Does the basement joist along this side of the house also require rigid foam or spray foam insulation?

Asked By Andrew G | Jan 14 18
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