Q&A: A Forum for Green Building Experts and Beginners

[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!


14 Answers

Insulated slab detail "problem"

We are to build a Passive House in PA, and have "borrowed" a technique from another PH in Virginia, where part of a typical EPS under slab was substituted with a layer of perlite bags placed over just 4'' of EPS. I believe it also allowed us to reduce the slab thickness to 4'' (in the center).

In General questions | Asked By Lucyna de Barbaro | Aug 22 14
3 Answers

A layer of 1" XPS foam between fiberglass batts?

I live in MN and am working on a complete interior remodel. The exterior walls are 2"x6" w/ R19 fiberglass batt insulation, some with Kraft back & some with poly on the interior side. I would like to try & at least double the R value, but due to other design constraints would like to keep the additional interior intrusion to a minimum (exterior insulation is not possible).

In Energy efficiency and durability | Asked By Joshua Streblow | Sep 19 14
4 Answers

Thinking of going solar

I have reading alot about solar systems. I live in a 40' 5th wheel RV. Now This is what I was thinking of buying.....

6 - LG 305 watt solar panels ( 305 watt output each total 1830 watts ) ( around 75 amps output )
Magnum 5000 watt 24 volt inverter
Schneider (Xantrex) XW-MPPT-60-150V Charge Controller
4 - 6 volt 480ah Royal AGM batteries.
( Plus 3 - 30 amp fuse boxes and a junction box for the solar panels

My question is..............

I am Trying to figure out how many hours per will I be able to runs some devices on solar

In Green building techniques | Asked By Ron Davis | Sep 19 14
4 Answers

Would Tyvek on top of rafters and under roof sheeeting meet R806.4 for non-vented attics?

Wish to have a non-vented attic but desire blown insulation. It appears R806.4 does not allow this. Would Tyvek remove requirement for spray insulation against roof sheeting?

In Building Code Questions | Asked By Elmo Saunders | Sep 22 14
5 Answers

Help with basement design

Hello All,

I am working on refinishing a play room in the basement that was recently damaged from water coming through the slab because my gutter was not hooked into the corrugated pipe that takes water away. So I now I want to refinish a playroom for my 1 year old son in the basement, making sure the health and safety is the priority.

In Green building techniques | Asked By leonid grossman | Sep 21 14
3 Answers

Sealing gap between garage floor & drywall?

Hi:

I am trying to figure out whether & how to air seal the gap between my garage floor and drywall in my 12-year old three-story townhouse in zone 2a. The gap is generally 1/2" wide, however in many places it's less. The door shown in the photos leads to the first-floor of the house.

I think caulk (any particular kind?) is the answer, but wanted to check first.

Also curious - without performing a blower door test, how "bad" do you think this gap is from an air-sealing perspective?

Thanks,
Rob

In Green building techniques | Asked By Robert Hallenbeck | Sep 20 14
21 Answers

Liability insurance - what would that cover?

1. Does liability insurance cover issues related to removing improperly installed open-cell foam in an attic on the underside of a roof (i.e. all those horror stories about roof rot, or open-cell continually off-gassing or smelling weeks after it was installed, etc..)? Or is that a different type of insurance?

2. Should I specifically ask for the details in the Liability insurance to find out specifically what it covers, is that something contractors should be willing to share?

In General questions | Asked By George G | Sep 12 14
3 Answers

How do I fix the high air exchange in my straw-bale home?

Two years ago, I purchsed a straw bale home in Minnesota. When I closed the house was in poor shape and the exterior had to be rebuilt. Our first winter in the house was cool and drafty and we were spending a fair amount on heat. We did as much research as we could, but we have struggled to figure out how to fix and maintain our home.

In GBA Pro help | Asked By Eddy Wilbers | Sep 19 14
2 Answers

Reading “new to old”

Choice Martin in Q&A but then in blogs posts are not able to be new to old.

Easy fix to be done some day.

Thanks neighbor
Aj

In General questions | Asked By aj builder, Upstate NY Zone 6a | Sep 20 14
1 Answer

Fresh air intake filters

Hello,

I have the RecoupAerator ERV that I am in the process of getting installed. I have some sheet metal/duct people coming next week to give me estimates on installing the fresh air intake duct that will terminate thru an exterior soffit.

The RecoupAerator comes with MERV 12 filtration material inside, but I am wondering how to filter the air at the entry point into the fresh air intake duct. A simple insect screen there might still let small bugs and such into the the duct work where they will decompose.

In GBA Pro help | Asked By Venkat Y | Sep 20 14
Register for a free account and join the conversation


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