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

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

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

If you want to post a question, 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

I have two specific questions regarding efficient home-run plumbing design

My wife and I are currently working with a local design/builder on a set of plans for a small home in Silver City, NM (4B). The main bathroom, mechanical room and kitchen are all grouped together on the 850 square ft main floor. A second bathroom, located directly above the main bathroom, is planned for the 550 square ft loft. The wall assembly will be 2*6, dense pack cellulose, 1 inch of EPS exterior the sheathing, and fiber-cement siding.

Asked By Aaron Beckworth | Feb 17 17
33 Answers

Humidity

While I was on the subject originally regarding adding central air to my gas furnace, someone was talking about humidity levels in the winter and how dry you feel at home.
I just realized and was told that whole house humidifiers only work/operate anyway, when the furnace is actually running. Makes sense.
in my opinion, and having a hydrometer to prove it, whole house humidifiers are a waste of money, period.

Asked By Dave Mac | Feb 15 17
2 Answers

What do you do when you can't find duct leakage issue?

Conducted an audit today on a manufactured home with a rectangular duct board system in the belly. Duct leakage testing resulted in NO reading at 25 pascals. We crawled under the entire home following the trunk lines and found no visible signs of broken or disconnected ducts that could explain such high leakage. Has anyone out there ever ran into a situation like this? If so what did you do?

Asked By Benjamin Barker | Feb 16 17
14 Answers

Kingspan Kooltherm - R-8/in?

Recently got sent a sample and some information on a new 'premium' rigid foam Kingspan is trying to market in the US after making it in Europe for quite a while. A little googling and this appears to be some sort of phenolic foam, maybe. Some of the claims in the literature have me scratching my head:

-R-8/inch. Seems awfully high for rigid foam. They claim this is from an ASTM C 518 test but the rep wouldn't send me the actual report.

Asked By Chris B | Feb 16 17
8 Answers

Mini-Split & Generator vs Wood Stove

Hi,

I'm about to build a house about 8 miles outside of Brockport, NY (near Rochester). The lot has electricity but no gas. I would like to heat my house off mini-splits, and I'm currently having a Manual J done to determine feasibility. The footprint of the house almost guarantees that I will need more than one small mini-split rather than one central unit. I plan on having a backup generator.

Here's the question: Should I put in a wood stove for backup heat, or simply put a small minisplit on the generator?

Asked By John Ranson | Feb 17 17
0 Answers

Do pellet stoves generate much creosote?

Having lived in a house with wood heat for over 40 years, I've fairly familiar with the ways in which wood stoves can contribute to creosote formation in chimneys and stovepipes. However, I'm not very familiar with pellet stoves.

A friend recently wondered about creosote formation in a chimney connected to a pellet stove. So I'd like to hear from owners of pellet stoves: Does your stove lead to more or less creosote formation than a typical wood stove?

-- Martin Holladay

Asked By Martin Holladay | Feb 17 17
13 Answers

How to fix my unvented cathedral ceiling roof assembly?

We tried to build a house with a fairly tight envelope based on reading I could find. Well, apparently I messed up, so really want some advise before I mess things up more.
House is in central Missouri( zone 4, but real close to 5). Small, 750 sf but with an open loft making it about 940sf. Sealed Concrete slab as the finished floor, and new construction ( under roof in may but moved in The next January). Red metal roof and one side of that faces north..
Walls are 2x4 and we used open cell foam with 1/4" foam inside the studs as an air ( not vapor) barrier.

Asked By Brenda K | Feb 16 17
6 Answers

Zip System R-Sheathing

Quick question about Zip System R-Sheathing.

The concept of a REMOTE wall, where exterior insulation is used to ensure that the structural sheathing stays warm (and thus dry), makes perfect sense to me.

The Zip System R-Sheathing is a compelling product because it saves several steps by installing all the necessary wall components in one go.

HOWEVER, from the pictures on their website, it looks like the Zip System R-Sheathing has the WRB on the outside, followed by the sheathing, followed by the insulation. So, doesn't this mean that the sheathing is cold?

How does that work?

Asked By Matt Culik | Feb 16 17
2 Answers

Rainscreen with gapped panels

Hello Again GBA'ers

We have a design for a ventilated rain screen ventilated with mixed cladding materials. This will be exterior to 6" of foam board insulation. One of the materials is Equitone, and the manufacturer recommendation calls for 3/8" gap between panels, they supply a butyl tape to face the furring strips, both to provide a dark color on the reveal and to provide a moisture barrier on the face of the wood furring strip. The panels are very long, and there will be long horizontal gaps.

Two questions:

Asked By Gerald Pehl | Feb 16 17
14 Answers

Noise from PEX/PVC drain pipes

Hello,
We are at the stage of starting the framing for the new construction home in Pittsburgh. It is also a Passive House duplex. Our architect specified cast iron for domestic water drainage pipes (from shower and toilet, etc.), mostly on the account that these result in most quiet interior. For delivery of the water within the house, PEX is planned. Then we heard that iron pipes are more susceptible to clogging. Is some compromise, where pipes close to dining/living room are cast iron, and PEX elsewhere an OK option?

Asked By Lucyna de Barbaro | Dec 6 14
Register for a free account and join the conversation


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