Community: General questions

Q & A Instructions

[Click map to enlarge]

The 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

Looking for information on Apex Block. Is the company still in business?

Has anyone used Apex Block? Can you recommend an alternative, since I can get nowhere trying to contact them?

Asked By Jonathan Bankert | Apr 3 15
4 Answers

Tyvek and / or fanfold insulation under siding

I have a 1950s home and am adding new vinyl siding.

There is an option for Tyvek and / or fanfold insulation under the siding. My understanding is water will get through the siding so the main goal is to prevent water from reaching the sheathing. Tyvek seems to accomplish this. Is fanfold better or would both be better?

I have heavily insulated on the inside. I think the main potential problem with fanfold is to prevent possible moisture on the sheathing or between the studs. This is Iowa, hot humid summers with cold snowy winters.

Asked By Erich Riesenberg | Apr 2 15
2 Answers

Basement insulation with exterior wall waterproofing

I am a new home owner trying to answer a question that evokes different responses depending on which site I visit!! Or perhaps, I am just dumb!! Anyway here goes.

Asked By Chris Simmons | Apr 1 15
0 Answers

BuildingGreen publishes special news stories for April 1st

Here's a link to one of BuildingGreen's special news reports for April 1st:
Judge Robs Yost of Gold Medal in WUFI Modeling.


Asked By Martin Holladay | Apr 1 15
7 Answers

New home buyer — metal roof in Maine with no sheathing

Hello all,

I am a first time home buyer and looking into buying a new home. My wife and I have found the perfect home here in Maine, but found out today that the metal roof was attached directly to the perlins. I know typically there is supposed to be sheathing and a vapor barrier in between. I have found information on both sides of the argument, which have led me here. Is no sheathing adequate? How will it affect my energy use? and will it be a condensation issue? Is this ok for a cold climate here in Maine?

Asked By dimitrios maniatakos | Mar 28 15
10 Answers

Interior plywood for earthquake areas — can it replace a vapor retarder?

We are renovating a 1925 Pacific Northwest house, Everett WA, right on the coast. It is earthquake territory here. So it would be good to keep this house up through any quakes we may get, when it can be relatively easily done. We have double studded the kitchen wall now. Making it 8" deep. The north wall became 9" deep. Now we are in low need of any vapor retarder for our climate I understand, zone 4C. Interior air barrier never hurts BUT, and here is my question... Would interior plywood sheathing be a good choice to replace the air barrier, caulking the seams.

Asked By Jan Verschuren | Mar 29 15
4 Answers

GSHP comparison calculator?

I'm looking for an online tool where I can plug in some basic figures such as EER and COP and compare cost/benefit of two ground source heat pumps. Any ideas? Thanks

Asked By C. Maglio | Mar 28 15
5 Answers

Basement wall fire blocking material?

Martin's basement wall insulation article is a classic that I constantly refer to when planning my basement renovation. The main thing missing from the equation, however, is fire blocking. As I understand it, fire blocking generally needs to penetrate through any foam insulation all the way to the concrete. This presents issues with thermal bridging as well as compromising the air barrier and vapor retarder layers that the foam provides. What's the least bad choice? Mineral wool? Pressure treated lumber? Paperless gypsum board?

Asked By Nick Welch | Feb 6 15
3 Answers

JM Spider overhead

I was planning on using JM Spider on the underside of my structural roof deck. (There is a layer of peel and stick and 5.5" of polyiso foam board above the deck so no worries about vapor permeable insulation inside). The installer is having problems with getting the Spider to stick overhead. The installer says JM changed the fiber recently and they are having difficulties with some wall installations too. While they are working with JM, I was wondering:

Has anyone here had JM Spider installed overhead recently?

Asked By Eric West | Mar 27 15
6 Answers

Strapping material for rainscreen...plywood fir or spruce?

I'm ready to put the strapping on-top of my WRB, only I'm not sure what the best choice is.

I want a 3/8" gap, so cutting plywood strips is my only option (there is NO composite furring strips available in town...I called everywhere!)

I've got the option of 3/8 spruce with exterior glue, or 3/8 fur with exterior glue.

Does either have a lower tannin content that may deteriorate the WRB? Do I even have to worry about that? Should I back prime the strapping to avoid this?

I'm going to put cement board over the strapping then stone.


Asked By Mark Helmrich | Mar 16 15
Register for a free account and join the conversation

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