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1 Answer

Hi everyone,

I am about to begin residing my house. I was wondering what everyone's input was on where the housewrap should go in this case.

House is located in North NJ (zone 5-6 border).

-Framing is 2x4
-Fiberglass Batt Insulation R-13 in studs
-Polyiso 1.5" (fiberglass faced polyisocyanurate)(permeability <1.0) less than 1.0 according to a buildingscience article.

Design & Construction Option 1:
-Vinyl Siding
-Polyiso 1.5" (permeability <1.0)
-Housewrap (Tyvek or Dow)(Drainage Plane)
-1/2" Plywood
-2x4 Studs (Fiberglass Batt Insulation R13)

In Green building techniques | Asked By Dan Nospa | Sep 24 11
9 Answers

First off, I have read about every post, blog, and entry made on here about triple pane windows, have talked with the companies, received bids, etc. So with that being said...

On paper, they do not seem to make any sense now matter how I look at it. I have ran numbers in multiple programs from as simple as RESFEN to high end stuff in my Revit MEP and other modeling programs. I am happy to say all of my loads and energy costs are very similar from the free programs to the high end however.

In Energy efficiency and durability | Asked By Jesse Lizer | Sep 22 11
3 Answers

Can I use taped 1-2" exterior XPS as my sheathing and drainage plane (with no OSB sheathing, racking taken care of with other bracing methods) and full cavity high density spray foam (2x6)?

In zone 6/7 where I am (cold) my exterior sheathing should be very thick (3"+) assuming OSB sheathing to avoid condensation issues on the interior surface of the OSB. BUT if the OSB is left off as planned and the spray foam and XPS essentially become one unit (really 6 or 7" of total foam) am I OK on the condensation issue?


In Energy efficiency and durability | Asked By Andrew Snowdon | Sep 22 11
8 Answers

I know it won't be cheap, but I want to shift my energy use from oil to Solar PV.

Currently I have a hot water system and baseboard hot water heating.
I plan on installing a Solar array and so I would like to convert to an all electric design.

Do I take everything out and install electric baseboard heaters and an electric Hot water heater?

Or would it make more sense to use my current system and just find a way to heat the water with the PV array instead of with oil?


In Mechanicals | Asked By chris eaton | Sep 20 11
4 Answers

My home in Santa Rosa, CA (zone 3c), has a stucco exterior and uninsulated 2x4 walls. I was hoping to make gradual improvements to the envelope as my budget allows. However, a termite problem has accelerated my schedule, at least in the bathroom, which I have now stripped down to the studs, inside and out. I would like the exterior finish to stay uniform, so I thought a good option for increasing insulation would be to use some kind of batt in the walls with 2" or so of rigid polyiso on the interior.

In Green building techniques | Asked By Mark Morley | Sep 22 11
1 Answer

In particular, pex piping for radiant floor heating needs.

In Energy efficiency and durability | Asked By DANIEL LAJOIE | Sep 21 11
1 Answer

I'm looking to install new vinyl siding. The house was built in the late 40's and has currently has two layers of siding on it. The top layer is cedar board and batten. The second layer is clapboard, but I'm not sure of the material type.

I've met with three contractors. One wants to remove both layers while the other two were planning to side over both of the existing layers removing only the batten. The last contractor went back and forth before deciding that siding over both layers would be ok.

In General questions | Asked By Chris Maida | Sep 21 11
4 Answers

I live in Minneapolis Minnesota. Is there any problem with installing a polyethylene barrier in the ceiling? The insulation installer wants to use it to hold up the blow-in cellulose before the drywall goes up. I was planning on just using a vapor retarding primer/paint. One concern I have is that If I ever do have a leak in the roof I won't know about it because the poly sheeting will block the water from reaching the drywall.

In Energy efficiency and durability | Asked By David Adams | Sep 21 11
3 Answers

We were reviewing some details in our office the other day and I noticed we had been showing backer rod and sealant between a "flanged" window and siding/trim. It get me thinking about all the articles I have seen in JLC, FHB, etc and never recall seeing the backer rod. Even Martin's recent details in FHB don't show it. Then I checked several window manufacturers and Andersen was the only one I found so far that says backer rod and sealant. Of course, they do say to leave 1/4" gap, which to my knowledge is the smallest backer rod available.

In General questions | Asked By Glen M | Sep 20 11
1 Answer

Referencing GBA diagram "Plan detail // cement board lap siding // 1 1/2" rigid insulation" as a starting point, If I am attaching the furring thru the foam to the studs, what is the fastening requirements, specifically screw size, spacing and stud penetration depth? Thanks

In Building Code Questions | Asked By Jim Orasky | Sep 21 11
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