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0 Answers

Can Larsen trusses be used for roofs?

My goal is to build a net zero home in a cold climate using the most cost efficient designs, methods and materials as possible. I'm in the design and planning stage at the moment and, to lower my costs, I plan to do as much of the work myself as reasonably possible and I'm hoping to use commonly available building materials whenever it makes sense. I'm currently in favour of using the Larsen truss system for a thick wall of dense packed cellulose but I'm wondering if that can be used for the roof as well. Has anyone seen this done before?

Asked By user-7037573 | Mar 20 18
1 Answer

Mini Split selection

I know this has been a well documented discussion on here. Yet here I am continuing it. I am close to making the final mini split unit selections for my house. I'm looking for advice on comparing three specific models. Let me know if I should be looking at others?

As background information, I am in Chicago and will be using two 1-Ton units to heat/cool my house + wood burning stove. House will have R 33 walls and R 50 roof. 2,100sf two story.

Asked By Seth Holmen | Mar 19 18
9 Answers

Thickness of Closed Cell Insulation in 2x4 Walls

I've built a 200 sq ft structure (tiny house on wheels, not inspected) with 2x4 walls and 2x6 rafters. I'm ready to insulate and have been planning on using closed cell spray foam for the whole thing to avoid moisture issues in the unvented cathedral ceiling. (I would love to use Roxul instead if it were an option). I don't have any can lights or skylights in the ceiling and only one penetration for the range hood.

My climate is 5A.

Asked By Mike Spooner | Mar 18 18
7 Answers

How much interior insulation would be safe

I have a building 2000sqft that I inherited in zone 6a that was built with 2x6walls 16"oc, and exterior 5/8" osb sheathing. It has house wrap(tyveck) over the sheathing then steel siding. The building is only a few yrs old but has been sitting unfinished in the inside. I want to build a 800 sqft living space into the building. The rest of the space will be a heated shop. The slab is insulated 4" xps with vapor barrier and it has foundation edge insulation 2" on the outside.

Asked By Smokey059 | Mar 19 18
7 Answers

Spray foam and electrical wiring

I recently had a conversation with a couple members of my family who are both electricians. In their continuing education class the instructor mentioned that the National Electric Code is monitoring the use of field applied spray foam and electrical wiring that becomes imbedded in the process. There have been failures in the wiring because of the heat that can build up in the covered wires, usually the problem is with constant and motor loads that operate at a higher ampacity.

Asked By Randy Williams | Mar 18 18
4 Answers

Sheathing data logger

I'm working on a house with brick veneer that was built in the ~1970's without weepholes or base flashing and the 1" vent cavity is almost entirely filled with mortar. I'd like to add a data logger in my walls to track the moisture content of the sheathing, for personal interest. It's two layers, 1/4" OSB sheathing over 1/2" fiberboard. I was wondering if anyone could point me towards some reasonably priced sensors & data loggers that would work for this. Something that wouldn't require a lot of user interaction to produce useful data as well.

Asked By Yupster | Mar 16 18
3 Answers

Proper WRB behind Boral Siding

We've been contacted to replace beveled cedar siding that is rotting on a 1939 story and a half. The existing wood windows have been well maintained and appear to be in good condition, and will not be removed during the project. The existing walls have little to no insulation that we know of.

Our plan is to remove the existing siding(following lead safe practices) insulate the wall with dense pack cellulose, install a WRB, reside with beveled Boral siding with mitered outside corners, and paint.

Asked By user-7040235 | Mar 19 18
0 Answers

Sealed gas see-through fireplace to outdoors

My wife loves a nice fire and wants a fireplace in our new home. One model we are considering is see-through, which would allow us to have the fireplace in the great room and the screened porch. This unit does not have a flue, since it exhausts to the outdoors from the top of the outside glass.

So, that would mean we have a metal connection from the outside to the inside with no thermal break. Although the glass is double paned (one inside and one outside), the 2 ft. separation pretty much negates any R-value.

Asked By Norman Bunn | Mar 19 18
6 Answers

Insulation and wall construction improvements for a groovy 70s partial-brick ranch


We live in Boulder, CO (climate zone 5). Our house is a 1970 ranch (with basement) that is "dipped in brick" as someone put it - the lower half of the walls have brick siding, and plywood board and batten siding from there on up. We're looking for suggestions on how to improve the insulation, and ultimately how to flash it.

Asked By Steve Sloan | Mar 7 18
11 Answers

How to Reduce High Energy Costs for Ductless Minisplits

Hello Martin,

I have the Mitsubishi H2i heat pumps as my primary heat source at my south east MA home. Seven indoor units [9 and 12K's] and two outdoor units [MXZ-3C30NAHZ, MXZ-4C36NAHZ]. The 2,400sqft 1980 contemporary style house has lots of [1st gen. Anderson double glazing and Pella single with interior "storm" panels] windows. The Pella's are actually [relative] better thermal performers. The wall insulation is typical of that generation, poor to fair. The attic has about 20" blown in insulation.

Asked By kazirode | Mar 16 18
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