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5 Answers

Polyurethane foam vs. Icynene foam: What's best for subfloor insulation?

I have a house that is brick veneer and the front section has the polished timber floors.
The sub floor area was not properly ventilated and we had some mould issues. Since then we have had vent’s installed and a sub floor fan under one of the rooms.
However it is a clay soil that the house is suspended on, there are still a some mould spurs on the soil. The air under one room is always quiet damp.

I was wondering if product is more suitable for this type of application ….does notabsorb the moisture in the air and will mould grow on it ??

Asked By Rheems I | Jul 25 16
7 Answers

Off-grid weather station to measure build site conditions

I've purchased vacant land in hilly terrain and will be building a residence and workshop next summer.
I'd like to setup a solar or battery powered weather station to learn more about the microclimate.

Knowing, e.g., typical temperature and humidity swings on the site will help me answer questions like: "how much insulation does the workshop need to prevent condensation / rust on tools?"

Does anyone know of an off-the-shelf battery or solar powered weather station that can measure temperature, humidity, and wind speed?

Asked By Kevin Lynagh | Jul 26 16
1 Answer

Minisplit retrofit in Climate Zone 2

I'm trying to figure out how to use a minisplit system on a retrofit project. I got a quote from an HVAC company (recommended by the equipment rep), but some of their opinions don't make sense...which brings me here today.

The HVAC company proposed 4 zones with a 3 Ton compressor outside:
1 ducted 9k unit in attic, serving Guest Bath, Guest Bed, and Office
1 ducted 9k unit in attic serving Master Bed and Bath
1 9k ductless serving kitchen
1 9k ductless serving living

Asked By Green Heron | Jul 26 16
3 Answers

ERV-Minisplit combo vs. Magic Box

We are conducting a deep energy retrofit on our two unit building (each unit 1,500 sf) in Chicago (zone 5a). I am pretty much done with the first floor and chose the ERV-Minisplit combo to primarily address our ventilation needs, cooling needs and summer dehumidification. And it appears to work well (Recoupaerator and one 12,000 Btu Fujitsu Minisplit): Winter time humidity around 40%, summer time humidity around 55%.

Asked By Marcus de la fleur | Jul 26 16
13 Answers

Exterior walls to meet code without gypsum?

Hello,

Maybe this has been discussed here. Feel free to link me to other threads that I haven't seen if this is fully covered elsewhere.

I'm not a fan of drywall. A quick rundown with no real surprises: it used to be cheaper; now it's not. It also takes plenty of work and more money to make it look nice. It's heavy but also very breakable. Even when you don't break it, it's messy. Etc, etc. I *am* a fan of 3/4 plywood, which is less breakable, more durable, and looks nice.

Asked By Minneapolis Disaster, 6B | Jul 22 16
62 Answers

Questioning my logic...GSHP, ASHP, radiant?

I'm in the planning/almost ready to break ground stage of a new home and I'm beginning to question my sanity when it comes to figuring out the right approach for heating & cooling.

The home is:
North end of Climate Zone 5
Main Floor: 1700 sq ft + 1000 sq ft garage, vaulted ceilings through much of it
2nd Floor: 1100 sq ft (2 bedrooms, 2 baths, living room) primarily over the garage
Basement: 1700 sq ft, partial walkout + 1000 sq ft shop under the garage (separated from the rest of the basement)

Walls: R30+ (2x6, 2" XPS outside, 2lb SPF for sealing + 1/2lb SPF for cavity fill)

Asked By Dave De C | Jul 16 16
4 Answers

Fiberglass batts in a cathedral ceiling?

Hi Martin,
I've been reading the GBA web site and have subscribed to the Fine Homebuilding magazine for several years but this is my first venture into the "green expert" arena. I could ask much but will try to narrow my questions to the two below.
My wife and I are building a small, hopefully energy efficient week-end/retirement home located approximately 50 miles east of Erie PA. Though the maps indicate Zone 5, having grown up there and experienced the winter lake effects, I'm considering it Zone 6.

Asked By Michael Watson | Jul 26 16
10 Answers

Bowed gable-end truss

Today we got 18/19 trusses set and somewhat braced, more to go on bracing.

The problem we ran into is that the gable and would meet the wall in the middle, but both ends were off the walls. The walls are straight and flat.

I pulled the gable down and snapped a chalk line along the bottom of the bottom chord, and found that the center was lower than the ends by a good 3/4".

Having never set a pre-buiilt gable truss, I would think that it would be nearly impossible to load the top chord enough during installation to push the bow out.

Asked By Mike M | Jul 24 16
8 Answers

1903 home, first time with central air, lots of questions about insulating, ductwork, etc

Hello! Grab a cup of coffee and hopefully you will have a little insight on this! Thank you!!!!!!!!!!!!!!

I have an early 1900s 2 story victorian home 2200 sq ft, currently getting a new roof next month, and had to remove the old insulation on the attic floor that was outdated in roof preparation (in april). Blown in insulation was added to all exterior walls, as well as a thin sheet of foam fiberglass insulation, prior to installing vinyl siding over the wood siding about 25 years ago. Also storm windows to cover the old windows.

Asked By John Friend | Jul 25 16
6 Answers

Looking for design software recommendations

Hi -

I'm a new member and I'm looking for recommendations for relatively easy-to-use design software (I did try searching the site but didn't find anything discussing that). My first task will be a simple floor plan so I can ask the good folks here for advice on placing mini-splits. Further down the road, I'd like to be able to draw out details for roof and wall assemblies for the retrofits I hope to do. Any then maybe a tiny house (or at least a tiny shed) in the future.

Asked By Nickolas Van Kleeck | Jul 23 16
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