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22 Answers

Mitsubishi mini split behaving very differently with external thermostat vs. without

I am able to monitor my home's electricity use and I always thought it was a little weird that my Mitsubishi FE18NA heat pump seemed to constantly be spiking up and down, considering that the whole idea of the inverter-driven compressor is that it can run smooth and steady... fast forward to yesterday when I received my MHK1 thermostat and hooked it up. Suddenly, the power usage was steady as a rock.

In Mechanicals | Asked By Nick Welch | Jan 6 15
5 Answers

What is the best way to manage moisture in a cinder block building in a hot, humid climate?

Having rebuilt my tiny bargeboard shotgun house in New Orleans, I now wish to turn my attention to the garage. Unlike the house itself, which has a pier foundation and a wood frame, the garage is a cinder block building on a concrete slab.

In Green building techniques | Asked By Shannon Holman | Mar 20 15
14 Answers

Bug screen for rainscreen strapping...how wide to cut?

I'm a rookie with this. First time building a rainscreen. I've got my WBB on the house and would like to apply my 3/8 strapping to create and airgap.

I picked up a few hundred feet of 4' bug screen and I will first apply a layer top and bottom, then my strapping and then staple the bug screen on-top of the strapping making the air gap, hopefully, bug free.

In General questions | Asked By Mark Helmrich | Mar 18 15
6 Answers

Small addition

I am in the early design phase of a small (12'x20') addition for a client in climate zone 5 and am just looking for suggestions as to the best new construction insulation & air sealing details to use.

It will be wood frame construction with a crawl space and a gable roof with vaulted ceilings inside.

I am leaning toward the zip wall sheathing system on walls & roof deck with a rainscreen on top and fiberglass batts in the 2x6 stud bay. Is the zip wall roof sheathing of sufficient thickness to allow me to build an unvented roof without having to spray 2-part foam on the underside?

In Energy efficiency and durability | Asked By Jason Schatz | Mar 24 15
2 Answers

OSB for rainscreen furring?

Hey all - I'm going to be residing my single story house this summer (climate Marine 4c - Seattle). The walls look like this (inside to out):

Gypsum > 2x4 cavity (to be filled with dense-pack cellulose) > 1x8-1x10 shiplap sheathing > 15/30 lb Felt, taped > 1" polyiso > OSB furring (with core-a-vent sv-5) > hardie plank/cedar shingles.

In Energy efficiency and durability | Asked By Mateo K. | Mar 24 15
8 Answers

Dryer vent in air-tight Passive House

I am building a house in the Seattle area to Passive House standards. After spending countless hours sealing every crack, seam and penetration to achieve under 0.6 ACH, creating a 4 inch diameter hole in my air barrier pains me. I've looked into condensing dryers that are used in some European Passive Houses, but they seam to take much longer to dry and use lots of water. Since I will be installing a vented dryer (unless someone can come up with another solution), are there ways to make the dryer wall vent more air-tight when the dryer is not in use?

In PassivHaus | Asked By Gerald Blycker | Nov 21 14
6 Answers

Filtration and humidification with mini-split systems

I have a customer with allergies. Her existing GFA furnace has a high efficiency filter and a humidifier.

In the new (air sealed and super insulated) home we are designing for her, we are planning to use Fujitsu mini-splits for heating and cooling and a Honeywell ERV for ventilation. Specs for these units indicate a washable filter but no MERV rating.

In Mechanicals | Asked By Terry Herschberger | Mar 23 15
3 Answers

Thicker walls

I live in Minnesota. I'm remodeling an older home with full 2x4 studs. On the outside there is a layer of 1 inch buffalo board and 1 inch foil covered foam.
Is it worth the time and money to add wood strips to the 2x4's to make them 2x6's on the inside and go from a R-15 to R-19 or 21 insulation or add 2 inch certifoam to the outside or should I just leave it alone with 2x4 walls and R-15?

Thank you

In General questions | Asked By Scott Neels | Mar 22 15
3 Answers

Foil tape inside duct?

I have several heat registers that I can access the duct from the inside only on, a few as far as 2 feet into them. Some just have seems, one has a good 1 inch gap on one side. (I'll try to hammer that together from the inside.)

Anyway, I've read that mastic can dry out on the inside of ducts, but have read conflicting suggestions about foil tape. I have this tape right now, should it work on the seems inside the duct, in the last 2 or so feet before the register?

http://www.homedepot.com/p/Nashua-Tape-1-89-in-x-50-yd-322-Multi-Purpose...

In Mechanicals | Asked By Jeremy M | Mar 23 15
2 Answers

thicker walls -- [Not really a new thread]

The interior is gutted to the studs. Was going to replace old isolation with R-15. Will be residing in the future. Vinal is brittle and we are replacing all windows. Doing all the work myself so it's just what I think I'm worth.
Thank you

In General questions | Asked By Scott Neels | Mar 23 15
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