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1 Answer

We have a garage/workshop that is occasionally heated

We have a garage/workshop that is occasionally heated with an overhead suite that is kept at 5 degrees Celsius. The ceiling of the suite is vapour-barriered and insulated.

The floor of the suite is about to be insulated. Should there be vapour barrier in the suite floor/workshop ceiling, and, if so, where?

We live in Hazelton, BC - near Smithers, BC.

Asked By Mike Tomlinson | Apr 29 17
8 Answers

Deep blown in cellulose for attic - questions

I have a few questions regarding deep (beyond R60) blown in cellulose for an attic. Cellulose is relatively cheap and I'd like to maximise my attic insulation without causing any other issues:

1. Several manufacturers of cellulose insulation have depth/R-value charts that stop at R60. Is there any practical reason for this, or is it just because most people don't bother going above R60?

2. Does compression above a certain depth negatively affect the performance of the insulation in any way? I.E. does your R-value/$ go down appreciably beyond a certain depth?

Asked By Lance Peters | Apr 24 17
4 Answers

Is 35 year-old under-attic-floor fiberglass insulation a health issue?

I'm asking about the formaldehyde issue. We'll be spray foaming the attic soon--R38 rafters and R21 gable walls. The contractor would like to remove as much of the under-floor fiberglass as possible to make it a better conditioned space. We're not so inclined, since our attic will really only be for storage, central AC maintenance, etc. and as long as the temps up there don't vary by more than a few degrees, the winter cold or summer heat outside shouldn't affect us in the floors below.

Asked By David Goldman | Apr 28 17
17 Answers

Remote thermostat for Fujitsu mini-split ?

I recently had a Fujitsu mini-split (AOU15RLS3H with ASU15RLS3) installed in a 24*36 foot room in Vermont. It is working well except that the temperature in the room not far from the unit is usually about 5 degrees below the setting on the remote. I have found two ways to get the temperature to the desired level: (1) Increase the setting on the remote or (2) set the fan not to automatic but to high. Neither of these solutions is ideal.

(Note that it is not in "economy" mode, the people sensor is off and the fan louver is pointing down.

Asked By David Martin | Oct 18 15
18 Answers

All-electric vs. natural gas in Zone 2

I'm building a house in Houston, Texas. It will probably be a 'pretty good' house - dense pack cellulose and exterior rigid foam installation with an encapsulated attic and targeting an ACH50 of <3 with an ERV system for ventilation. I will have a sizeable solar PV array on the roof - 6-8 kw so I have been debating whether to use natural gas as in my current house for multiple appliances or go all electric. Pros and Cons as I see them are:

Benefits all electric:
No standing monthly charge of $25 for gas since consumption is below threshold 9 months of year

Asked By user-6822325 | Apr 22 17
1 Answer

How Much Foam=A Thermal Break?

I am building in Western NC in Zone 4. In designing my "ideal wall", I would like to include a thermal break. Since code does not require any amount of exterior foam for this Zone, what would constitute "enough"? I plan to use Zip-R sheathing, and would like to keep it as thin as possible despite all of Huber's reassurances on it being an effective structural sheathing, even in the thicker versions. So, would the 1/2" be enough of a thermal break? 1"?

Asked By Kevin Spellman | Apr 28 17
11 Answers

Advice on my wall assembly

Hello, I'm getting ready to build a new home in western North Carolina. I would appreciate advice on my proposed wall assembly. 2x4 walls with huber's R-Zip 9.6 (2" thick overall) and coravent studi battens for a rain screen assembly. The idea is to end up with a wall assembly thickness so I can order windows for a 2x6 wall and have them work. So I end up with drywall(1/2") + 2x4 wall (3 1/2")+ Rzip board (2") + sturdi batten coravent (7/16") = 6 7/16". I was planning on closed cell foam in the 2x4 wall cavity.

Does this seem like a reasonable assembly?

Asked By Jeffrey Higel | Feb 8 17
2 Answers

Garage slab insulation

New construction, uninsulated, attached garage with the garage doors and one of the walls on the exterior, the other 2 walls are interior. The garage is on the same level as the basement which is insulated from the inside. I was thinking about adding a 4' wide strip of 4" EPS around the 2 exterior walls, and 2.5" EPS on the exterior garage wall (the garage doors will be insulated) to minimize the thermal bridging.

Asked By Jonathan Lawrence | Apr 28 17
6 Answers

1974 construction retrofit

A friend is looking to replace siding and windows on his 1974 house in climate 4 marine. The main floor and upstairs walls are 2x4 and the basement walls are 2x6. There is timber framing inside that I suspect bridges to the ext sheathing w/o any insulation. Where he has removed some of the vinyl siding, he found fiberboard sheathing (R1.32 stamped on it). I don't know what is under that. (The garage is just studs + fiberboard + siding). The gable walls have 3" overhangs and the roofing is 2 years old.

Asked By Mark Walker | Apr 25 17
6 Answers

Hip roof in Zone 6A

My client is a builder who has already completed the exterior siding and roofing of a new house in coastal Maine (zone 6A). The hipped roof and 2x6 walls have no exterior rigid insulation and no air space between cedar shingles and Typar. Walls: 2x6 with R-21 batt (John Mansfield), 1/2" CDX, Typar, cedar shingles. He plans to install shiplap hemlock paneling to the interior. Roof: Hip, 6 in 12 pitch, 2x10 rafters into (2) 11 7/8" hip rafters. Also has two dormers.

Assuming we go with an unvented assembly, how do we best achieve a vapor seal?

Asked By user-6825743 | Apr 22 17
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