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17 Answers

Still Grinding - Uninsulated basement and minisplit problems

It's been about 1 year and 10 months since I started building my house and I'm still grinding. Doing the board and batten siding mixed with cedar is taking some time. Especially since I'm doing it mostly by myself!

In Energy efficiency and durability | Asked By Jimmy Nguyen | May 9 17
8 Answers

Opinions on my exterior options

I have posted a few times regarding my situation and have been provided a lot of great information from GBA. I have not really been able to figure out what would be the best option for my situation. So i thought i would try and summarize and hope the minds here can point me in the right direction.

Current house climate zone 6
2x6 16"oc fiberglass batt
Wood siding
2.64 ACH

The siding is being ripped off as it is failing in multiple places

Inspect sheathing/framing for water issues, replace as needed
Tape seams of plywood
Add Tyvek or similar wrb

In Energy efficiency and durability | Asked By Jeremy Archer | May 15 17
6 Answers

New addition with closed cell in rafters on top of current roof?

We live in a coastal town in MA and just started an addition on a 1940's house. Currently have a simple sloped roof with blown in cellulose on floor. Two gable vents on either end and a few roof vents that we put in as well. The addition will be two stories and be a 'roof on roof' per the architect with a cut out to allow for electric/HVAC to be brought in from the current roof (HVAC is in this unconditioned space currently). The plan is to re-roof the entire house when the addition is put on. The addition will be unvented and have spray foam in rafters.

In Energy efficiency and durability | Asked By eoren1 | May 16 17
13 Answers

ERV help

Here are the details on our house build:
1792 square feet plus full basement, zone 5. 3 bedroom, 2 bath. 4 people in the house

In General questions | Asked By Michael Brackett | May 15 17
6 Answers

My mom lives in a converted barn

Hi. I hope someone can help me. My mom lives in a converted barn. The air conditioner and oil burner are in the basement which in on the ground floor in the back and underground in the front. It's on a slope. She lives upstairs. In the summer, the central...

The basement is on a slab. I don't know how much insulation is in the walls or attic. Oh, and the attic is only in the center of the apt. The lower part of the ceiling is a cathedral ceiling. I think the whole apt is about 800 square feet, if that helps. Thanks again!

In General questions | Asked By Caren Villano | May 15 17
4 Answers

Air exchanger ducting strategy

We are in Minnesota (Zone 6a). The home is an "L" shaped, 2200 sq/ft single level, slab on grade. Our floor plan is attached. We will be using a mini split for primary heating and cooling and electric baseboard to satisfy the code.

In Mechanicals | Asked By Scott K | May 15 17
6 Answers

Passivhaus total energy usage standard

One of the Passivhaus standards is that total energy usage including appliances cannot exceed 11.1 kwh per sq. ft. per year. If I have a 2800 square foot house, then if my total kwh usage is under 31,080 (11.1 x 2800) that is pretty good right?

Seems like that's a pretty low bar. Or am I misinterpreting?


In PassivHaus | Asked By Jimmy Nguyen | May 11 17
17 Answers

Georgia Power's PV policy

We are under Georgia Power which does not allow net metering. Instead, I think we currently get reimbursed 4.2 cents/kwh for what our PV system produces, which is about 1/3 of what GA Power charges us for their power. Complicating matters is that during the summer, when our west-facing array is producing significant output, we are on GA Power's "Nights & Weekends" program which charges 20 cents/kwh on afternoons and 5 cents/kwh at all other times.

In Mechanicals | Asked By charles CAMPBELL | May 12 17
10 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?

In Energy efficiency and durability | Asked By Lance Peters | Apr 24 17
15 Answers

Final design: Roof, walls, and floor

So getting final details of a new build in Zone 6 (Osaca, ON) Hopefully pretty good house , that will be Net-Zero.
Any comments or suggestions before I finalize this? Thanks !!!

Roof setup:
Standing seam metal roof
Blueskin self-adhered membrane
5/8 plywood
2” air gap
attic truss with raised heal
24” minimum blown in cellulose
1/2” drywall
latex paint

Wall setup Outside to Inside:
Vinyl Board and Batten Siding
1x4 furring strips mounted horizontal 12” OC
2 layers of 2” Silverboard EPS taped seams
Blueskin VP100 ,maybe something else?

In Green building techniques | Asked By Dave B | Apr 4 17
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