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6 Answers

Gable access to attic?

The house we are designing will have an attic with roof trusses. No ductwork in it, just lots of insulation. The only time I think it would need to be accessed would be to check for or repair roof leaks. Properly air sealing and insulating an indoor attic access hatch seems somewhat expensive.

Does anyone access their attic through an exterior door in the gable wall - where it would need to be weatherproof, but not air-tight or insulated? Not sure if that is feasible or practical.

Asked By Debra | Sep 14 17
22 Answers

Solar assisted Heat pump vs normal air/ground source ? Home in Nova Scotia

I have been researching different heating techniques for a new build in Nova Scotia

4 acres of land
On the ocean (Ocean side is NE- SE)
2 story home + Walkout basement
Main level: 1,600 sqft + 2 car garage (730sq ft)
Upstairs level: 1,050 sqft 3 bedrooms/2 bathrooms (550 sq ft less than main level due to open ceiling)+ loft on garage approx 600 sqft (potential 4th bedroom and den) 450
Walkout Basement : 1,600 sqft (10 foot ceilings) with windows on eastern and southern side

Asked By snarbs | Sep 14 17
15 Answers

A few air-sealing questions (at the sheathing stage).


My plywood sheathing with be my exterior air barrier and my housewrap will not be (not taping the bottom of the wrap).

I have a few questions for some tips and advice for you. The question number corresponds with the picture number

1) What is the best way to airseal my outdoor panel box here in this picture?

2) The cutout around my bathroom exhaust fan has a lot of room around it. Will it be sufficient to just tape around or should I stuff some sort of insulation in the gap first?

Asked By Tommy87 | Aug 5 17
8 Answers

HVAC - Continuous Operation or More Zoning

Should I run a ducted heat pump system with ECM motors continuously or go with a more zoned approach with the units coming on and off as needed?

Asked By Kevin Camfield | Sep 13 17
3 Answers

Turning off/setting back ductless minisplits, kwh, efficiency, and more

So I talked to an LG engineer today (hint: if you have questions about minisplit performance, don't call tech support, find the number to a local manufacturer and ask to talk to their engineer).

My 4 ton LG LMU48HV condenser can cool down to 14,400 btus. At that minimum, the system will use around 900 watts. This was actually verified by my Efergy Elite monitor, which showed that during 82 degree outside temperature, 3 of my indoor units were on, and it showed a pretty constant energy use of 900 watts for the 8 hours that it was on (2 pm - 10 pm).

Asked By Jimmy Nguyen | Sep 15 17
4 Answers

Air-sealing a metal chimney

Hello GBA community, I have a question about air-sealing an ICC Excel chimney servicing a woodstove in Manitoba, Canada:

Asked By Benjamin Pries | Sep 12 17
4 Answers

Door flashing detail

We are in Minnesota (Zone 6a). 2200 sq/ft single level (9' walls), slab on grade.

Is a recess in the slab the preferred method for pan flashing a slab? I have several innie doors, 1 outie doors and 1 sliding patio door. How deep should these be? 1/2"?

Asked By Scott K | Sep 14 17
1 Answer

Price for replacing roof

We had a couple of leaks through our tiled roof. A roofing (limited) company would not give a quote before starting the job, saying they needed to see what the roofing felt etc was like and needed to removed areas of tiles to find out.

They quoted us £15,000 to do the job, but they had already removed several areas of tiles and started replacing battens before giving me the price, so I was not able to dispute it at that stage. I negotiated the price down to £14,250, and they made me sign a "quotation" at this price.

Asked By Jonathan-123 | Sep 15 17
4 Answers

4x8 Sheathing on 9' wall

We are in Minnesota (Zone 6a). 2200 sq/ft single level (9' walls), slab on grade.

I was planning on doing 4 x 9 sheets of plywood on the exterior of my double stud wall. The 9' sheets are about double the price of 4 x 8 sheets. What is the best strategy for applying 4 x 8 sheets on a 9' wall? Staggered horizontally? Lot of extra seams to tape...and is it counter productive to even consider 4 x 8's if I have those extra seam that aren't backed by a stud. I REALLY don't want to pay $35 a sheet for 4 x 9 cdx.

Asked By Scott K | Sep 14 17
10 Answers

Air-source heat pump for heating, cooling, and domestic hot water

We are working on a net zero project here in Dauphin, MB (Western Manitoba) and are interested in reducing our annual electrical usage (thereby minimizing the size of our required PV system to achieve net zero 'status'). I have been encouraged by our energy modeller to consider a cold climate air source heat pump for space heating and cooling. I am seeking to know if a practical solution exists to use air source heat pump technology for space heating, cooling AND domestic hot water with a single outdoor unit.

The annual usage is estimated as follows:

Space Heating 2100 kWh

Asked By Eric Bjornson | Aug 31 17
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