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2 Answers

Housewrap placement on a "wrap and strap" job

Using XPS on my "wrap and strap," and wondering if the housewrap needs to be installed directly against the XPS or can be installed on the straps directly under the siding.

In Green building techniques | Asked By Daniel F. Vellone | Jul 14 17
2 Answers

Seal and insulate before considering venting?

If you have an older cape and it has both heat and moisture issues on the upper floor and in the attic and you have limited time and resources, would you first do your best at air sealing and insulating the house, and then evaluate whether those problems go away before considering venting the house?

In Energy efficiency and durability | Asked By Jeff Towson | Jul 14 17
16 Answers

Basement as cold/heat source

Hi All,

My home has about 1313 sq. ft. living/dining/kitchen area (open floor plan) with about 723 sq. ft. of bedrooms on the side. Similar layout in the finished/conditioned full basement. The house (2012 ICF/EIFS construction) has been cooled and heated with a 3.5 ton AC and 15 kW heatstrips respectively.

The air handler is in a mechanical room in the basement, supplying to registers in the floor of first floor and the ceiling of the basement with returns high up on the walls on first floor and near the floor on the walls in the basement.

In Energy efficiency and durability | Asked By Venkat Y | Jul 10 17
5 Answers

Well-known Habitat for Humanity volunteer suffers medical issues

At work at a Habitat for Humanity construction site in Winnipeg, Manitoba -- reportedly "cutting wood" -- former U.S. president Jimmy Carter collapsed in the hot sun due to dehydration. He was taken to a hospital as a precaution.

Jimmy Carter, recently diagnosed with cancer, is 92. He's a role model.

Here's a link to the article: Jimmy Carter Treated for Dehydration at Canadian Hospital.

The photo below [from the NY Times] shows him at work on a Habitat project in Edmonton on Tuesday of this week.

In General questions | Asked By Martin Holladay | Jul 14 17
6 Answers

Improving the building envelope for existing bump-outs

We are in the process of addressing repairing some structural framing issues (dry rot caused by bulk water intrusion due to missing flashing) in our 110-year old home, a two-story balloon-framed foursquare in Manhattan, KS (climate zone 4).

In General questions | Asked By User-6885249 | Jul 13 17
1 Answer

Modeling of HERS Score parameters

Why are HERS score parameters for GSHPs modeled with the "equipment performance data from the nameplate" while ERVs are modeled "according to how it's designed to operate". The quotes are taken from a HERS trainer.

I designed my newly constructed home to be as energy efficient as reasonable. I hoped to get to a HERS score of 30 or lower. Though my HERS score has not yet been computed, I have been advised by the HERS rater that because of my choice of equipment the HERS score may not be as low as it might have been, had I used a less efficient Ground Source Heat Pump.

In Energy efficiency and durability | Asked By Ted Cummings | Jul 13 17
10 Answers

Heating a cold-climate off-grid superinsulated house

The house will be in New England, northern zone 5, high elevation, open to north winds. Good southern exposure but lots of windows for north view. Cathedral ceilings up to 18-20. Proposed insulation R40 walls, R65 roof, triple glazed European windows; very tight. (<1.0ACH50) There will be a PV system with battery back up and possibly solar thermal.

Do minisplits work for off grid situations? Solar thermal with radiant wall heaters? Anyone have experience with superinsulated off grid homes in this climate?

In Mechanicals | Asked By Bob Irving | Aug 11 13
4 Answers

How best to handle moisture inside concrete block basement walls?

I have read most of your basement moisture articles but don't see moisture in basement walls address directly. I have already re-graded around the house, fixed the gutters, installed an interior french drain, and run a dehumidifier. I keep the basement humidity very low due to mold concerns, no higher than 40%. When I drop the humidity probe into the walls it reads in the 70s.

In General questions | Asked By jwoerner | Jul 12 17
10 Answers

Confused and worried about minisplit sizing

We’re building a house in Toronto, two stories (both about 1500 sqft each), first floor R26, second floor R32, second floor ceiling R70, with HRV, de-humidifying system, window-to-wall ratio 12%, windows mostly face east and west, windows are Fibertec high-efficiency, fiberglass frame, low e-coating. Whole house will have hydronic floors for heating. We’re planning Mitsubishi mini-splits for A/C, but we’re very confused about sizing and placing of heads (and outdoor units).

In GBA Pro help | Asked By Thomas Kaempfen | Jul 9 17
8 Answers

Heat pump water heater for supplemental hydronic heating

I am in the process of designing a high performance home and am working on the HVAC system specs.

I am in mixed humid (zone 3 - Greenville, SC).

Duke Energy offers some reduced rates for Energy Star certified homes (I am waiting for Piedmont Natural Gas to get back with me on their rates). These rates are 5-6% below standard rates.

In Mechanicals | Asked By pnjfksx | Jul 12 17
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