Project Team

Other Team Members

Architect: Wagner Zaun Architecture, Duluth MN
Builder: Zeltwanger Construction, Hancock MN

Ratings, Awards and Recognition


The house was granted a HERS rating of 0.

HERS Index::

The clients, who hired us to design this home on their lake area property, had done their homework. They had a good grasp of what they wanted to acheive, and how they might get there. The goal from the onset was a net-zero home with as much passive solar advantage as they could acheive with a house that would not be ideally oriented. They wanted to be able to "age in place" with mobility friendly features like a curbless shower, and they wanted to make a minimal long-term environmental impact. With an understanding of mechanical system options, and a pre-selected builder who was already delving into high performance building techniques, they brought us on to help turn their ideas into reality. 

The Echo Lake Residence is a one-story, slab on grade, two bedroom, two bath home. The home combines 12" double stud exterior wall construction with better-than-average attic and sub-slab insulation, triple-glazed insulated fiberglass windows, a 7.7 KW PV array, and a ground source heat pump. The home was designed to blend well with the open, "prairie-ish" site and take advantage of the westerly lake views while adhering to the "not-so-big-house" principles. The house is simple in form and plan with a little extra architectural exuberance afforded to the entry porch and screened porch.

Quick Facts


Location Farwell, Minnesota
Building Type Single family detached residence
Project Type Zero Energy
Basis of Performance Claim Verified
Bedrooms 2
Bathrooms 2.0
Conditioned Floor Area 1,596 sq ft

Energy Summary

Energy Data Type Verified
Renewable Energy System Type(s) Photovoltaics, Geothermal

The house was granted a HERS rating of 0.

Annual renewable energy generated 10,450 kWh/year

Envelope and Mechanicals

Subslab assembly

The slab on grade main floor is a 4" concrete slab poured over 8" of XPS insulation (R-40)

Foundation wall assembly

The foundation is a 6" core ICF stem wall atop a continuous concrete strip footing.

Above grade wall assembly

All exterior above grade walls are 11-7/8" double stud walls with 2x4 inner and 2x6 outer studs aligned @ 16" on center. The cavities were filled with dense packed cellulose.

Door Assembly

Exterior doors are insulated fiberglass units. The patio door is a tilt-turn unit to match the window unit's performance and glazing specification. The entry door is an insulated fiberglass unit with dual pane 1/4 lite glass.

Air Changes per hour, ACH50 0.47 ACH50