High performance in a quiet modern aesthetic
This is just one of a series of high-performing homes highlighted in the spring 2017 issue of GHM Homes. See the rest here.
Photo: Trent Bell
Freeport, Maine
A CUSTOMIZED VERSION of GO Logic’s 1600 sf predesigned high performance home model, this 3-bedroom house features exceptionally low energy costs, amounting to $600 a year in electricity and just $200 additional for biobricks for the wood stove. It features an open interior with exposed concrete flooring throughout, an important element of the home’s energy performance that helps to regulate interior temperatures.
Making use of passive solar gain and a highly-insulated shell, the home was built to the German Passive House Standard, which offers a 90% improvement to space heating when compared to a code compliant home. It has a near zero approach to energy usage, meaning that the energy produced by the 4.6 kwh solar panels nearly covers the total energy needs for the house.
“The house is draft free and comfortable all the time,” said the owner, commenting further that as of Dec. 21, they had yet to turn on the heat and the temperature in the house had not dipped below 65 degrees.
Why we like it: While not technically a Passive House, this home was designed to meet the passive house standards. This home delivers high performance in a quiet modern aesthetic. As expected with a Passive House, the building envelope features high levels of insulation, but its more unique construction method can be found at its foundation: a raft slab of concrete and granular fill that rests on a sub-slab of 8” of expanded polystyrene insulation that turns up 90 degrees at the foundation edge to maintain a continuous exterior layer of insulation around the entire home.
EFFICIENCY:
Near Passive House standards. Heating energy demand – 4.5 kBtu/ sq ft per year. $600 annual cost for electricity and $200 for biobricks for the wood stove.
BUILDING ENVELOPE:
Slab—4” concrete over 8” of rigid EPS insulation R-40. Walls—2 x 6 with 8” SIP using EPS foam R-50. Roof—Truss system with 24” of loose fill cellulose R-78. Windows—Triple pane German tilt-turn. Airtightness—ACH50 – 0.5
SYSTEMS:
Heating and Cooling—Electric baseboard + wood stove. Ventilation—Zehnder ERV.
RENEWABLES:
4.6 KW Photovoltaic array.
SIZE:
1680 sq ft, not including open deck and garage
COST:
$250/sq ft including site, garage, deck, solar
PROJECT TEAM
DESIGNER: GO Logic
BUILDER: GO Logic
RENEWABLES: ReVision Energy
ENERGY/PERFORMANCE CONSULTANT: GO Logic
This article was reprinted from the spring 2017 issue of Green & Healthy Maine Homes. Subscribe today!