The Beeler house at the time of purchase in 1998.
In 1997, George and Ellen Beeler “decided to get serious about living a green lifestyle.” This included living in town to reduce automobile fuel use and improving an existing house. George is an architect with a long-standing commitment to ecological design, so this remodel became a living laboratory.
The house they chose was built in 1940. It had single-pane aluminum windows, the original gas furnace, and no insulation or roof overhangs. There were no available data on the prior owner’s energy use.
Phase I (1998):
Upgraded the building envelope:
- added R-30 blown-in cellulose attic insulation;
- added R-13 dense-pack cellulose wall insulation between the 2 x 4 studs at the main living level;
- added R-20 dense-pack cellulose wall insulation between the 2 x 6 studs at the ground floor;
- added R-7 EPS insulation board to the outside of the concrete basement walls;
- closed off basement louvers that had been vented to the outside; and
- replaced the existing single-glazed aluminum windows with low-e2 glass in fiberglass frames with argon fill. (Replacing the single-glazed arched window in the living room would have been too expensive, so they kept it and added an R-4 triple-honeycomb shade.)
Improved the comfort systems:
- replaced the existing 60% efficient furnace with a 96% efficient sealed-combustion condensing natural-gas furnace with a high-efficiency air filter, and a very efficient variable-speed blower, allowing use of manual dampers to shut off heat to unused rooms;
- added a multisetback thermostat;
- replaced the conventional water heater with a tankless model;
- chose the most efficient ENERGY STAR appliances (when the PV system was installed in Phase II, having paid $100 more for the refrigerator saved $1,000 in PV panels);
- changed almost all the incandescent lights to fluorescents or CFLs; and
- added a whole-house fan for night cooling.
Reduced water use:
- installed water-efficient fixtures and appliances;
- installed a Taco on-demand hot-water circulation pump;
- installed high-efficiency drip irrigation (using nonpotable shallow-well water); and
- installed a 1.5-gallons-per-flush toilet.
Phase I results
Energy use for space and water heating was reduced by 70%, and electricity use was reduced by 80%.
Phase II (2005):
Added renewable-energy systems:
- installed a 2.5kW PV system;
- installed Solar Wall solar air heating;
- added a roof overhang over south-facing windows for summer shading;
- captured passive-solar heat gain by opening window coverings during the day and closing them at night; and
- installed a wind-driven turbine ventilator for natural ventilation and whole-house night cooling.
Further reduced water use:
- installed steel roofing to harvest rainwater in the future;
- captured storm water to recharge the groundwater; and
- installed a graywater system for irrigation.
South side of the house after Phase II: new PV system, solar air heater, and wind-driven turbine ventilator.
Phase II results
Summer comfort was greatly improved. In the first year, the PV system brought electricity consumption from the utility down to zero and produced over 1,465 kWh, reducing the household CO2 production by 4,301 lb. Solar air heating reduced annual natural-gas use from 309 therms in 2001 to 167 therms in 2006. (However, higher thermostat settings to accommodate Ellen’s fibromyalgia brought natural-gas use up to 185 therms by 2009.)
Phase III (2011–12):
Aiming to meet the 1000 Home Challenge, the Beelers improved the energy efficiency of their house before adding more renewable energy to achieve net zero energy:
- turned the den into a cocoon for Ellen, whose fibromyalgia requires warmth;
- added a solar air-heating duct to the den cocoon;
- improved air sealing to reduce air infiltration;
- increased attic insulation from R-30 to R-50;
- insulated the hot-water pipes;
- reinforced the house structure against earthquake and severe wind;
- improved water efficiency by replacing the toilet with a 0.8-gallon-per-flush Niagara Stealth model;
- installed new kitchen and bath faucets with separate hot- and cold-water valves (to minimize hot-water use); and
- installed more-efficient exhaust fans in the kitchen range hood and the bathroom.
Top: Southeast corner of the house after Phase III. Bottom: Direct-gain solar heating keeps the living room warm on sunny days.
Phase III results
Blower door tests before and after air sealing showed a 35% reduction in infiltration. Natural-gas use for space heating and water heating was reduced from 185 to 154 therms per year. Water use dropped to 48 gallons per day, a 43% reduction since 2003 (before which there had been dramatic water use reduction, but those data aren’t available).
The arched living room window remained single pane due to the high cost of a custom arched window; a three-layer R-4 honeycomb interior shade keeps some heat from escaping. The cable trellis was modified to shade the lower office door, but not the living room window.
George says they would have done a few things differently if they’d known in 1998 what they know now:
- prepare a phased rehabilitation master plan (the phasing shown above wasn’t planned);
- improve the building envelope enough in Phase I to eliminate the need for a conventional heating system;
- invest in a very-high-efficiency water heater for space heating and domestic hot water;
- perform quality assurance testing as work progressed;
- obtain additional financing to add a sloped roof in Phase I, to make possible major air sealing in the attic and an increase in roof insulation to R-50;
- replace the stucco siding, to make possible major air sealing in the walls and the installation of 2-inch rigid insulation board to raise total wall R-value to 26; and
- reduce the size of west- and north-facing windows since the existing windows are much larger than they need.
Photo Credit: George Beeler, AIM Associates