Ever since I cut school to attend the first Earth Day I'd been day dreaming about building a "Green Home". I papered my walls with sketches of tree houses, beach houses and loft conversions. But within the first cottage I managed to build, the clients were only able to afford a few energy saving features: a passive solar orientation, an evergreen wind break and a thermal chimney. As the eighties progressed and my clients became more substantial, I had the opportunity to build a home that incorporated many of the best practices of that time. Now from the depths of the next great recession, I've taken the time to look back and assess how the structure and technology held up. Was the investment wise? Or did they squander their capital on gimmicks? What did we mean by "green" way back then anyway?
Pretty much the same thing as now, natural materials and sustainable products that were harvested from renewable resources. Energy efficiency-making good use of new technology combined with a common sense approach to taking advantage of the natural environment the good Lord provided us.
The clients had discovered the perfect building site. Located at the end of a private lane, the densely wooded upland with a south facing slope provided us the opportunity to carve the structure into the hillside. The temperature underground remains relatively constant at approximately 56 degrees Fahrenheit-allowing the lower level to remain protected in the icy winter and cool in the sweltering summer. Here in the Delaware Valley, heating is the greatest energy expense. So by building into the hillside and orienting the majority of the glazing toward the south, we were able to maximize the warming affect of the sun, while limiting the northern walls exposure.
We surgically cleared the majestic oaks, elms and cedars, replanting evergreen trees to the northwest to reinforce the wind break. Limiting the planting of lawn area we opted instead to enhance the woods: with ferns, wildflowers, rhododendron and grasses. Then we added a walled knot garden where select herbs and vegetables would be protected from the deer.
The building form itself was a traditional gabled structure conceived purposefully as a series of cubes; the cube being one of the most efficient forms to construct and condition. A 1600 square foot foundation as a 40 foot x 40 foot square has 160 lineal feet of wall but a 20 foot x 80 foot rectangle has 200 lineal feet.
The exterior materials: Pennsylvania fieldstone, western red cedar shakes & siding, lime, sand & cement stucco while echoing the indigenous German barns in the region, were light in color to reflect the sun, reducing the need for air conditioning. The deep overhangs reduced the amount of mid-summer summer sun entering the building but during the winter when the sun's arc was lower, allowed full daytime heating of the natural terracotta and tile floors. A concrete sub floor on the ground level and wet bed cement base on the main level created a thermal mass that helped store the sun's heat for release later.
As I recount the structural systems I amazed that very little has really changed in 18 years. We employed: open web floor trusses, locally milled heavy timber ceiling trusses, oriented strand board sheathing, thermopane windows, insulated doors, Tyvek building wrap, soffit & ridge vent and 2" x 6" walls stuffed with R-19 batt insulation; all still currently endorsed best practices.The mechanical systems were a different story. The clients chose to be pioneers-installing cutting edge ground loop geothermal heat pumps. Looking back I compare the three zone system with seven individual circulating pumps and countless valves to the Model-T Ford; an ad hoc assembly of individual machines never meant to be combined, that sputtered and shuttered for years until the replacement parts became unavailable and the clients finally gave up. They replaced it with a dual fuel hybrid. An electric heat pump and a variable speed 93-98 % efficient propane boiler that has proven both reliable and economical. Lesson learned; being the first is risky!
But the other included technology, ceiling fans with winter operating modes, set back programmable thermostats, thermostatically controlled attic exhaust fans, Heatilator wood burning fireplaces with outside air intakes and recirculating fans, an air lock rear entry and R-60 cellulose ceiling insulation are all still relevant today. And although I have a difficult time recommending it, I'm told geothermal systems have progressed as well.
They added Polaroid window tinting film when it became available and installed custom wood louvers in western facing windows to reduce unwanted heat gain while maintaining ventilation. They purchased CFL's in the frequently used lighting fixtures and upgraded to solar powered attic fans.
So what next? We purposefully set the south facing roof pitch to 45 degrees in the hope of installing solar someday. PA and Federal programs are now available for financial assistance making both photovoltaic and hot water generating solar panels more affordable. Their wish list also includes solar window shade technology that has come to the market, wherein a computer monitors the sun's axis deploying window screens automatically to reduce solar heating. And a heat recovery ventilator to bring in fresh air exchanging it with the air being expelled, transferring the energy and filtering contaminants at the same time.
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