We've learned a lot throughout the design and construction of our LEED® project. Here's a brief breakdown of the considerations and features that contribute to green, sustainable building.
PLANNING & DESIGN
Compact, Efficient Design: One of the most important choices in resource and energy conservation.
Adaptability: The house is designed so an addition can be built on any of its four sides, and the mechanical space is sized for additional systems and upgrades.
Siting & Sun Tempering: Most of the window area faces south. In the winter, the sun will warm the living space during the day and shine on an insulated concrete slab at the walkout basement which will store some of the heat gained for gradual release. The roof overhang will shade the house from excessive solar heat gain in the summer, and west-facing glass is minimized to reduce cooling needs in the summer.
The house is sited at the edge between field and woods, with south and east windows facing the long view. Access to the outdoors is provided from all sides and living areas, so it is easy to stay in touch with the serene and natural surroundings on the property.
Second floor framing is heavy timber beams (from local New England forests) and decking which are exposed as the ceiling on the main floor, giving a warm feeling of the origins and strength of the structure.
A ceiling line which is open to the loft provides a sense of openness and airiness which is shared by both levels, with little wasted space or heated volume.
A wood burning stove with glass doors serves the traditional purpose of a hearth better and more efficiently than an open fireplace.
Durability: Here are just a few examples of the many ways durability, longevity, and ease of maintenance are built into the house from beginning to end:
Rain skin: Siding with an air space behind to promote drying of materials.
Galvalume metal roofing: This is for good looks as much as longevity, and is expected to last much longer than asphalt or wood roofing.
Roof overhangs: 2 foot overhangs on all sides keep much of the rain off siding, windows, and doors. This substantially increases the life span of these components, and helps the building to maintain "dry feet".
Aluminum clad window exteriors: No painting, no rot...
Entry roofs located over the three main doorways keep doors, floors and people drier in wet weather, and expand outdoor use possibilities.
Environmentally Sensitive Materials: Locally sourced materials include reclaimed Vermont ash floors milled in Woodbury, CT and a sealed concrete floor (no carpet, which requires intense use of manufacturing and often toxic chemicals); reclaimed tile and Fireslate counters; low water use bathroom fixtures; reclaimed materials for decking and patio; steel roof (steel is eminently reusable and recyclable); and low VOC paints and sheet wood products with no added VOC's.
Insulation: An advanced envelope design will achieve insulating values of close to R40 in the walls and R60 in the roof, and virtually eliminate "thermal bypasses", or conduits for heat to pass through building materials to the outside. Connecticut building code currently requires only R19 walls and R30 roof insulation.
Air infiltration will be substantially reduced by using rigid foam insulation outside the framing and a carefully installed air barrier.
Fresh Air: A heat exchange ventilation system provides continuous fresh air to the house while transferring heat from the bathroom exhaust air.
Photovoltaic Array: A grid tied 2 kilowatt array of photovoltaic panels on the roof will offset some of the electricity used by the house and feed electric power back to the power company when the house is not using it. The monthly and yearly electric bills will reflect the net of energy used and energy fed back to the power company. The potential of increasing this power array by 50% has been incorporated in the placement and design of the system.
Solar Hot Water: A two panel system with an auxiliary solar storage tank will heat much of the water used for domestic purposes. The high efficiency boiler which heats the house will supply an indirect fired water heater to augment the solar hot water supply as needed.
High Efficiency Appliances: Highly efficient space and water heating equipment, energy efficient household appliances and lighting. These go well beyond Energy Star's threshold standard to achieve a higher rating in the LEED for Homes system.