Our growing children, a boy and a girl, were sharing a bedroom in our small, 2 bedroom 1 bath house, so we knew we had to move or remodel. We liked our neighborhood so we decided to remodel, expanding to 4 bedrooms and 2 baths. Our goal was to create a beautiful and healthy integral green home combining a tight building envelope, high insulation values, daylighting and natural light, active and passive ventilation, low energy use, solar hot water and solar electrical production, and sustainable and non-toxic finishes.
75% of the original structure was removed, salvaging most of the old 2x framing material. A new foundation was poured using 30% flyash. Advanced framing techniques were used along with FSC certified lumber and engineered ‘I’ joists. The exterior walls were framed with 2x6’s at 24” on center to allow for thicker insulation and better sound control. For a tight building envelope, all penetrations through the exterior envelope and all exterior doors and windows were caulked, or sealed with spray foam. All the walls and underfloor areas were insulated with cotton batts while all the ceilings were insulated to R-42 with blown-in cellulose. We exceeded the Title 24 Energy code by 65%.
Energy-efficient Marvin windows, supplied by V&W Patio Door and Window Co. (www.vandwpatiodoor.com). were used. High windows were placed on the south side of the house to allow for maximum insolation and passive heating in the winter while in the summer, the high angle of the sun allows very little direct sunlight to penetrate the living space, keeping the house cooler. An active ventilation strategy consists of a 90% efficient energy recovery ventilator providing continuous fresh air. A passive ventilation strategy with high operable windows in the tallest part of the stairwell creates a ‘stack effect,’ drawing warm air up and out of the house in the summer to provide natural cooling. For energy efficiency, Energy Star appliances were installed in the kitchen. A 95% efficient forced-air furnace was installed. A solar hot water heating system was supplied by Heliodyne, Inc. (www.heliodyne.com) with by two 4’x8’ panels providing 75-80% of the hot water needs for our family of four. 100% of the electrical use of the house is offset by the installation of a 2.1 kW photovoltaic array installed.
A variety of sustainable and low-toxicity finishes were used. Bamboo flooring was installed by Amber Flooring Co. (www.amberflooring.com) and bamboo ply was used for all the new cabinetry along with formaldehyde-free plywood boxes. FSC certified trim was used on the interior as well as exterior. The exterior was partly done in fire- and rot-resistant cement board siding. Low and non-voc paints and sealers were used. A recycled-content Icestone counter top was installed in the master bath. The landscaping was done with an efficient drip irrigation system and drought tolerant plants.
In summary, an integrated approach to green building was used to create an energy-efficient, comfortable, and beautiful modern home. The use of natural light creates a delightful sense of openness and well-being and a strong connection to the outdoors through the changing light of the seasons.
