Green Home, Healthy Home

The word “home” is synonomous with many things, both physical and emotional. Home is shelter. Home is family. When Allen Associates came across the Doering family, they knew how important it was for the two to come together, a beautiful, healthy place to house their entire family — and they did this with being very environmentally aware.

Transforming the Doering’s typical, older Santa Barbara tract home into an exemplary “green” remodel was the major challenge of this project. Built in the 1950s when neither energy efficiency nor indoor air quality was even considered, this house, like many others similar to it, had opportunities to be transformed into a comfortable and healthy home with a low operating budget. The construction budget was limited so cost-benefit issues drove the planning and decision making.
The solutions that the “green team” — client, architect Thompson Naylor Architects, and contractor Allen Associates — came up with improving energy efficiency, creating a healthy environment and staying within the alotted budget.

One of the goals of the project was to improve the energy efficiency and overall comfort of the entire house. In keeping with this strategy, the team decided on filling all walls with polyicynene insulation. It is a nonozone depleting, spray-in foam that fills every little void in a wall, resulting in an airtight building envelope. “Icynene is not used much in California because it costs a little more, but its performance is significantly better than other choices, and it is ideal for a retrofit project,” explains Karen Feeney, Green Resource manager for Allen Associates. The new exterior walls built using studs at 24 in. on center both to save on lumber (20 to 25 percent) and to accommodate more insulation.

The attic was insulated to R-30 with cellulose insulation — a recycled product that creates an excellent barrier to sound and temperature penetration. In an effort to further reduce heat gain in the building, radiant barriers were installed under the rafters. Radiant barriers deflect up to 25 percent of summer heat gain — an excellent investment that will add only a small increase in cost over using traditional roof sheeting. A new whole-house attic fan removes most of the remaining heat and keeps summer indoor air temperatures at a comfortable level. The fan has insulated doors that automatically close when the fan is not in use. All of the bedrooms will have ceiling fans as a final element on the menu of cooling strategies.

The final element in the conservation package is the glazing. New French doors and operable windows add natural light and promote circulation of fresh air. The windows are energy efficient, Low-E with a fiberglass exterior. Their fiberglass exterior — which expands and contracts with the glazing itself — makes the product very durable and will require minimal maintenance. The glazing configuration is different for each compass orientation so as to get good thermal gain in winter through the south facing units. In addition, radiant barrier paint with a vacuum microsphere additive was applied on the underside of the roof to reduce summer heat gain.

The above steps create a thermos like shell for the house — minimizing the need for space heating and completely eliminating the need for air conditioning. The minimal space heating that will be required is supplied by an on-demand water heater with two ports — one for domestic hot water and the other for space heating. The space heating port is linked to two fan coil heat exchangers, an inexpensive but effective heat delivery system. A passive solar water heater on the roof will serve as a preheater to the on-demand backup heater.