The project to renovate a home to create an improved indoor environment included, in addition to energy, lighting, and aesthetic issues, a focus on improving the indoor air quality above current standards by careful selection of materials introduced into the structure. The effort required vigilance and persistence, as material choices traditionally have been driven solely by aesthetics, durability and ease of installation (and we did not want to give up those qualities).
Over time the industry has discovered health issues or questions with many accepted materials (lead in paint, formaldehyde in composite materials), and many of todays standard construction materials contain extremely complicated chemical formulations, specialized glues, etc. including many volatile organic compounds and petroleum derivatives (which are a noticeable issue for the chemically sensitive persons). To remove as much of this mystery as possible from the components, we selected materials with more natural compositions or formulations specifically designed to reduce levels of items such as airbone compounds. Though in a few specialty areas, the options are still limited, in general we were able to find options with healthier components that can be used with standard construction techniques.
The house in particular suffered from the typical thermal and visual issues with aluminum single pane windows, inexpensive hollow-core doors and other components, lack of ventilation in wet areas such as bathrooms, poor daylighting, and years of overpainting and wear and tear and dated color choices on the carpet and walls.
Interestingly, in this 1959 California tract home construction, many of todays complicated chemical formulations for construction were unavailable. For example, the frame - walls, joists, etc - is simple 2x4 and 2x6 Douglas Fir construction, including a 2x6 solid Douglas Fir subfloor, with no glue-laminates or engineered woods. (And there was no insulation in the walls!)
Potential toxins did exist in the 15 year old carpet and cushioning, paints and wallpapers dating back to 1959, and mold around the bathrooms due to their poor ventilation. The attic was full off several feet of blown-in fiberglass insulation which, while creating a good thermal barrier, created an environment where pests could not be easily seen, and any workers in the attic were subject to dealing with the fibers. Subtle access points to the attic from pests were also to be eliminated.
Other design issues not related to chemical risks were the small size of the house and desire to avoid changing the structure for cost reasons, and to adhere to a general philosophy of maximizing utility of existing construction and avoiding use of natural resources to construct rarely-used rooms covering more of the landscape.
Maximizing closet space, creating more intimacy with the backyard/pool area from in the master bedroom, and fitting dual sinks into the small master bath were adressed. Flexibility was left for an eventual re-pipe of the house along with changes to the master shower (which will result in more natural light in the vanity area). The re-pipe is left until the kitchen/laundry/master shower remodel designs are executed. Those projects will extend the philosophy of maximizing space utility and flexibility, daylighting, and healthier construction methods.