The Pacifica Coastal Cottage was built in 1934 by the current occupant's father, a couple hundred yards from the Pacific shoreline, south of San Francisco. The original 700 ft2 shack was added onto haphazardly over the years to a total of 1,503 square feet, and it grew to 1,706 square feet in its 2008 DER. It has two bedrooms, two baths, and two occupants. It experiences approximately 3,200–3,700 HDD (Heating Degree Days) in Pacifica, California.
This house is notable for its daylighting strategies, which are especially valuable in a home that is occupied all day, every day. Significant efforts were made to create a well-insulated and airtight building, yet the owners expressed disappointment in the results of blower door diagnostic testing (about 6 ACH50), which had not previously been performed.
This is an exemplary project that preserved the historical character of a family heirloom while at the same time making huge advances in comfort, energy efficiency, and sustainability. (See the table below for more details.)
This home has consistently exported net energy during several months of the year ever since its completion in 2008.