Linda Yates and Paul Holland had decided long ago that they wanted to build a home that would meet very stringent conservationist expectations. More precisely, they wanted to construct a home that would fit into its ecosystem perfectly while restoring the land around it to a state that existed before widespread human settlement began. The construction of the Tah.Mah.Lah. House (which means “mountain lion” in Native American Ohlone) was finished in 2011 and has since earned the LEED Platinum for Homes certification.

The 5,600-square-foot house was designed by HKS Hill Glazier Studio and is located in Portola Valley, California. Despite its size, the home is passive and also restorative, meaning that it has a positive impact on the environment. A number of experts from various fields of study, such as engineers, energy specialists, wildlife biologists and even artists, were consulted while drawing up the plans for the house. The main aim of the designers and owners was to build a house that would generate more energy than it uses, while also rebuilding habitat, saving and repurposing water, and reducing and reusing waste.

The Tah.Mah.Lah house uses city water for taps. However, the graywater from showers and the blackwater from toilets is treated in a septic system, then goes through subsurface irrigation to water the yard’s meadow of native grasses. There is also a 50,000-gallon underground cistern for collecting rainwater that is then used to water the plants. Most of the materials used to build the home were salvaged. The recycled steel roof, reused limestone fireplaces, kitchen hood and hand railings were repurposed from a nearby 102-year-old granary.

The structure of the house is made of FSC certified cedar, while the wooden floors were salvaged from old barns. Also no paint, ducts, or fossil fuels were used in the construction process. The house is heated by a geothermal system that pumps water deep underground to be warmed by the Earth’s thermal energy, then pushes it back up to heat the floorboards of the house. Additional energy is also supplied via a roof top mounted 7KW, 120-panel solar array.




To strictly monitor the energy consumption the home was also fitted with a Control4 monitoring system. This system controls the LED lighting, the motorized MechoShades, as well as the heat recovery ventilators (HRVs). It is also equipped with occupancy sensors throughout the home, which turn lights off after 10 minutes of room vacancy. The system can also be set to perform all these energy saving tasks automatically.