Net Zero Restoration of 1936 Artist Built Cottage in Palo Alto
When Marc Porat bought the craftsman home built by the 20’s artist and architect Pedro de Lemos in 1936, he completely upgraded the home to PassiveHaus Net Zero energy standards, to demonstrate just what is possible, even with energy-inefficient housing stock.
MarcÂ is the co-founder of the only US company already building windows to PassivHaus standards of insulation. His company, Serious Materials began by innovating much more energy efficient and eco-friendly sheet rock, and has expanded to include “serious window insulation” with R values up to 13, which is almost like aÂ wall: about R25. Most US windows are only R2 or so.
A Net Zero house has to be completely sealed to be energy efficient. Then fresh air is brought into the tightly sealed house and conditioned first and sent through a complete house air filtration system with hospital-grade filters and hydronic air handlers keep the indoor air fresh and free of pollutants that build up in homes. A heat pump conditions the air so that less energy is used heating or cooling.
The rooms are peaceful and super quiet thanks to Serious Materials QuietRock soundproof drywall.The exterior walls were insulated with cellulose insulation made from shredded newspapers and coated with borate as a fire retardant which prevents any air infiltration.
Once the energy waste was eliminated, he put a 4 KW solar system on the roof to supply electricity on site: a much smaller system than would have been needed to supply the home’s energy use before the retrofit. To make the house as energy efficient as possible, he first had efficiency analysts at Recurve examine the energy use and model it with energy analysis software, revealing energy leaks in the floors, windows, walls, attic and ducts.
Marc kept and insulated around the original antique windows, but created a detachable storm window high R-value fiberglass storm windows to slip on inside in Winter, that completely seals the window. These simply attach and detach magnetically on the inside.
If you live nearby, it is open for tours and your questions once a month.
Source:Â Palo Alto Net Zero House