Central Coast Passive House Remodel

On an existing home built of concrete masonry unit (CMU) blocks, the homeowners looked to achieve a Passive House level of comfort and efficiency by aiming for EnerPHit certification, the Passive House certification standard for retrofits and remodels on existing homes and buildings.

To reach this goal, the existing home (which is also the location of the first use of hempcrete construction on a house in California) had the uninsulated CMU walls coated with Viscon, a vapor-permeable waterproofing and air-sealing membrane, and then wrapped by us with wood-fiber insulation boards made by Gutex and supplied at the time by 475 Building Supply.

The exterior finish over the wood-fiber insulation is a lime-plaster finish coating. The ventilation requirements of the home were met by installing a series of Heat Recovery Ventilation fans throughout the house, and a single 9,000 BTU, wall-mounted, mini-split heat pump met the sole source of heating and air-conditioning.  

This home is a near-perfect example of traditional California ranch-style architecture being brought to date and made comfortable, efficient, and durable for the next generation’s use and enjoyment while maintaining the classic exterior aesthetic and interior feel of that conventional architectural style.