Metal Architecture Home


Residence conserves energy

The owners of Casa Águila, a private residence in Ramona, Calif., set lofty sustainability goals for their house.The owners of Casa Águila, a private residence in Ramona, Calif., set lofty sustainability goals for their house. The project was designed for eventual grid-disconnection through utilization of battery power, photovoltaics and a 45-foot wind turbine with 17-foot blades. It is LEED Platinum certified and a Certified Passive House from the state. Additionally, the project has permits for on-site wastewater treatment and to collect rainwater for indoor use.

The metal roofing provided a high solar reflective index (SRI), 54, which reduces cooling energy loads during hot months. Because it was greater than 30, the SRI also contributed to LEED credits. The metal roof provides better water collection than some other materials, is noncombustible and recyclable. Cal Tech Roofing installed AEP Span's 24-gauge Design Span standing seam roof system in Dura Tech 5000 Cool Metallic Champagne.

For insulation, double-stud walls were filled with approximately 16-inch-thick GreenFiber cellulose supplied by US GreenFiber LLC. This created R-56 insulation. The roof framing bays were filled with 5 1/2-inch-thick GreenFiber cellulose. Above that, The Murus Co.'s 6 1/2-inch PUR polyurethane structural insulated panels (SIPs) were installed, providing R-60 insulation.

Protection from debris flying in high-winds was added to glazing in doors and windows because the house is located on a moutaintop in a high-wildfire area adjacent to Cleveland National Forest. The previous residence on the site was damaged by wildfire in 2007. Doors and windows were installed with tempered glass with a laminated outer layer to provide a measure of bullet proofing. The project utilized Unilux Inc.'s doors and windows with passive house, high-performance levels for U-value, solar heat gain coefficient and air infiltration.

Phase Change Energy Solutions Inc.'s BioPCM phase-change material was incorporated into the roof and both interior and exterior wall assemblies. The phase-change material provides a buffer against indoor temperature fluctuations. Additionally, Prosoco Inc.'s R-Guard air and vapor barrier was applied to the entire building envelope to provide air-sealing and meet a passive-house standard.

The project also included a photovoltaic array, solar thermal system and hydronic radiant floor system. For the photovoltaics, Precis Solar Inc. installed LG Electronics Inc.'s LG315N1C photovoltaic panels and DEGER Canada Inc.'s dual-axis solar tracking system.

A large solar thermal system provides heating for domestic hot water, space heating, and heating for a pool and spa. Adroit Energy Inc. installed SunEarth Inc.'s ThermoRay TRB-40 solar collectors for a solar thermal system.

Hydronic radiant floors provide space heating and cooling. Adroit Energy Inc. supplied and installed its hydronic radiant floor system. The heated floor systems are coupled with solar thermal energy and Daikin North America LLC's Altherma air-to-water heat pump. To respond to high temperatures during summertime, a ducted fan coil system that runs with cool water from the Daikin Altherma pump was installed.

Casa Águila, which translates as eagle house, was named for Golden Eagles that fly over the property. The 3,123-square-foot project was completed in January 2016.

Architect: Andrew Wilt Designs, Encinitas, Calif.,
General contractor: Alliance Green Builders, Encinitas,
Installer: Cal Tech Roofing, Solana Beach, Calif., (858) 481-4181
Photovoltaics installer: Precis Solar Inc., Wildomar, Calif.,
Doors/windows: Unilux Inc., Saddle Brook, N.J.,
Heat pump: Daikin North America LLC, Waller, Texas,
Hydronic radiant floor system/solar thermal system installer: Adroit Energy Inc., San Diego,
Insulation: US GreenFiber LLC, Charlotte, N.C.,
Metal roof panels: AEP Span, a division of ASC Profiles LLC, Fontana, Calif.,
Phase-change material: Phase Change Energy Solutions Inc., Asheboro, N.C.,
Photovoltaics: LG Electronics Inc., Englewood Cliffs, N.J.,
Solar collectors: SunEarth Inc., Fontana,
Solar tracking system: DEGER Canada Inc., Shelburne, Ontario, Canada,
Vapor barrier: Prosoco Inc., Lawrence, Kan.,