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About The home

The Sundial House

Emerging from the elevated rise of Alta Heights
Overlooking the many world class offerings in legendary & bustling Downtown Napa
Set on this rarely seen majestic 7.75 acre property
Offering an eco-inspired, artistically motivated, “eclipse formed” home with a passive solar design and aligned to the celestial guide of solstice
The views penetrate across the Napa Valley,  through the Carneros Region, over Mt Tamalpais and into the San Francisco bay
All the while embracing the harmony between the intrinsic & arid elements of Alta Heights and the environment that surrounds us all

Phyllis Hunt wanted something organic and welcoming. Working with Berkeley Architect, Craig Henritzy of Indigenous Designs, they created an observatory on a hill with elements of Native American Design. Additional vision came from some of Frank Lloyd Wright’s inspired homes using the organic principle's of allowing the site to influence a building design. These ideas were finished with features inspired by ancient ceremonial round homes that tribes had built in the region.


This 2,634 sq. ft., 3 bedrooms, 2 1/2 bathroom creation combines a “half circle” and “half ellipse” design. Each room has private and direct access to the outdoor patios and entertaining areas. The open kitchen arrangement offers a fireplace and the adjacent dining room overlooks the main living area. The southern exposure orientation, in combination with the window arrangement and concrete floors, creates the passive solar effect within the home. Your senses are heightened by the walls of windows and the intricate design of the home. The landscaped highlights the natural surroundings of Napa’s east side. All the while this home is just minutes to downtown Napa.

Having been referred to as the SunDial house, this unique property has been featured in Sunset Magazine’s “Building Tomorrow’s Home” and the book, “Living Homes", and featured on home and garden channel.


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Architecture & details


Developed in Europe, the primary building material consists of a recycled polystyrene and cement block called Rastra Block. Which is then rebarred and its cavity is filled with cement. This material, mixed with cement, and shaped into hollow forms, creates a portable, lightweight, and pliable building product. Rastra Block is a very portable and sculptable material and can be easily cut into rounded shapes with a hand tool.

Other qualities of Rastra Block:

  • Insulative Values offering an insulation rating of R38
  • The process applied is 7 times stronger than wood
  • Lightweight and portable
  • Easily shaped and sculpted into custom shapes and forms
  • Highly resistant to fire
  • Very tolerant against earthquakes

PROCESS: The Rostra Block was stacked vertically atop a stem wall. The plumbing and electrical lines were set into the hollow cavities of the block. Then the cavities were filled with cement. Rebar was placed into the wall system cavities before the concrete was formed making this house very tolerant of earthquakes.

The exterior was covered in a golden colored stucco. The interior walls were hand troweled with molted hewn plaster.


The sundial element of the house can be seen in the formal living room. A specially designed row of cement blocks have been placed in the center of the living room thus creating the living sundial. Daily, the room marks the solar noon on the row of laid cement blocks. Furthermore, the windows and custom shaped, interior and exterior, iron markings have been placed to track the summer & the winter solstice as well as the equinox by creating a shadow effect as the sun travels across the sky throughout the year. This marks the sun’s path through the windows, along the floor and onto the centerpiece lodgepole pine timbers and fireplace. The orientation of the house is designed to track the seasons.

  • Equinox window with interior and exterior markers
  • Winter Solstice window with interior and exterior markers
  • Summer Solstice window with directional markers

The home takes advantage of the alignment with the southern sky and the path of the sun through our hemisphere. The design offers elevated views through a large number of windows, varying in sizes, throughout the house. These many shaped and various sized windows, with strategic placement, along with the insulating qualities of the Rostra Block, combined with the cement floors creates a perfectly balanced passive solar system. Not to mention the access to views, the animals, and the light and stars. Thus creating what has been referred to as a solar observatory.



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This 7.75 acre property is set on a gentle rise along the palisades of Alta Heights. This rare parcel offers you the privacy and peacefulness that the home originally aspired to create. The many natural and native grasses, flowers, trees, and welcomed wildlife, work to balance the hustle and bustle of life with the peacefulness of the property.

The walking paths meander along and in and out of the rock outcroppings and trees. The many rock walls and patios offer multiple landings for observing one’s personal desire for privacy or another’s hope to watch the red tailed hawks display their aerobatic prowess along the backdrop of views across the valley.

The night sky is a wonder as well. Morning, afternoon or evening meals on one of the several observation pads offers  a unique perspective to the world below and above.

The rock walls and patios were all hand built with locally sourced stone.  As you explore this home and grounds, you are moved by the thoughtfulness and creative spirit it encompasses.

This is truly a unique Napa Valley Estate.



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Napa Valley, California

More than 400 wineries dot the fertile soils of Napa Valley, one of the world’s premier viticultural regions. But wine, as visitors quickly discover, is only the beginning. Stay in lavish resorts, charming bed & breakfasts or modern hotels. Find top-rated chefs at scores of restaurants who work alongside the farmers who tend this land. Take a hot air balloon ride or taste the bounty of the valley on a wine tour. Whatever your pleasure, the result is something understated and exceptional. 

Napa is the largest of Napa Valley’s five towns, and is conveniently located just an hour north of San Francisco and an hour south of Sacramento. This town offers an impressive diversity of food and activities. Check out the unexpected blend of urban activity – interactive street art, food trucks, and vibrant night life – combined with quaint Napa Valley character – a quiet river walk, hidden tasting rooms, and a lively farmers’ market.




"Your Alta Heights living experience offers you access to all the haunts of legendary downtown Napa..." 





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