A simple passive solar detail

Ever since I came to live in Park City, I’ve placed enormous importance on choosing a home site with true southern exposure. 

After spending a quarter century in a shaded location, back in the Alps, where my parents’ home received only a few hours of winter sun, I learned firsthand how profoundly mountain sunlight affects both comfort and morale. Of course, site orientation is only half the equation — architecture must do the rest. 

At 7,000 feet, our sun is stronger, our winters are colder, and our skies are clearer, which makes solar geometry one of the most powerful and overlooked design tools. I’ve always been surprised by how little attention many local architects give to passive‑solar principles. 

When we built our home in 2013, I insisted on deep south‑facing eaves — in our case, 7 feet — to block the high summer sun while welcoming the low winter sun. At this latitude, the sun’s altitude swings nearly 47° between seasons, so a well‑designed overhang can dramatically reduce summer heat gain while providing free warmth in winter. 

The photo below was taken on July 7, shortly after the summer solstice at 11 a.m. MDST, and it shows exactly how the eaves perform: full shade in summer, full sun in winter.

Passive solar isn’t complicated — it’s simply good mountain architecture.