Location: 630 Northstar Court, Boulder, Colorado
Price: $4,500,000
Original Year Built: 1976
Footprint: 3,654 square feet (5 bedrooms, 3 baths)
Lot Size: 0.21 acres
From the Listing: “Designed by Charles Haertling, one of Colorado’s most celebrated architects, this is not just a home—it’s a rare, livable work of art. Virtually no other Haertling home has undergone a renovation of this caliber, with a reverence for the original design that also maintains a livable, open, and functional floor plan supporting comfort, flow, and purpose. Originally built in 1976, this residence, shaped like twin cones, resembling a cassette tape in plan, is one of Haertling’s most iconic creations. Each tower is anchored by a sculptural, woodburning fireplace. Set against the backdrop of the foothills, the home offers remarkable Flatiron views, sitting like a sculpture in the landscape and blending geometry, nature, and light. Framed by walls of glass and grounded in organic materials, the home includes a meditation room, a tranquil water feature, a private hot tub, and over 1,600 square feet of decks and patios. Energy-efficient upgrades include a 4.5kW solar PV system, an EV charger, in-floor radiant heat, and two mini-splits for cooling and additional heating.”






