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Boulder Net-Zero Home


Single Family Residence


Boulder, Colorado

Year Completed


Design Team

Satto Rugg, Architect

General Contractor

Sightline Builders


Bodhgaia Architecture

xxx real estate

"What is that intangible energy one feels here...? A sense of joy and mindfulness infusing the space, arising from the care with which design and construction were undertaken? Can this intangible energy of beauty and harmony infuse all our works, large or small? How would we feel, what would our world look like, should this come to pass?
- Valerie Wedel, covering this residence for the 2015 Boulder Green Home Tour

This overgrown lot with an abandoned house contained a few beautiful trees including two 80’ silver maples. These two trees became the origin of the design. The house snakes around these two trees, forming an entry courtyard to the north and a private courtyard to the south. Each courtyard has its own guardian tree, providing shade and protection. The trees pin the house to the land, and the house rises up from its stone base to the 9:12 clay tile roof to speak to these majestic trees. 

The client, having grown up in Geneva, wanted to bring the style of French country homes into a modern expression in this house. He worked with the stucco and plaster contractor to not only direct color and texture, but also jumped in to apply a lot of the interior lime plaster himself. The German clay tile roof and custom zinc gutters are designed to last 100+ years.
The house was laid out to make the most of passive and active solar, with a long light-filled corridor facing south, reminiscent of the 18th century orangeries of Europe. The roof pitch is optimized for the 17Kw solar PV array. An internal greenhouse was inserted between the kitchen and the mediation wing.

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This residence scored a whopping negative 23 in the HERS rating system, making it Energy Star 5+ and a net energy producer. Some of the features that contribute to the advanced energy efficiency:

•    R-43 double-stud wall system @ ~12" thick
•    Extensive south-facing glazing for passive heat gain; built-in greenhouse segment

•    Alpen HP 750 series windows with U-value 0.18
•    Windows ‘tuned’ to orientation for SHGC and U-value
•    R-54 truss roof with 'energy heel'
•    Electric air source heat pump (runs off of PV system)
•    18 kW PV array (shown at right)
•    Heat recovery ventilator (UltimateAire, only 45 watts)
•    100-year roof
•    LED lighting throughhout


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