The fire-resistant structure is clad in corrugated Cor-Ten steel that has been left to rust for easy maintenance. Instead of fussy landscaping, the family spread seed for native grasses and wildflowers that they let fill in naturally.  Photo 4 of 7 in A Sustainable Retreat Rises From a Fire-Devastated Site in Boulder

A Sustainable Retreat Rises From a Fire-Devastated Site in Boulder

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The fire-resistant structure is clad in corrugated Cor-Ten steel that has been left to rust for easy maintenance. Instead of fussy landscaping, the family spread seed for native grasses and wildflowers that they let fill in naturally.