Designer and builder Andrew Michler recently built a passive home for himself near Fort Collins, Colorado, which is made from either naturally regenerative or recyclable materials, and by using the Cradle to Cradle methodology. Despite the fact that this home is located in a very cold region, he also wanted to find a substitute for the plastic foam insulation, which is typically used in these cases. Foam plastic insulation has high embodied energy, is made with hazardous chemicals and is full of toxic flame retardants.
He succeeded in this, and his solution is both ingenious and low cost. He did away with the slab altogether and replaced it with an old-fashioned ventilated crawl space, while filling the floor with insulation instead. This allowed him to wrap the whole house in a thick blanket of Roxul rock wool and cellulose insulation.
His home is a 1200 square foot off-grid house, which acts as the main residence, office and shop, while it was also designed to allow for easy reconfiguration. Once at the end of their life cycle, all the materials that it is made from will be easy to separate and recycle. Also, most of the materials the home is made of can be reabsorbed into its surrounding mountain environment once the home gets to the end of its lifespan.
The way he achieved this is by using mostly low-tech things, and traditional materials and building techniques. In other words, things developed before synthetic materials and HVAC systems became the standard, namely organic felt, mineral wool, and cellulose. According to Andrew, the future of sustainable design actually lies in looking to the past, and I can’t help but agree.
The walls of his home are basically deep trusses turned on end, which leaves enough space to fill with two feet of cellulose insulation. The only concession to modernity Andrew made was installing U-PVC windows, mostly for cost reasons.