Desert Rain House gets Living Building Challenge Certification
The Living Building Challenge is one tough building standard, probably the toughest in the world. There have not been a lot of buildings completed that have made it through, and Desert Rain is the first residential project to get certified. It has taken almost a decade since Thomas and Barbara Elliot decided to build an “extreme green dream home” and they have been living in it since 2013, but with the LBC you have to prove performance for a year:
The Living Building Challenge certification requires actual, rather than modeled or anticipated, performance across environmental, social and community impact. Therefore, projects must be operational for at least twelve consecutive months prior to evaluation.
Now it is done; from the LBC press release:
Six years in the making, Desert Rain earned certification by demonstrating that its five buildings produce more electricity than residents use each year and that 100% of water requirements are met by captured rainwater. In addition, toxic chemicals were screened from all building materials and all wood was reclaimed or Forest Stewardship Council certified. Human waste from the three residences is composted on site and all greywater is processed and reused for irrigation.
Place Petal© Desert Rain House The Living Building Challenge has seven “petals” that must be complied with, including a “place” petal. The new house is replacing two old ones that are described as being “near the end of their useful life.”
The original plan was to deconstruct one home and remodel the other, but the poor quality of construction and general condition of the homes made remodeling infeasible. Therefore, the team elected to carefully de-construct both homes and salvage materials for reuse.
As an architectural preservationist my first reaction was that tearing down two houses was not exactly appropriate. But when you look at the standard, under Limits to Growth, the LBC prohibits the use of greenfield sites. So it does make sense.
Water Petal© Desert Rain House When one looks at the Living Building Challenge, the Water Petal is perhaps the most challenging and the most troubling. It was tough to do;
Local average annual precipitation is only 12 inches and dry years can produce as little as 7 inches of moisture. In this demanding environment, achieving the Net Zero Water Imperative – supplying 100% of the project’s water needs from captured precipitation – is arguably the most challenging of the LBC Imperatives.
So they collect the water off all of the metal roofs with gravel filters on the downspouts, and
After passing through the gravel filters, harvested rainwater is conveyed via underground plumbing to a centrally located cistern beneath the main garage. The 30,000-gallon cistern was built into the foundation of the garage with its roof functioning as the floor for the garage. Harvested rainwater flows first into an entry chamber where any sedimentation can settle to the bottom. Water then passes through an Orenco Biotube filter (designed to remove 2/3 of any remaining suspended solids) before being stored in the main cistern chamber.
Collected rainwater passes through two additional filters before it is delivered to the house as potable water suitable for human consumption. First, microfiltration removes all remaining suspended solids and finally, an ultra violet (UV) disinfection unit ensures the water is sanitary and free of pathogens.
Bend Water/Screen capture
Meanwhile, the City of Bend Water department promises “a precious, high quality supply of cold, clear water. We are the envy of many other communities because our exceptional water comes from both surface and groundwater sources.”
I do believe that the Living Building Challenge is the world’s toughest, most rigorous and perhaps best building standard, but continue to question the logic of managing drinking water on site like this instead of relying on the larger community resource.
But it is all uphill from here; Desert Rain uses vacuum flush toilets and big Phoenix composting units with an evaporator system to handle all the black water. This is a great solution to the problem of wanting a conventional toilet experience with a conventional china bowl and no looking down at poop, but still being able to have a composting toilet.
They believe it to be “the first (non-institutional) vacuum plumbing system building approval in the U.S.”, but it likely isn't- Envirolet has been selling a vacuum toilet and composting system since 2005.
Energy Petal© Desert Rain House The house not only meets the net zero energy requirements, but has enough capacity to charge two electric cars. According to the LBC, "Single–family residences must demonstrate that sufficient back-up battery power is installed for emergency lighting (at least 10% of lighting load) and refrigeration use for up to one week for greater resiliency." However the Desert Rain page describes a 14.95 kW grid-tied array and makes no mention of batteries and backup.
There is also a solar thermal system providing hot water and space heating, and a solar hot air system to evaporate excess liquid from the composting unit. (Lots more technical detail on the Desert Rain page here)
Health Petal© Desert Rain House This is where the LBC really shines a light on a subject to a greater level of sophistication than any other certification, from its long red list of materials, to its testing of air quality, natural finishes, elimination of VOCs.
The American Clay plaster product used on the interior walls and ceilings of Desert Rain is completely free of VOCs and resists mold growth. The myrtlewood floors are finished with Osmo, a Swedish product made from plant-based oils and waxes. The wood ceilings and diamond-polished concrete floors are not finished with anything at all.
Materials Petal© Desert Rain House Over 500 materials got Trumpian extreme vetting, to minimize embodied carbon, reduce carbon footprint, shorten travel distances, use responsibly harvested and certified materials. Outside of LEDs made in China and irrigation valves made in Israel, pretty much everything was local.
Equity Petal© Desert Rain House Finally, there are the equity and beauty petals- both subjective. Equity in particular is tough:
The intent of the Equity Petal is to transform developments to foster a true, inclusive sense of community that is just and equitable regardless of an individual’s background, age, class, race, gender or sexual orientation. A society that embraces all sectors of humanity and allows the dignity of equal access and fair treatment is a civilization in the best position to make decisions that protect and restore the natural environment that sustains all of us.
The owners are maintaining an “open door” policy to educate others, and have not fenced the property. It is not a monster home that dominates the area but “The compound concept resulted in multiple smaller buildings clustered around courtyards to keep the scale more humane and to encourage a sense of community.”
Beauty Petal© Desert Rain House Beauty is, of course, in the eyes of the beholder. But they pull it off.
Desert Rain draws much of its beauty from the careful balance of natural materials, both on the interior and exterior. These materials impart a slightly rustic elegance, and also respect and reflect the landscape and regional culture and traditions.
The Living Building Challenge is really tough to do, but it does things that nobody else is even trying to do with petals like health and happiness, equity and beauty. I have worried about how well it scales, and I continue to question the logic of having electricity net-zero but connected to the grid, while water cannot be connected to the grid that supplies better water that is constantly tested.
But every building that meets the Living Building Challenge is a wonder, a monument to sustainable design, and a testament to the courage and endurance of the people who went through this process. Congratulations to all involved on this one. Read more at Desert Rain page and on the House website.