Could Affordable Eco-Housing Be in Your Backyard?

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Backyard BI(h)ome by UCLA Citylab and Kevin Daly Architects in Los Angeles, CA; Photo: Nico Marques / Photekt

Can LA solve its affordable housing crisis with demountable, plastic-skinned homes shared with lizards and other urban wildlife?

Students posing as “House Doctors” along with teachers and builders of the BIHOME; Photo: Shreya Malu of CityLAB

Can LA solve its affordable housing crisis with demountable, plastic-skinned homes shared with lizards and other urban wildlife?

That’s the modest goal of BIHOME, an energy-efficient and low-water consuming “lightweight cottage,” designed to be located in the backyards of homes in LA as a “habitat for people while also enhancing the backyard habitat for other species.”

The BIHOME (also written as Bi(h)OME, playing off of “biome” or ecosystem), is the creation of students in UCLA’s departments of architecture, urban design (known as cityLAB) and the Institute of the Environment and Sustainability, under the tutelage of architect Kevin Daly, cityLAB director Dana Cuff, and IOES professors Jon Christensen and Ursula Heise.

Last week they unveiled the results — in an unexpectedly pretty, 350-square feet demonstration house parked outside the Broad Art Center on UCLA’s campus.

Students sporting lab coats, teachers, staffers from Shrink Wrap Pros and UCLA’s facilities, structural engineer Ben Varela, and friends and families gathered for drinks in a pavilion-like structure made of pipe frame wrapped in shrink-wrapped plastic with a cardboard tube infill.

Backyard BIHOME by UCLA Citylab and Kevin Daly Architects in Los Angeles, CA; Photo: Nico Marques / Photekt

One visitor, Lila Higgins, Manager of “Citizen Science,” at the Natural History Museum of Los Angeles County, was very taken with the concept, which reflects the growing interest in the architecture community in biophilic design.

“Walking into the BIHOME,” she says, “I was excited to see plants and animals already inhabiting the prototype space. There were aphids on the milkweed plants, and argentine ants crawling through the soil. Even though the ants were an introduced species-not native here to Los Angeles, it is still life and I celebrated their existence. Living in a city, nature is sometimes hard to find, and that’s a real shame. With more plants and animals living in our city, we will actually make our city a better place to live—urban nature will help to make us happier and healthier human beings.”

The demo BIHOME is delightful, but raises all sorts of practical questions about its real-world application, among them just how open the intended occupants (extended family, renters) might be to sharing space with urban wildlife, and how open the city will be to this “lightweight cottage” landing in people’s backyards.

DnA got some answers from project leaders Dana Cuff, Kevin Daly, Jon Christensen, and Ursula Heise.

Rendering of the BIHOME, intended to be skinned in stream-lined EFTE, a thin, strong, translucent polymer. The demountable building, designed to cost no more than $100,000, would range in size from 250 square feet to 1200 square feet (the most allowable for a backyard home in Los Angeles). It would sit on a screw-jack foundation surrounded by a gabbion (low rock wall.) The gabbion and the wavy skin are envisioned as nesting spaces for urban wildlife.

DnA: What is the meaning of BIHOME and what is its goal?

Dana: The BIHOME is the culmination of several years of study by the design-research think tank, cityLAB-UCLA, into backyard homes. We want to find ways to improve housing in Los Angeles while at the same time enriching the environment. And it will surely help Mayor Garcetti reach his goal of 100,000 new units of housing.

DnA: Jon, you teach in the Institute of the Environment and Sustainability. What does this project have to do with climate change, drought and energy?

Jon: The BIHOME is a human-scale answer to the grand challenge of creating a sustainable LA. UCLA and the Institute have committed to a Grand Challenge with reach goals of making LA completely reliant on renewable energy and local water sources, while preserving biodiversity and our quality of life, by 2050. The Backyard BIHOME will be net-zero energy, that is, it will produce as much energy as it consumes, and possibly more than it consumes. It will be low water use, with a composting toilet and a gray water system for irrigating the surrounding landscape. And it will enhance backyard habitat for biodiversity.

DnA: How does the house enable coexistence with other species and why is that important?

Ursula: Many urban planners, architects and theorists over the last couple of decades have started to re-envision large cities not as biodiversity wastelands, but as multispecies habitats (Jennifer Wolch‘s idea of the “zoöpolis” is an example). Any time we put up a building, we take up space that is also used as habitat by other species – plants as well as animals and microorganisms. This is particularly true when a building takes up space that was formerly part of a backyard – and quite a few people expressed concern over the loss of green space in the preliminary surveys that CityLab has conducted over the last few years. So the goal of the BIHOME is to recreate and enhance habitat that would be lost with other kinds of construction through the way in which the gabion foundation and some of the walls will be designed to offer space for plants and animals to live: the gabion offers habitat to lizards, the walls will be configured variously to offer space for plants, bird nest boxes, bat houses, or insect hotels.

A screen inside the Backyard BIHOME provides nesting places for bats and butterflies; photo: Nico Marques / Photekt
A screen inside the Backyard BIHOME provides nesting places for bats and butterflies; photo: Nico Marques / Photekt

DnA: But houses are generally designed to keep other species at bay, with the exception of pets. Have you found people are receptive to this concept or put off at the idea of sharing space with lizards and ants?

Ursula: Right, different people have very different attitudes toward particular plants and animals! But certainly, there are some patterns – people tend to like lizards better than snakes, butterflies better than mosquitoes, songbirds better than bats. Some of these biases are justified (you have to be careful about attracting mosquitoes to houses), others are not and call for a change in the kinds of stories we tell about our relationships with other species. Many of these stories are rich in misconceptions and inaccurate information: our relationship to bats, for example, is pretty seriously deformed by vampire stories and Halloween imagery! Even so, clearly the BIHOME aims to balance features that are hardwired into the structure with features that people can choose: not everyone needs to have bee hotels built in.

DnA: You’ve designed the building to be super lightweight, made of EFTE, but are these plastics-based materials conducive to creating habitat for other species? 

Kevin: There are many ways that architecture can create habitats, and different materials have different advantages. We shouldn’t forget that it isn’t just building materials but also the surrounding landscape that make homes livable for various species.

Ursula: One advantage EFTE and plastics more generally have is that they’re extremely moldable into different shapes that can be made to adjust to the surfaces and cavities that different species prefer. So long as a structure offers the right kind of shape and texture, animals and plants can be quite adaptable – birds use metal tubes and rubber tires for nests, old oil platforms turn into coral reefs. And many nest boxes these days are made from different kinds of plastics.

DnA: The house is designed to be demountable. What happens to the birds nests/butterflies etc if the house is uprooted?

Ursula: Well, the basic idea is that at that moment you regain green space in your backyard, so the plants and nest boxes could be pretty easily moved to the garden around it. The gabion is the one exception – that’d take a greater effort in that rock piles would need to be created for lizards instead. It’s good to remember in all of this that many species naturally move around anyway within a territory – butterflies won’t mind if their host plants grow in a somewhat different patch from year to year.

Backyard BIHOME by UCLA Citylab and Kevin Daly Architects in Los Angeles, CA; Photo: Nico Marques / Photekt
Backyard BIHOME by UCLA Citylab and Kevin Daly Architects in Los Angeles, CA; Photo: Nico Marques / Photekt

DnA: The students wore lab coats for the unveiling. What was the message intended by this uniform? Health? Data? A scientific approach to dwellings?

Jon: All of the above! Health — the Backyard BIHOME is a beautiful and healthy dwelling for people and other species. Data — we’re fact-based and the design is driven by making a difference in energy, water, and biodiversity. Science — we’ll be studying the BIHOMEs, as they get built, on all of these dimensions to see how they do and improve. And the BI(h)OME itself is the produce of a lab — cityLAB — that brought together faculty, students, and staff from across campus to produce this experimental design.

DnA: How did the Institute For the Environment become allied with the architecture and planning students? And what were the challenges/rewards? Did students in both departments gain new insights into their disciplines?

Jon: The Backyard BIHOME is one part of some very exciting moves that are happening to bring the humanities and sciences and design disciplines together at UCLA to address real world problems, particularly around the environment and cities. Really interesting things happen when you bring together the critical disciplines of the humanities, where students and scholars often work alone on projects, with the generative design disciplines, where students and faculty and practitioners often work together in studios and build things, and then add in the experimental scientists, who often work in lab groups. It’s sometimes challenging to go back and forth between being critical (and seeing all the ways something might not work) and being generative (making it work!) and being scientific (conducting experiments to see how it does or does not work). But the rewards are enormous, in terms of what we learn from each other, but also in enriching the work we do in the world.

DnA: Visitors to the model bihome generally found it very attractive and decorative. Would that be the goal of the real thing?

Jon: For sure. Beauty is so important. If we don’t include beauty in our program for conservation and environmental sustainability, we won’t succeed.

Ursula: Yes. Many people immediately experience the uplift that comes from living and working in a beautiful environment. We already spend lots of time in ugly or poorly designed or badly maintained buildings – it’s great if the BIHOME can offer an alternative to that.

Dana: A real strength of this version and the next “real” one, wherever that might be built, is that they spark the imagination. People haven’t seen anything quite like the BIHOME before, so they are intrigued to learn more about it. It’s important that we demonstrate that living in smaller spaces, with innovative architecture, using fewer resources can be comfortable and hip at the same time.

Bihome being built
BIHOME under construction

DnA: How similar or different is the Bihome concept to prefab?

Dana: There have been many attempts in recent architectural history to build with modules, prefab components, or factory-assembly. Everyone is searching for both simpler means of construction and greater economies. But most of the prefab solutions have either been quite basic (like the Katrina trailers) and barely suitable for emergency housing, or not at all affordable (like some of the local systems tested around LA). The BIHOME isn’t prefab or components; it is a lightweight building system that is made of super-affordable materials, that can be easily assembled and customized for different backyards.

DnA: What about the practicalities of getting this built in reality (zoning and other constraints)?

Dana: Since 2009, single family homes in the City of Los Angeles are allowed to add a second unit, so the zoning already permits “granny flats” like the BIHOME. Of the 500,000 single family homes there, about 20% (or 100,000) rather easily meet the further requirements for setbacks, square footage, and so on. Another 15% of the lots would be easy with a few tweaks to the current building regulations, and these are being addressed by “re:code LA.” The main constraint that restricts a lot of the remaining lots is the parking requirement. As LA heads into a wide public conversation about transit, congestion, and our auto-dominated landscape, the residential parking requirements should be reconsidered too.

DnA: What happens next? Will the demo home be displayed anywhere? And will this lead to further iterations?

Dana: At cityLAB-UCLA, we’re especially interested in building one or more fully functioning BIHOMEs where they could stay in place, be inhabited for a few years, and could be studied in terms of environmental performance. I could imagine this happening where housing is in critically short supply, so we could meet a very human need.

Jon: We’re hoping to install a fully functioning Backyard BIHOME at next summer’s Urban Nature Festival at the Natural History Museum of Los Angeles County to share how this can really get done — you could have one in your backyard!

Backyard BIHOME at night, by UCLA Citylab and Kevin Daly Architects in Los Angeles, CA. Photo by Nico Marques / Photekt
Backyard BIHOME at night, by UCLA Citylab and Kevin Daly Architects in Los Angeles, CA. Photo by Nico Marques / Photekt