Up On the Roof

Up On the Roof

NorthBay biz takes a look at a growing architecture trend thats taking root here in the North Bayliving walls and roofs.

Theres an old saying pack rats often employ to justify their obsession with saving everything: If you wait long enough, it will come back in style.

The same could be said for one of the latest trends in green architectureliving roofs. While many promote them as a modern day antidote to reducing our carbon footprint, the fact of the matter is theyve been around for thousands of years. A primary example is the Hanging Gardens of Babylon. which was one of the original ancient wonders of the world.

Put simply, a living roof or wall is one thats covered with soil or another growing medium that allows for vegetation. There are two basic types: intensive, which are thicker, support more vegetation and are heavier and require more maintenance; and extensive, which have shallow growing mediums, smaller plantings and are much lighter.

One of the most famous green roofs in the Bay Area sits atop the newly redesigned California Academy of Sciences in Golden Gate Park. Others that might not immediately come to mind include Union Square (built over a parking garage) and Yerba Buena Gardens (which covers the original Moscone Center ) in San Francisco and Gallo of Sonoma s soccer field off Dry Creek Road in Healdsburg (which serves as the roof of the mega-winerys underground barrel cellar).

Throughout the Bay Area, living roofsas well as living wallsare (literally) sprouting up all over, as municipalities continue to hammer out environmentally thoughtful requirements for sustainable construction practices in new building projects. Its also driven by consumer demand as more people actively seek businesses and products that embrace environmental and sustainable practices.

John Loomis, a principal with the SWA Group in Sausalito, the landscape architecture firm that designed the living roof on the award-winning California Academy of Sciences (the project recently received a Global Award for Excellence from the Urban Land Institute ), also believes living roofs are becoming more common because they make it much easier to attain the coveted Leadership in Energy and Environmental Design (LEED) certified standards set forth by the U.S. Green Building Council. Loomis says many of SWAs clients set specific LEED certification level goals (platinum is the highest) when they begin projects, because they want to be able to advertise them as such.

Developers can command higher rents with buildings that are LEED-certified, he explains. Some cities are even mandating that new projects reach certain LEED levels, and one of the easier ways to get points is with effective storm water management and noise reduction. Living roofs are the perfect answer.

Living roofs have been near and dear to the hearts of environmentalists in Europe for nearly four decades now. Germany is credited with reviving the trend in the 1960s and, according to a study on living roofs conducted by Penn State University. more than 10 percent of all roofs in Germany are now green. The concept has been slower to take root in the United States, but interest is growing steadily.

Careful planning

It takes a good team to design and install an effective and efficient living roof. Its not like you can put down a plastic tarp, load it up with soil, scatter it with seed and hope for the best.

The SWA Group project at the California Academy of Sciences is a perfect example. The living roof became a part of the project after the architect, Renzo Piano of Renzo Piano Building Workshop (RPBW), fell in love with the treetop view from the roof of the former museum building and decided it was something people should experience. It was a natural fit for a science museum as well.

The architect specifically didnt want a shaggy, unkempt appearance for the living roof, Loomis says. Instead, there was a specific request for a more refined and consistent look to best represent the unique physical form of the structure. So SWA Group planted it with all native material indigenous to the Bay Area. A small observation deck sits in the middle of the roof, and SWA worked to make a special exhibit with nearly 50 different types of native plants around its perimeter. As the roof expands out from the center, fewer different types of native plants are used.

You have to make sure the roof is regenerative and adaptive. You have to have enough going on so you dont constantly have to replant things, he explains.

Their biggest challenge was that the roof sloped. Planting a green roof is fairly simple if its flat, but if its sloped, you have to make sure you build it to avoid landslidesyou have to make sure everything stays in place, Loomis says. This becomes less of an issue as the roof planting matures and the plant root systems begin to form mats.

The biggest plus to the Academy of Sciences living roof is its storm water management, Loomis says.

San Francisco has a shared sanitary and storm drain system, and storm water runoff from roofs going into the drains puts undue stress on a very old piping system, Loomis explains. The soil on a living roof holds moisture. When we looked at the rainfall data, we noticed we only had two months out of the year that were an issue as far as what the soil could hold. Six inches of soil will hold about four inches of water. The runoff from the roof is zero except for those two months. We determined we were holding more than 3.5 million gallons of water out of the storm drain. And what small amount does manage to run off goes into an underground chamber to recharge groundwater within the park.

Another benefit to the museums living roof is insulation. While some say living roofs help with both heating and cooling, Loomis says their impact is more to keep things cool. Theres no insulation value in wet soil, he explains.

Loomis believes that without the living roof, the California Academy of Sciences would never have reached LEED platinum certification, noting the structure has a heavy energy load as home to Steinhart Aquarium and the new Rainforest Biodome.

Other benefits

Green roofs have many ecological benefits in addition to reducing energy requirements for heating and cooling and helping to control storm water runoff. For one thing, they filter pollutants. According to the United States Environmental Protection Agency. living roofs retain up to 75 percent of rainwater, gradually releasing it into the atmosphere through condensation and transpiration, but keep air pollutants in the soil.

According to Loomis, living roofs are also popular because they combat whats called the urban heat island effect.

Roofs heat up, he explains. Most of the demand for green roofs in cities is to reduce the ambient air temperature. Traditional roofs soak up the sun and re-emit it as heat. By some estimates, cities are at least 7 degrees hotter than their nonurban neighbors. With large numbers of living roofs, temperatures can be lowered naturally. One perfect example is Chicago, which installed a living roof on its City Hall. On hot summer days, the temperature on Chicagos City Hall roof is between 25 and 80 degrees cooler than regular roof structures nearby.

Green roofs are also popular as habitats for animals, plants and insects that frequently encounter limited space in urban settings. According to London-based sustainability consultants Hilson Moran. living roofs have the biggest impact on biodiversity in cities because larger areas of roof space often mimic grasslands or other environments that can create their own ecosystems. Insects drawn to the rooftops entice birds and other animals. The roofs act as stepping stones, connecting urban areas with the countryside as birds and insects traverse.

Some use living roofs as a source of human food, planting fruits and vegetables for consumption. Its also believed that living roofs have an impact on both physical and mental health as people have more contact with nature.

Another benefit is sound insulation. Soil, plants and trapped layers of air absorb, reflect or deflect sound wavesmaking green roofs popular alternatives for those near airport flight paths. Finally, green roofs supposedly increase the lifetime of a roof, extending it as much as three times.

Since modern living roofs are relatively new, the jury is still out on that, Loomis says. Because the roof is protected from ultraviolet rays and doesnt experience thermal swings of expanding and contracting like a regular roof does, its said a 20-year roof will last 40 to 60 years. One thing you have to consider is that at some point, the waterproofing under the living roof will need to be replaced, which means youll have to remove the plants and growing mediumand that can be expensive. Currently, living roofs cost three to four times more than a traditional composite roof, $18 to $24 per square foot versus $6 to $8.

Of course, the larger the roof, the bigger the investment. Thats why Loomis says living roofs have more appeal when the building projects are smaller. And while you might think traditional roofing companies arent overly enthusiastic when it comes to green roofs, think again. The larger roofing companies have joined the movement and are providing pretty much everything you need for a living roofexcept the plants.

Going gold in Healdsburg

While no one has tried planting vineyards on green roofs (yet!), Loomis reports that several wineries in Napa and Sonoma are taking a serious look at investing in living roofs. His firm is currently working on projects for Staglin Family Vineyard in Rutherford, Paradise Vineyards on Highway 37 in Sonoma and Kenzo Winery in Napa Valley, Angwin Ecovillage and the St. Regis Hotel in Napa.

Two North Bay hotel projects also have embraced both living roofs and living walls as part of their design.

Currently under construction in Healdsburg, the new h2hotel on Healdsburg Avenue, south of Healdsburg Plaza, is a sister inn to the popular Hotel Healdsburg. Designed by David Baker + Partners Architects of San Francisco, the structure will feature an undulating green roof that Circe Sher, the propertys marketing and public relations director, describes as a fabulous design that will give added value to the overall experience [of our guests].

According to Sher, part of the impetus for the living roof was Hotel Healdsburgs ongoing effort to restore Foss Creek (the hotel is located on its banks). Weve been intimately involved with restoring the creek and have gained heightened awareness of all our waterways. Since the new hotel will be close to the creek, we felt a living roof would be helpful.

The h2hotel is striving for gold-level LEED certification, Sher says. Our decision to go with a green roof is really a combination of both aesthetic and environmental factors. Its an exciting signature design statement and offers a number of positive environmental attributes, she says.

A living roof filters rainwaterwater doesnt flow off the roof and cause erosion. Instead, it slowly percolates down, which lessens the impact on the local sewer system and creek, she says. It also provides a natural habitat for insects and birds, which adds value to the guest experience. And it adds some green space to the entire project and provides thermal and sound insulation. Well also be lessening our carbon footprint in Healdsburg by having a roof thats highly reflective, so it doesnt contribute to heat gain in the urban environment.

One third of the roof will be occupied by solar collectors for the hot water system and photovoltaic panels to supplement power use, Sher says. In fact, the overall project is a study in sustainability. The hotel will have an innovative heating and cooling system that follows the path of the sun, much like a sundial. Building materials include reclaimed wood and other recycled items from local sources (cutting down on the need for shipping, which uses too much energy), water bars on each floor with refillable glass carafes (no plastic bottled water), a bicycle program offering loaner bikes to guests to encourage less automobile use, drought-resistant native plants, recycling containers in each guest room, organic linens and eliminating bottled amenities (shampoo, conditioner, lotion and so forth) in favor of larger, refillable containers that are permanently adhered to the bathroom walls.

While many of these actions are part of the point system to get LEED certified, the hotel is going beyond LEED requirements, actively working on Foss Creeks restoration. Foss Creek is a steelhead trout habitat, Sher says. As part of h2hotels commitment to the community, it has partnered with two organizationsRussian Riverkeeper and Trout Unlimited to undertake ongoing projects beneficial to the creek.

Bardessonos green wall

The growing popularity of living roofs has also generated interest in interior dcor, pushing living walls into the spotlight. You can find a striking and highly acclaimed example of this unique architectural touch at Bardessono in Yountvillewhich is awaiting accreditation to become the only luxury hotel in the United States thats a platinum-level LEED-certified property.

Cristina Salas-Porras, director of guest experience, says the hotel design team was inspired by the many living walls theyd seen in Asia and Europe and wanted to do something similar at Bardessono. The idea worked well with the hotel managements core values, which looks upon cut flowers for massive floral displays, traditionally found in hotel lobbies, as a big no-no, Salas-Porras says.

We wanted something that was green and alive, something inviting, she says. So the hotel turned to San Francisco garden designer Flora Grubb. who created four 3-by-12-foot living panels that grace the contemporary hotel lobby.

The first challenge we had was there was no irrigation system available for the wall, Salas-Porras says. There also was no drainage. So Grubb conceived the idea of a tillandsia wall. Tillandsia, often called air plants, are part of the Bromeliad family. Their roots grow in the air, not the soil, and theyre maintained by twice-weekly mistings. Each plant is on a clip so it can be removed and watered or replaced if necessary.

Grubb also arranged the plants with plenty of space between them, giving each one its own starring role in the composition. The result is a beautiful display of plants that some say resembles fireworks or sea urchins.

The plant material is so interesting that our guests often ask us if its real, Salas-Porras says. Its become our signature piece. Its just beautiful and the colors change all the time. The walls have become a wonderful conversation piece for our guests, and the financial savings of not having cut flower arrangements is substantial.

Bardessono is the creation of Phil Sherburne of Seattle, who also owns two other hotelsWillows Lodge outside Seattle and the Inn at Spanish Garden in Santa Barbara. The 62-room hotel opened last February to rave reviews. In building his environmental temple, Sherburne only used salvaged California woods (bought within a 100-mile radius) and rusted steel. He installed a large garden and planted edible landscaping. Amenities were carefully selected and the hotel has no carpeting or drapery. Exterior shades keep each guest room cool or warm. The hotel uses organic linens and upholstery, and surfaces are either wood or polished concrete.

Phil is an environmentalist, Salas-Porras says, and this hotel is his model to show people that this is possible.

Interestingly enough, when it came to building the living walls, the biggest obstacle was convincing the hotel management it was a good idea. To be sure, it was a departure from the norm, Salas-Porras says, but now they love it and its been a huge source of pleasure for our guests.

And theres been another side benefit: The media coverage has been fantastic, says Salas-Porras. Theres a huge blog trail online when you search for Bardessono green wall, plus weve been featured in the New York Times and Sunset magazine. among others [see Hometown Luxury, March 2009 ].

Getting there

If youre interested in a living wall or roof for your home or business, there are certain things those we interviewed for this story highly recommend.

Consider the structure. If youre using an existing building, make sure an engineer evaluates the building and determines whether or not it can sustain the load.

Check city requirements for code compliance and building permits.

When hiring a contractor or engineer, check with green-building associations first. Their members are more likely to have the qualifications and expertise needed to undertake the job.

Be sure to consider the environment, particularly in the case of living walls. Work with someone whos confident and who takes heating and cooling into consideration [when designing the wall], says Salas-Porras.

Find someone who understands what vegetation is the most effective, requires the least amount of maintenance and lasts the longest.

As living roofs and walls grow in popularity, its likely well see more spring to life in the North Bay. And if maintenance is as easy as some experts profess, many more of us will be singing along to that old song recorded years ago by The Drifters Up On the Roofespecially the part that says, Right smack dab in the middle of town/Ive found a paradise thats trouble-proof/Up on the roof.

MONTREAL — This looks like the last place you’d want to grow a garden. But several storeys above Atwater Ave. and de Maisonneuve Blvd. on a concrete rooftop wedged between ventilation systems and chimney stacks, bees buzz and late-season strawberries and cherry tomatoes ripen. A new crop of lettuce shows signs of green in a row of giant pots, the last hurrah before fall’s frost.

Welcome to Dawson College’s Rooftop Garden Project, which has turned four desolate expanses at its campus downtown into vegetable gardens lush with fruits and vegetables.

Student and staff volunteers plant and tend the gardens, which grow in raised beds and recycled containers. One crew of 100 teachers and students planted such cool-weather crops as lettuce, spinach and Swiss chard during a work bee marking Earth Day back in April, before the spring semester ended. Another team of 12 interns, from Dawson and Concordia University, took over watering and weeding duties during the summer, and at the start of the current fall semester, yet another team of student-gardeners planted more lettuce and continued the weeding and watering.

Now, every Thursday from 2 p.m. to 4 p.m. the fruits (and vegetables) of their labours are for sale at a weekly on-campus harvest market, which runs from May through October.

Up On the Roof

Anna-Liisa Aunio, the sociology and environmental studies professor who runs the Rooftop Garden project, says she has been bowled over by how popular the gardens are among the college’s decidedly urban students and staff. She always gets a long list of volunteers willing to work in the garden. On market days, there are lineups of shoppers at the table and sometimes everything sells out within 15 minutes.

The garden and its bounty appeal to different people for different reasons, Aunio said. There are students who are interested for environmental reasons. Others grew up in families where parents and grandparents tended backyard vegetable plots and they come to help out of nostalgia. And there are those who care nothing about getting their hands dirty and love the garden for its fresh, local produce and the sheer joy of buying fruits and vegetables that grew just steps away.

These gardens, just winding up their third season, are part of Dawson College’s hands-on way of driving home the lessons of sustainability and community-building taught in its environmental studies program. They are also a way of connecting the students at large with the food they eat. Indeed, students eating lunch in Conrod’s, the seating area beside the cafeteria, have a view right onto the interior courtyard where raised-bed gardens with Swiss chard, six varieties of heirloom tomatoes, beans, sunflowers and red-leaf lettuce grow on a cement surface above the gym.

The rooftop gardens have also been supplying Dawson Dining, which provides free vegan lunches to students every Monday, Wednesday and Friday, with fresh supplies of campus-grown kale, the most popular vegetable among students this semester.

In one garden, located on a fourth-floor roof above the H wing, tomatoes, strawberries and bell peppers are spilling out of their 15-gallon geotextile grow bags ­— laid out with plenty of room between them, to allow air to circulate. Unlike conventional planters, which tend to become rootbound, these fabric containers allow the plants to flourish. There are pots of newly planted lettuce, cool weather crops that can stand the cooler fall temperatures.

Honey bees buzz about, inhabitants of two new hives the Rooftop Garden project has brought in, under the guidance of urban beekeepers from Alveole to help pollinate plants this high up above the city. With any luck, there will be honey to sell at the harvest market before too long.

There are myriad challenges to growing food in this extreme downtown environment. The wind up on the higher rooftops can be fierce, and in the lower-level gardens, squirrels are a chronic nuisance. Drought is a problem, too, as it is in all container gardens. The Dawson gardeners have learned to leave plenty of space around the pots to allow for greater air circulation, which reduces the risk of mould and mildew and other diseases. They have built their own self-watering containers using plastic recycling bins, yogurt containers and PVC pipe, even cast-off election posters to keep plants moist but not soaking wet.

“We are using this a living laboratory,” Aunio says, surveying the drying leaves of the Swiss chard that fared poorly in pyramid-shaped planters that proved too shallow. One team of students is collecting data for a research project that compares the effect of location on plants’ growth. Another is examining the benefits of rain water over tap water.

Dawson’s Rooftop Garden project, which is funded by the CEGEP, also looked to outside partners for financing and hands-on help building and growing the garden. It partnered with Urban Seedling, the Montreal company that helps city dwellers grow vegetable gardens for supplies and expertise, and solicited funds from a non-profit organization that promotes urban agriculture in Quebec colleges and universities.

Tereska Gesing, co-founder of Urban Seedling, says Dawson’s gardens are worthwhile on many levels. Growing gardens in a dense downtown area helps cool the area and mitigate the polluting effects of urban heat islands, which are created when asphalt and concrete absorb the energy of the sun and raise temperatures. What’s more, she said, the opportunity to dig around in the dirt and grow their own food is also the best way to educate young adults who are just beginning to shop and cook about eating sustainably.

Aunio, who is in the garden getting set for a weed-pulling marathon on one of the last balmy days of summer, said the best part of growing vegetables right on campus is that it brings the lofty and important ideas she teaches in her environment studies classes closer to home.

“We tend to think that the environment is over there somewhere. But it’s right here,” she says, carrying a harvest of cherry tomatoes in her hoodie. “The garden has helped us drive that point home.

“Even people who said they weren’t interested in urban agriculture are lining up to buy our kale and Swiss chard. And with that, their perspective changes.”

MONTREAL — This looks like the last place you’d want to grow a garden. But several storeys above Atwater Ave. and de Maisonneuve Blvd. on a concrete rooftop wedged between ventilation systems and chimney stacks, bees buzz and late-season strawberries and cherry tomatoes ripen. A new crop of lettuce shows signs of green in a row of giant pots, the last hurrah before fall’s frost.

Welcome to Dawson College’s Rooftop Garden Project, which has turned four desolate expanses at its campus downtown into vegetable gardens lush with fruits and vegetables.

Student and staff volunteers plant and tend the gardens, which grow in raised beds and recycled containers. One crew of 100 teachers and students planted such cool-weather crops as lettuce, spinach and Swiss chard during a work bee marking Earth Day back in April, before the spring semester ended. Another team of 12 interns, from Dawson and Concordia University, took over watering and weeding duties during the summer, and at the start of the current fall semester, yet another team of student-gardeners planted more lettuce and continued the weeding and watering.

Now, every Thursday from 2 p.m. to 4 p.m. the fruits (and vegetables) of their labours are for sale at a weekly on-campus harvest market, which runs from May through October.

Anna-Liisa Aunio, the sociology and environmental studies professor who runs the Rooftop Garden project, says she has been bowled over by how popular the gardens are among the college’s decidedly urban students and staff. She always gets a long list of volunteers willing to work in the garden. On market days, there are lineups of shoppers at the table and sometimes everything sells out within 15 minutes.

The garden and its bounty appeal to different people for different reasons, Aunio said. There are students who are interested for environmental reasons. Others grew up in families where parents and grandparents tended backyard vegetable plots and they come to help out of nostalgia. And there are those who care nothing about getting their hands dirty and love the garden for its fresh, local produce and the sheer joy of buying fruits and vegetables that grew just steps away.

These gardens, just winding up their third season, are part of Dawson College’s hands-on way of driving home the lessons of sustainability and community-building taught in its environmental studies program. They are also a way of connecting the students at large with the food they eat. Indeed, students eating lunch in Conrod’s, the seating area beside the cafeteria, have a view right onto the interior courtyard where raised-bed gardens with Swiss chard, six varieties of heirloom tomatoes, beans, sunflowers and red-leaf lettuce grow on a cement surface above the gym.

The rooftop gardens have also been supplying Dawson Dining, which provides free vegan lunches to students every Monday, Wednesday and Friday, with fresh supplies of campus-grown kale, the most popular vegetable among students this semester.

In one garden, located on a fourth-floor roof above the H wing, tomatoes, strawberries and bell peppers are spilling out of their 15-gallon geotextile grow bags ­— laid out with plenty of room between them, to allow air to circulate. Unlike conventional planters, which tend to become rootbound, these fabric containers allow the plants to flourish. There are pots of newly planted lettuce, cool weather crops that can stand the cooler fall temperatures.

Honey bees buzz about, inhabitants of two new hives the Rooftop Garden project has brought in, under the guidance of urban beekeepers from Alveole to help pollinate plants this high up above the city. With any luck, there will be honey to sell at the harvest market before too long.

There are myriad challenges to growing food in this extreme downtown environment. The wind up on the higher rooftops can be fierce, and in the lower-level gardens, squirrels are a chronic nuisance. Drought is a problem, too, as it is in all container gardens. The Dawson gardeners have learned to leave plenty of space around the pots to allow for greater air circulation, which reduces the risk of mould and mildew and other diseases. They have built their own self-watering containers using plastic recycling bins, yogurt containers and PVC pipe, even cast-off election posters to keep plants moist but not soaking wet.

“We are using this a living laboratory,” Aunio says, surveying the drying leaves of the Swiss chard that fared poorly in pyramid-shaped planters that proved too shallow. One team of students is collecting data for a research project that compares the effect of location on plants’ growth. Another is examining the benefits of rain water over tap water.

Dawson’s Rooftop Garden project, which is funded by the CEGEP, also looked to outside partners for financing and hands-on help building and growing the garden. It partnered with Urban Seedling, the Montreal company that helps city dwellers grow vegetable gardens for supplies and expertise, and solicited funds from a non-profit organization that promotes urban agriculture in Quebec colleges and universities.

Tereska Gesing, co-founder of Urban Seedling, says Dawson’s gardens are worthwhile on many levels. Growing gardens in a dense downtown area helps cool the area and mitigate the polluting effects of urban heat islands, which are created when asphalt and concrete absorb the energy of the sun and raise temperatures. What’s more, she said, the opportunity to dig around in the dirt and grow their own food is also the best way to educate young adults who are just beginning to shop and cook about eating sustainably.

Aunio, who is in the garden getting set for a weed-pulling marathon on one of the last balmy days of summer, said the best part of growing vegetables right on campus is that it brings the lofty and important ideas she teaches in her environment studies classes closer to home.

“We tend to think that the environment is over there somewhere. But it’s right here,” she says, carrying a harvest of cherry tomatoes in her hoodie. “The garden has helped us drive that point home.

“Even people who said they weren’t interested in urban agriculture are lining up to buy our kale and Swiss chard. And with that, their perspective changes.”


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