11 February 2009

Blue Roofs

the fifth façade – beautiful affordable eco-roofs

Owen Rose www.ecosensual.net
The human body is largely composed of water and its intimate connection to the blue planet does not stop with the flush of a toilet.
Often a source of grief; too much or not enough, water is both a visible and invisible concern for cities. not only do we have to find a source, clean it up for potable use and then distribute it, but we also have to dispose of it. Black or grey, waste water treatment is a costly and difficult task. Think of cities such as Halifax and Victoria that dump their untreated wastewater directly into the ocean. Although Montréal has a large sewage treatment plant a the east end of the island, the city still averages about 22 discharges of untreated sewage directly into the Saint Lawrence River each year. When it rains too much the combined storm and sewer system cannot process all of the water from our houses, hospitals, factories, rooftops and polluted streets. Thus the problem is passed on to the fishes, whales and other cities downstream.
Now that we have started to face the growing threat of environmental problems such as urban heat islands, air, water and noise pollution as well changing weather patterns, ecological building criteria such as the LEED (Leadership in Energy and Environmental Design) green building rating system have encouraged the construction and design of more ecologically sustainable buildings. In the six LEED categories, water management takes on several forms: one is a vegetated roof.
Instead of installing deserts of tar and gravel on our roofs, more and more institutions, businesses and homeowners are opting to grow fields, gardens and vegetable patches on them. Aside from their obvious beauty, green roofs offer natural cooling, a greater lifespan and better rain water management. They retain about 50% of fallen rain (returning water to the atmosphere bypassing the city's sewer system). The other 50% will still find its way to the drain, but the return of this water is delayed, which helps city infrastructure manage water levels during downpours and intense rainfall.

What about Leaks?
Modern green roof experience started in Germany fore than forty years ago, and the waterproof aspect of such roofs is no longer a major concern. In North America, quality waterproofing membranes are on the market, capable of withstanding the constant humid environment of green roofs. Also, earth cover protects the membranes from large day to night temperature fluctuations and the sun's ultraviolet rays, both of which break down conventional roofs over their 20-year lifespan, whereas green roofs should last about twice as long. The real challenge is in created the lightest technology possible so that plants are still able to survive summer droughts and, more importantly, cold Canadian winters.

Green roofs on New or Existing Buildings?
In the deluge of new interest in green roofs, some owners of existing flat-roofed structures have looked at retrofitting an extensive green roof on their buildings; however, not all existing flat roofs are able to support the weight of even the lightest green roof assemblies. To study residential green roof retrofit possibilities, the Montréal Urban Ecology Centre built a demonstration project on top of an existing 100-year old Montréal duplex in 2005. the project included the complete reconstruction of the roof structure followed by the installation of a 15cm thick extensive roof. Half of the project cost was related to the structural retrofit. Although successful, the project was expensive.

In the case of new construction, extensive green roofs are much more economical and usually cost two to three times the amount of normal roof standard roofing systems; however, these green roofs should also last twice as long. With the natural renewal of a city's building stock, the widespread installation of green roofs with new construction would transform a city's roofscape over time. In 2006, the City of Toronto adopted public policy to encourage green roofs through urban planning and financial subsidies [www.toronto.ca/greenroofs/index.htm].
More and more building professionals and contractors are learning about green roof construction. to facilitate the learning process the Urban Ecology Centre [www.urbanecology.net] published two green roof reports (in French) in 2005 and 2006. the first report, Toîtures vertes a la montréalaise, was a 100-page introduction to green roofs for the southern Québec climate with a survey of green roof experiences in Québec and around the world. The second report, Projet-pilote de toît vert, documents the demonstration project form its initial planning to ongoing plant maintenance. It includes many photos and illustrates the project's costs, materials, earth and plant choices, the role of each team member. the Canada Mortgage and Housing Corporation (CMHC) has also published reports relating to green roofs [www.cmhc-schl.gc.ca].

Team Effort
The basic construction team for a green roof includes the client, architect, structural engineer, green roof supplier, general contractor and roofing subcontractor. Depending on the extent of the project, a landscape architect or a horticulturalist could also be part of the team. there are more and more green roof suppliers in Canada. Technically, the construction of a green roof is not that difficult; however, due to the additional weight, a structural engineer should always be consulted. Ultimately the success of a project is determined by the correct choice of plants and substrate thickness given the roof's particular microclimate and the client's desired aesthetic. the true test of a green roof is whether the plants are able to survive three consecutive winters; so, when a new green roof technology appears, it is always a good idea to ask if it has at least three years of proven success and/or a good warranty.

Green Roof Composition
The green roof system can be installed once the roof structure has been properly designed and the appropriate roofing membranes have been applied. the system varies from one supplier to another, but usually contains a number of items such as an anti-root membrane, water drainage panels, a geotextile and specially formulated green roof light earth substrate. The weight of the earth holds the system in place by gravity.
Now the gardening begins! The most appropriate categories of plants for extensive green roofs are wild grasses, wild meadow flowers and sedums (waxy plants). the ecological goal is to favour indigenous plants, but the final choice depends on the chosen green roof technology and the roof's planned use. A number of institutional extensive projects in Montréal have used clover for its low-cost and tenacious character. Each green roof supplier is capable of furnishing information about the appropriate choice of plants and their aesthetic impacts. The installation of an irrigation system also depends on the type of roof and choice of plants. The more ecologically-oriented the roof, the less likely that it will need an irrigation system. In cities, irrigation of green roofs and gardens uses municipal water. Rain and/or grey water recuperation and indigenous landscaping strategies can help reduce summertime demand for city water resources.

It's Alive!
Unlike a normal roof that most of us tend to forget,a green roof does require regular maintenance. For an extensive ecological roof, the maintenance is minimised to about six times a year from spring through to autumn. This requires inspection of the roof drains to make sure that they are clear of debris, trimming the plants in spring and periodic weeding. If the roof does not have a built-in irrigation system, even the hardiest of ecological roofs may need additional irrigation during intense summer heat waves. Much of the roof's maintenance will depend on how the roof is used, the plants that have been chosen and the owner's gardening habits. Residential green roofs can also be used for recreational gardening.
Loft owners in Montréal have also invoked the idea of an urban cottage where the roof may include an outdoor bedroom, shower, summer kitchen and patio surrounded by a roof-top meadow and views of the city. For the building owner, green roofs increase building value and create a personal urban oasis. For the larger community, green roofs reduce the load on a city's water infrastructure and help to moderate urban temperatures. Clearly, green roofs not only benefit individuals, but they also benefit our neighbourhoods and our cities. the fifth façade has never shown so much potential.

Rose, Owen. 'Blue Roofs' On Site review, no. 17 Spring/Summer 2007
©Owen Rose and On Site review

10 February 2009

Soggy Bottom Architecture

worried about rising sea levels? Go to the Netherlands — they have lots of experience with these things
Paul Whelan, illustration: New New York by Hugo Arriojas
According to a pair of studies published in the journal Science, global warming has already committed our planet to rising sea-levels. Jonathan Overpeck, an earth scientist at the University of Arizona in Tucson who co-authored both studies, says that the sea level will rise at rates of up to a metre per one hundred years – and it could go faster.
Humans are vulnerable because we build most of our cities in low coastal areas. The recent example of New Orleans and the ongoing struggle between the Netherlands and the sea are reminders of our future reality. We know that the water is rising, so what can we do? The obvious answer is to reduce our dependence on carbon ... but humans are catastrophically bad at taking preventative actions. Inevitably we will have to adapt to global warming and all its consequences, including higher sea levels.
However, there is a continuum of available responses ranging from holding back the water, making or buildings float, or simply doing nothing.

Beavering Away
If we decide to fight the seas and hold the water back, the Netherlands offers planning, engineering and political lessons Their extensive systems of dykes, dams and drainage strategies are designed to keep land below sea level dry. Rising sea levels threaten the entire country.
Recently a Dutch landscape firm, H+N+S, have proposed a new response to the triple threat of rising sea levels, subsiding land and increasing rains. To dampen the impact of ever-increasing storm surges, H+N+S propose selectively channelling the water behind the defences. H+N+S advocate catchment systems for fresh and salt water and reservoirs for excess rainfall. This strategy will require relinquishing land so strenuously won from the sea. The landscape will change from traditional farmland with water channels and ditches to one of raised lakes and reservoirs – a kind of non-sensical contour map. However, it could be the only way the Netherlands can save its country.
Regardless of the engineering and planning, the Dutch rely on a highly centralised government to construct and maintain their sea defences. Their system of participatory and centralised democracy is a political anomaly and I fully expect that fighting the sea would more likely result in less-friendly autocratic government.

Happily, buildings can float. there are two models for floating foundations. the Canadian model is based on the diving raft with concrete poured around polystyrene. These structures are unsinkable, but tend to be less stable for non-square geometries. Not surprisingly, the Dutch have been experimenting with floating buildings. Based on the river barge, Dutch technology consists of a floating concrete container in which the lower level becomes an underwater basement. Waterstudio Architects of the Netherlands have designed floating houses and are currently developing a 25-storey floating office tower and courtyard housing prototypes.
To date, floating buildings depend on nearby dry land for services or are anchored with mooring poles that also provide an umbilical connection for services. Without sea defences, floating buildings will be extremely vulnerable to increasingly violent storms, except where large expanses of newly inundated lagoons could provide a storm-damping environment in flat low-lying areas. Floating buildings could be effective in marshy delta areas that are already threatened by rising waters.

Do Nothing Romanticism
Doing nothing may ultimately be the most romantically compelling response to rising sea levels. Venice, a city that accepts its regular inundations, may offer the most clues for the benign-neglect approach. As Venice slowly disappears, many other cities could take its place as a magical tourist destination. Imagine gondoliering through a New York transformed into a city of canals and skyscrapers. However, a deliriously wet New York will ultimately require serious design to ensure the right level of submersion. At the very least, infrastructure such as the subways, potable water, power and sewage would have to be re-engineered.

Saving our sinking sea-level cities will be an expensive undertaking. The capital needed to re-engineer an entire city will be scarce as businesses move away to drier and higher ground. Whole districts of the city will elegantly decay as the water laps at their second floor windows. We live in an era where financial markets dictate settlement form. As in Venice, it is quite likely that at some tipping point, the rich will abandon the coasts for safer inland settlements, leaving the poor to cope with their deteriorating coastal cities.
In any built response to rising sea levels, infrastructure and its maintenance will be a significant challenge. What we humans lack in intelligence we sometimes compensate for by cleverness. Perhaps we will be making floating cities anchored to the atlantan ruins of our submerged cities. Maybe our future will be a combination of Futurism fantasy and Disney picturesque.
Whelan, Paul. 'Soggy Bottom Architecture' On Site review, no. 17 Spring/Summer 2007
©Paul Whelan, Hugo Arriojas and On Site review

06 February 2009

Dubai Culture

Jumeirah Lake Towers, New Dubai UAE
Ski Dubai at the Mall of the Emirates, Dubai UAE

photos by Barbara Flanagan-Eguchi

Real Eguchi
It seems to me that there is an unhealthy disconnect between the cultural heritage of Dubai and the western culture it is embracing. When I say unhealthy, I mean the resulting consequences for people and the local environment that stems from recent development. I hope Dubai is not just about the culture of greed. Let’s reflect upon our own beliefs and values, since development in Dubai may very well be congruent with what we do here, except more intense at the moment.
Eguchi, Real. 'Dubai' On Site review, no. 18 Fall 2008
©Barbara Flanagan-Eguchi, Real Eguchi and On Site review

04 February 2009

Beach as Model

enduring urban images

Copacabana is more than a neighbourhood. It is the limit between the city and local enclosures. Copacabana moves between the sensorial, the externally visible, offered through forms, colours, architecture, traffic and people, and from the other side, the spaces are reduced to the invisibility of everyday life where thousands of people submerge, anonymous faces stamped by unknown life. —Wilson Coutinho

The aerial view above is from Manchete, a Brasilian popular news magazine from the seventies, which we, spmb_projects, use almost as a logo, as a central reference for our practice. The beach engages public space in the most radical sense, where territoriality is blurred by a new possibility of spatial negotiation. It is also one of our favourite spaces in the world. Here the inhabitants of different backgrounds, cultural formation, racial roots and social classes share one same landscape in relative harmony. The beach becomes the image of the ideal urban social equaliser – a spatialised democracy in a sense. Other qualities that constitute this ideal land/urbanscape are: warm air, natural and human soundscapes, soft surfaces, views, informal infrastructures – beach vendors, ocean water, pick up soccer and kiosks; formal infrastructures – abundant transportation systems, boardwalks, health and safety stations, public washrooms, life guards, restaurants and bars, security, and large events like concerts, parades or celebrations.

The iconic design of Roberto Burle-Marx was completed in 1970, and Copacabana was redefined through the expansion of the public space by stretching the surface of the beach and the promenade through the use of traditional Portuguese mosaic paving stones, creating the now famous pattern. Based on the achievement of Copacabana beach as an exemplary case of engaging urban design, and for its renowned quality of an urban environment, this experience could even suggest a new field of exploration that we refer as Beach Urbanism. It serves us as a model for the ways we practice in public space: the beach as an urban infrastructure.

spmb_projects. 'Beach as Model' On Site review, no. 18 Fall 2008
©Eduardo Aquino, Karen Shanski and On Site review

03 February 2009

Form and Settlement

the social construction of landscape

Elizabeth Shotton
North Atlantic Rim (NAR) Research Collaborative: University of Science and Technology in Trondheim, Norway. Dalhousie University in Halifax, Canada. University College in Dublin, Ireland. Academy of the Arts: Architecture and Design in Reykjavik, Iceland.

NAR's series of cross-cultural studies of coastal settlements on the north Atlantic started in 2004 with initial drawing and documentation studies of coastal landscapes and settlements in Norway and Ireland. It continued the following year in Iceland, and concluded the first phase in Nova Scotia in 2006.

The project has examined natural landscapes, altered landscapes, historic and contemporary building responses to these conditions, and the relationship between material resources and building form. North Atlantic coastal landscapes face significant development pressures and environmental threats to their fragile ecosystems, landforms and settlements. Conte drawings from the scale of landscape to building form and detail, scaled aerial drawings of each region and site photography have formed a basis for comparisons, identifying salient issues of culture and settlement patterns, landscape and its relevance to built form.

NAR's project parallels Richard Saul Wurman's work with design student at the University of North Carolina, later made into a small book called Cities: Comparisons of Form & Scale (1963). His representation of city form in sand castings insipred NAR's study of landscape and settlement in drawings. Wurman's thesis was that 'the healthy existence of cities is the degree to which the beginnings of a particular city is apparent'. NAR's focus reaches further back to the primacy of landscape to understand its critical relevance in shaping the form of human culture and settlement. While Wurman's work responded to the underlying pressures on city development during the mid- to late-twentieth century, environment is key to our present and future evolution, allied to current issues of sustainability.

Robert Thayer, in Gray World, Green Heart: Technology, Nature and the Sustainable Landscape, proposes that 'surface versus core' is one of the most fundamental ways to understand landscape. Describing the ever-widening dislocation between these two, he proposes that surface values are based on what is in front of us. As a visually-trained profession we see the surface condition of landscape, and work to reveal its poetic beauty through our remaking of its surface through building. Difficult to achieve and admirable when realised, it is the manner in which young architects are trained and old architects work. However, it does not engage the core.

Core values are those hidden conditions of the land, its ecological and material processes – the operative level of landscape. Re-linking those processes construed as natural and those construed as made, challenges the surface-core dichotomy with a more holistic picture of continuity and interdependence – landscape as the thing that hold us. Sustainability as a reading of core, of processes and interrelationships, was commonplace until technology and industry severed this understanding.

However, recent ecological consequences have reached a crisis, revealing once again our interdependence with the land. This critical immediacy between landscape and building is the subject of NAR's research — to understand how intimately architecture can be informed by its place by comparing four places of similar but unequal landscapes, with four similar but unequal legacies in building.

Ireland, Norway, Iceland and Atlantic Canada share some surprising landscape alliances. Although Norway has steep mountain ranges and deep fjords, its habitable coastal lands strongly resemble the others. Each place is dominated by coastline, Iceland and Ireland as islands and Nova Scotia and Norway as peninsulas. The Atlantic Ocean tempers the environment each, maintaining green landscapes of small valleys and hills interrupted by rock outcroppings and cliffs. It also inform the industry and culture of these regions.

Subtle distinctions in form, built or unbuilt, the relationship to resources, climate and culture become manifest when studied through the discipline of drawing. When various research interests are brought to bear on the drawing project, from the relationship between perception, representation and design, to environmentally-driven foci on material resource management and use in architectural practice, a diversity of cultural, material and formal readings emerge. excerpts from students' notes demonstrate this vividly.

Cultural and personal backgrounds of the participants have enriched these studies. Perceptual biases both influence the reading of the terrain under investigation, and recast one's own culture in comparison. Legacies of physical and cultural alteration to the landscape that come from inhabitation become not only explicit but also often poignant when coupled with the shared experiences of a cross-cultural research team.

If limited only to the yearly exchange of ideas among students and staff, the project has value enough as it gives new insights into architectural form, space making and cultural meanings.

The second phase of the NAR project will revisit the four countries, expanding its base of documentation and including built experiments.

Shotton, Elizabeth. 'Form and Settlement' On Site review, no. 17 Spring/Summer 2007
©Elizabeth Shotton and On Site review