16. |
Gardens in the air
21 February 2014, BT Invest Blog (www.btinvest.com.sg/blogs/) |
We celebrated ‘Fifty Years of Greening Singapore’ in 2013. This is the success of the ‘City in a Garden’ vision that was kicked off by Singapore’s first prime minister, Lee Kuan Yew, in 1963.
Since then, we have progressed beyond planting trees at ground level such as along the pavements, at our home gardens and in parks. Buildings with sky gardens are now a common sight across Singapore. Within the last decade, new developments have added a lot of greenery to our skyline. If I recall correctly, commercial buildings in the city centre featuring large sky gardens were led by One Marina Boulevard (also known as NTUC Centre) and One George Street were they were completed in 2004. And after the BCA Green Mark Scheme was introduced in January 2005, many developers incorporated sky gardens in their projects as partial fulfillment towards the Green Mark assessment.
Developers welcomed and made full use of several incentives which led to further greening of our buildings. For example, up till 31 December 2008, the Urban Redevelopment Authority (URA) used to give exemptions on the Gross Floor Area (GFA) for planter boxes in order to “encourage residents living in flats and condominiums to provide some vertical greenery to help create visual relief to our high-density living environment.” With the GFA exemption, developers generously incorporated planter boxes in their projects as they can sell the extra floor space to buyers.
However, today, if we look at the condominiums that were built with planter boxes, we might see that more than half of the units do not make use of the planter boxes for plants. As a property agent and real estate consultant, I have seen many apartments that have planters. While some planters are indeed filled with pots of plants, most planters attached to balconies are covered up and used as additional floor space. Some leave the planters empty and some deck up the planters as storage space.
Many planters are also less than accessible, built outside of bathroom windows and on the exterior of bay windows. Difficult to access planters and ledges pose challenges for maintenance and upkeep of the plants. And what about the occasional cleaning of the planter boxes? For the high rise planter boxes to be well maintained, additional safety precautions might be required too.
Figure 1: Floorplan of an 807 sqft apartment with planter boxes that might be a challenge to access and maintain.
The decision by owners and tenants to use the planter boxes for the original purpose intended or not partly depends on the ease of accessibility too. In Figure 1 in the previous page, with the exception of the planter in the balcony (which is frequently repurposed as extended balcony space), the other planters are not exactly easy to use. We might surmise that why most of the planter boxes in the apartment block have been left empty is due to issues of accessibility and maintenance.
Figure 2: A condominium block where most planters are left empty.
Figure 2 shows a recent photo of a development where only one apartment’s planter box was used. Where planters are not evenly utilised across a whole block, the façade looks patchy and that defeats the purpose of vertical greening. To make matters worse, if the under-utilised planters were not covered up or regularly cleaned to prevent clogged drainage and ponding, they might become breeding grounds for mosquitoes. This example of a condominium block with its under-utilised planter boxes is no exception. Planters in strata-titled offices, industrial units and residential units are recent additions to our real estate scene.
As the authorities wanted to discourage boring, flat building façade designs, the developers were allowed some free GFA for bay windows, planters and balconies. Recesses, protrusions, cantilevered trellises, balconies, ledges and vertical modulated features all add to the articulation of building façades. These are well and good for buildings which belong to a single owner who will manage the entire space including all the secluded nooks and corners. But if the units within a building belong to individual owners, the standards of upkeep, maintenance and cleaning of periphery areas, such as planter boxes, would vary widely. Poorly designed, inaccessible planter boxes and ledges are likely too be under-maintained.
Many city dwellers are also not keen on planting and are unhappy that the space they paid for cannot be converted for other use (such as extending the balcony or living room). The objective of the authorities, in allowing planters to be exempted from GFA to encourage vertical greening of Singapore, was therefore not met. URA has withdrawn the GFA exemption for planters (and bay windows) within strata units since 1 January 2009.
Despite that withdrawal of exemption, planters still feature in new developments, but the GFA of the planters within each strata unit now count towards the utilisation of the plot ratio. Going forward, it would be interesting to monitor the standards of upkeep and deterioration of planters in strata developments. Would maintenance costs increase compared to apartment units without planters?
On a larger scale of vertical greening, would be sky gardens and garden walls. Within the last ten years, most of the high rise projects of plot ratio 2.0 or more feature sky gardens in their common areas say on the fourteenth floor, twenty-fourth floor or thirty-forth floor (our superstitious disdain for the number 4 makes apartments on these levels less desirable to investors and tenants and therefore, these floors are often designed as sky gardens with facilities such as BBQ pits, function rooms, gyms and jacuzzis.). This applies to single owner and strata-titled office and industrial buildings as well.
The aesthetics of the vertical greening also vary. Some of the landscaping look overly profuse while others look like a hodgepodge of browns amid the greens. Sky gardens and garden walls on the façades of buildings could be visually ugly or look scruffy and under-maintained if the plants were damaged due to extended dry periods or wet periods. But the issue of aesthetics is a subjective matter and depends on what pleases an individual.
My key concerns revolve around maintenance and, within our tropical climate, the creatures that may thrive. One attractive, but not so obvious, feature of moving into a brand new high-rise apartment is that the tenant can enjoy a few years of hygiene comfort generally free of pests. Take The Sail at Marina Bay for example. It is a strata-titled condominium that was completed in 2009 and it has little, if any, sky gardens and planters. Today, one would be hard pressed to find, say within apartments above the fifteenth storey, the usual friendly neighbours such as lizards, mosquitoes, cockroaches, worms, spiders, beetles, flies, etc. Unless these crawlies were ‘imported’ by the tenants and then a few of these immigrants somehow managed to build their nests and breed to a nuisance level within the apartments that are say, ten floors or more above the facilities level.
Today we see many new developments launched with sky gardens as a selling feature. Garden walls and sky gardens are incorporated up to the uppermost floors of buildings, sometimes even on the roof tops. And where there may be sky gardens on a high floor (say twenty-fourth floor) and an intermediate floor (say fourteenth floor), then the landscaping of these gardens naturally include ‘imported’ pests. So, in my opinion, the key selling point that one is never more than five storeys away from a sky-garden-facilities-level is not exactly that attractive once we have to contend with the possibility of additional fumigation in and around the apartments.
For many expatriates from temperate countries, living with insects year-round is not a welcoming notion. While the building’s green façade may look attractive to prospective tenants, these tenants might not feel at ease when they are living within the building.
Crawlies aside, sky gardens, garden walls and green roofs do bring advantages in terms of providing shade and insulating buildings from our tropical sunshine. Plants have a cooling effect through dissipating direct heat including reflected heat within our concrete jungle. Vertical greening will reduce energy consumption during hot days. Green roofs that are well constructed also extend the lifespan of the roofs by limiting the daily temperature extremes and expansion/contraction, the degradation of roof material caused by UV rays and slowing down disintegration, cracking and splitting. There is also the advantage of having fresh oxygen close by.
In this day and age of ‘Save Our World’ and environmental consciousness, many articles have been published about the positives of vertical greening. However, there is little mention of the negative aspects of sky gardens, green roofs and garden walls in most of the literature available on the internet. While we read so much about the long-term good of vertical greening, I hazard a few points below on several potentially negative aspects.
In addition to the disadvantages of crawlies that might be introduced by sky gardens, the long-term cost of maintenance and care required may not be well understood. The cost and the effort required to maintain sky gardens and garden walls could be under-provided, especially in strata-titled projects where the Management Committee may be made up of members who have little experience with sky gardens and garden walls. For example, in fumigating the common areas, the larger and obvious areas are well sprayed but pockets of less-accessible sky gardens and five-metre high garden walls attached to mid-air trellises may be missed out.
A high garden wall that is a challenge to maintain: pest control, watering the plants and keeping them alive and thriving, pruning, etc. It is also a challenge to reach the top planter box because the ground is stepped and not level, making it difficult to place normal ladders.
The design of sky gardens, garden walls and green roofs must include detailed considerations for maintenance over a twenty- or thirty-year period — are extra ladders required? Safety railings and anchor points for harnesses of the horticulturist? Are the planter trays and cells of the garden wall easy to replace? Are the plants easy to water and fertilise?
These considerations are especially important for strata-titled buildings managed by committees whose members change periodically. These committees may also change their service contractors periodically. With sky gardens and green roofs, the loading on the building structure is increased with the weight of the plants, gravel and water. Small trees and shrubs may need to be properly anchored and secured to prevent destruction by strong winds and heavy storms. The upfront capital expenditure for the developers could increase and be passed on to buyers.
The watering of plants requires a well-designed and effective drainage system that can allow for additional run-offs especially during periods of heavy rains in Singapore. Drains and drainage pipes should be designed for easy checking, for easy maintenance and for removal of clogs. A good design allows the gardens to drain, yet retain sufficient water for the plants without leaving pools of stagnant water. A water-clogged spot that is not checked for a couple of days could become new breeding ground for mosquitoes.
The need for good drainage goes hand-in-hand with solid waterproofing. Depending on the extent of the foliage, thicker waterproofing are needed beneath and around the planters and planted areas. Also, leak detection systems may be required to provide early warning before the seepage becomes extensive. Thicker material will add weight to the load but also prevent damage that could be caused by the growth of roots in the long term.
Notwithstanding the nutrients and fertilisers required by the various species of plants to flourish, we also need to consider plant medication to eradicate weeds and to prevent fungus infestations. Would the chemical components from the nutrients, fertilisers and medication lead to corrosion and degradation of walls, timber decks or flooring surfaces? Would the painted areas or concrete surfaces be stained and become an eyesore?
The advantages and positive aspects of sky gardens are well described and documented. The Hanging Gardens of Babylons was often cited as an Utopian vision for sky gardens. However, there is little concrete evidence and details around this ancient Wonder of the World, especially around its irrigation and maintenance.
In present day Singapore, vertical greening is supposed to bring about a better skyline, with splashes of green visually breaking up the solid concrete shapes. Under Singapore’s twelve-month long summer heat, vertical greens also cool down buildings and lower electricity bills for building owners.
Accessibility for regular upkeep and pruning of plants is challenging and costly.
The plants also aid to clear up air pollutants, enrich the oxygen content and improve the general sense of well-being for occupants.
However, within the last few years, we have ample evidence that planters within strata-titled apartments are of limited use as most tenants are not keen on planting and opt to use the planters for non-approved uses (such as extended balconies). Some developers might have abused the GFA-exemption scheme to create inaccessible planters within apartments in order to sell more floor area. Therefore the URA has revised the guidelines to allow for GFA exemption for planters only within non-residential and communal areas of residential projects. According to the URA, “communal skyrise greenery in particular has been shown to be more effective in achieving greenery for the city.” (URA Circular No: URA/PB/2008/17-DCD, dated 7 July 2008.)
However, upfront investment costs and long-term operating costs for these buildings will be increased. Upfront investment costs include the plants, the water supply and drainage, accessories for maintenance such as ladders and safety railings. Operating costs include fumigation, irrigation, cleaning, regular pruning, prevention of potential health issues such as dengue, etc. The question is, even as the savings from lower energy bills outweigh the additional operating costs, are the savings sufficiently large to fully recover the upfront investment costs within five to ten years? If the Returns on Investment are poor, would developers be discouraged from installing these green features in their new builds?
If developers and property owners could treat the upfront costs of installing green features as investments that contribute positively to our environment, then we are heading in the right direction. For most developers and property owners, incorporating sky gardens and other green features count towards their corporate social responsibility (CSR). And in addition, getting a Green Mark Award from BCA or the Skyrise Greenery Award from NParks for a building increases its marketability to prospective investors and tenants. One multi-award winning building in CBD bagged a global MNC tenant after an extensive renovation to incorporate green features into the building.
NParks recently launched a new certification LEAF (Landscape Excellence Assessment Framework) that recognises the provision and management of greenery by architects, landscape architects, developers and maintenance agents. (Source: www.nparks.gov.sg/leaf)
I applaud the move to recognise maintenance agents in the new certification programme. In fact, the vertical greening of Singapore should only be considered a success if the long-term maintenance (say five or ten years after the building is completed) is properly conducted.
Many of the projects that received the Green Mark certification were assessed based on design, and the provisional stamps of approval were given even before construction has begun. The final assessment and confirmation of the Green Mark are given after the projects have received TOP. However, we do not monitor what follows years after TOP. Without long-term commitment of funds for maintenance, these Green Mark certified projects may not be eco-friendly and green as inaccessible planters and landscaped areas may deteriorate and rot. (Note: Green Mark certification would have expired after three years and building owners or Management Committee need to apply for re-certification if they wish for their buildings to remain Green Mark certified).
Perhaps stronger weightage should be given to designs that incorporate features for easy maintenance. During Green Mark assessment checks, developers, architects and landscape designers should be pressed to demonstrate that their designs have adequate provisions for maintenance and servicing of the greenery. All areas with greenery should be accessible (eg. creepers that may grow out of reach?) through staircases and ladders with sufficient safety features for workers in future.
It is my observation that green roofs, sky gardens, highrise planters and vertical walls in buildings with single ownership, in public buildings and institutions and in HDB’s projects, etc. are generally well maintained.
However I am still undecided about the success of vertical greening in strata-titled buildings. A notable exceptional example exists in Newton Suites, a strata-titled condominium block of 118 apartments that was completed six years ago. Unfortunately such examples are rare and what we commonly see are exemplified by Figures 2 and 3. I would rather opt for hard solid facades without planters than to have poorly maintained vertical greenery that subtracts from our vision of being a ‘City in a Garden’.