Parkmount Housing
By Richard Partington
Summary of our design ideas through the case study of Parkmount housing, completed in 2003
In our work we try to make connections between good design and 'placemaking', between daylighting and the quality of internal spaces and between responsible energy use and healthy living. This journal entry offers a summary of some of these ideas. It looks at the main themes of solar design, energy, and health and wellbeing and how these affect the decisions we all make when we choose somewhere to live.
Background
In Belfast the tentative steps towards a more peaceful and integrated society have yet to be reflected in the physical landscape, which is still marked by the provocative murals, the painted kerb lines, and the oppressive walls that separate communities.' Everywhere there are constant reminders that Belfast is a patchwork mosaic of neighbourhoods.'
These are the characteristics of the southern end of Shore Road and our site, known as Parkmount. To the south-west is the mainly derelict and notorious Mount Vernon estate, once scheduled for demolition. Immediately to the east is the Shore Crescent estate, a Protestant community planned in the seventies around a series of 'secure' dead-end roads and culs-de-sac, as was the practice for housing layouts of the time. Further to the east again is the new motorway, which runs parallel to Shore Road along the edge of Belfast Lough.
Brief
In 1997 The Northern Ireland Housing Executive, the main public body responsible for delivering housing, established a project team to promote new ideas in housing design with the intention of building these into a demonstration project. The NIHE then looked to private developers, through a tender process, to deliver the project and take the risk for marketing and sales. There was a process of negotiation and discussion with the winning tenderer, the Carvill Group, that clarified at the outset the aims of all the parties and set down the benchmarks for assessing the environmental performance of the scheme.
The accommodation consists of fifty-six two-bedroom apartments (approximately 60sqm) with two smaller one-bedroom apartments, giving a density of 97 units per hectare (290 habitable rooms per hectare). Forty-six of the apartments have wheelchair access and internal dimensions that suit wheelchair manoeuvrability.
The key components of the brief are:
Flexible apartment plans to anticipate changes in work patterns and lifestyles
Creation of a defined 'place' with landscaping and safe play area
A completely secure development with controlled access
A logical sequence for marketing and constructing the scheme in phased stages to limit the financial risk
Simple and reliable technical solutions that will be economic to run and maintain
Attainment of the BRE EcoHomes Standard
Good design for maximising solar potential with a high research and innovation component centred around the use of PVs
Regeneration
Together with urban designers Llewelyn Davies, we proposed the concept of a 'linear community' for Shore Road with shops, health, leisure and employment along with an intensification of the public transport corridor.4 We wanted the scheme to become a sort of beacon, to register sufficient presence and scale on the derelict landscape and to represent the new optimism and ambition of the City. We hope that on a clear day it might even be visible from the more affluent areas on the south-eastern side of the Lough.
We made a wider study of the area for which several strategic plans were produced. These plans proposed a better use of the existing infrastructure. We suggested a commuter stop to the railway on the other side of the road from the Parkmount project. Multiple crossing points could then be provided to give access from both sides of the road and introduce some much-needed traffic calming. New pedestrian footpaths could stimulate improvements to frontages and the public domain and make connections through the dead-end cul-de-sac layout of Shore Crescent. The commuter stop was imagined as one of a series of positive interventions, including new changing facilities for the playing fields, a sports hall and clinic or surgery. Each of these would be coupled with existing buildings or uses to concentrate activity and make efficient use of resources.
Urban design
On the housing site itself we tried to present a positive edge to the public domain – a proper street frontage. We thought that the scale of the development should relate to the scale and importance of the road itself rather than the two storey fragments around the site. Urban issues were considered alongside the main ambition to achieve an exemplary energy performance. To do this we had to realise the maximum 'solar potential' of the site, considering both daylighting, passive solar gain and the use of photovoltaics. We also aimed to create a high-quality landscaped space that would be central to the whole project. This space had to be useable i.e. overlooked, secure, well lit, sheltered and densely planted. The planting was essential to improve the ecology of the site and to structure the courtyard space and screen the residents' parking.
Site layout
One of the perceived shortcomings of post-war housing design is the failure to address the issues of ownership and demarcation of space. Landscape areas and open space whose ownership is common or ambiguous is often poorly maintained or vandalised, which in turn has implications for crime prevention and personal security. However, in Belfast this is not just a question of providing natural surveillance and distinguishing 'front and back' or 'public and private'. Understandably, house purchasers expect high levels of visible security and active surveillance and gated developments with security cameras are not uncommon. We were uncomfortable with the idea that Parkmount might be conceived as a secure 'enclave' – this seemed to contradict the notions of permeability and pedestrian movement that underpin regeneration planning.
Security
At Parkmount a number of devices are used to establish clear but secure entrances to the project and to delineate the transition from street pavement to dwelling entrance. In Victorian and Edwardian housing this transition would have been marked by a series of thresholds each reinforcing the demarcation of private ownership: the gateway, front garden, the steps up to the front door, portico or porch, etc. At Parkmount, the single shared space has one secure access point, so it is not a public space, but gaps between the buildings are placed to give glimpsed views into the courtyard and these are emphasised on the street edge where there are breaks in the low wall and railings. At these points paired free-standing brick pillars with small canopies and lighting suggest gateways and entrances. In the future, with the emergence of a safer and less troubled society, it will be possible to connect these gateways directly to the landscaped court with footpaths.
Solar design
The roof profile is the distinguishing feature of the project. It helps to unify the whole scheme so that each of the repeated blocks is seen as part of a considered whole. The strength and clarity of the roof form is also a clear architectural representation of the central theme of solar design, which has influenced every aspect of the project.
Through a series of massing and site studies we examined the possible forms for the roof-scape and checked there would be no overshadowing. The aim was to maximise the surface area that could present an optimal inclination and orientation to the southern sky (within plus or minus 20° of due south). The form of the buildings responds directly to the 'solar logic' with the lowest roof at the southern end of the site ascending at a constant 5° angle towards the north and culminating in the nine-storey tower. The development of the arrangement and massing of the buildings is discussed in a case study in the book ‘Photovoltaics and Architecture’.
Even though the living spaces have various orientations more than eighty percent of the apartments will have good sunlight penetration and many have dual aspect living rooms that are ideal for a normal working day, giving direct sunlight in the morning and the evening. Those apartments in the tower that do not have an ideal solar orientation, because of the density and the constrained site, have the compensation of the best views in a north-east direction towards the Lough.
The quality of daylight in interior spaces and the potential for passive solar design seems to be ignored in so much recent housing where small windows are the norm. By paying attention to these issues we believe the quality of the internal spaces and their marketability has been greatly increased.
An array of 70sqm of grid-connected photovoltaic panels was designed with an estimated annual output of 4,400kWh/year, which should provide equivalent electricity to meet the annual consumption of two of the apartments. The design for this sample roof area (fixing, access, cable routing, inverter design, etc.) can be applied to all the low-rise units in the future. The scheme uses amorphous silicon modules, factory-bonded to the single-ply roofing membrane and protected by a fully weatherproofed transparent polymer coating. The amorphous silicon can be applied in very thin, flexible layers, which makes it very suitable for use with lightweight roof membranes. On the other half of the same block an installation of solar thermal panels is also proposed, providing pre-heating of hot water to all of the apartments below. One 2.5 by 1.3m panel, with an effective absorber area of 2.8sqm, will be installed per flat. The cost of the revised heating system and the energy saving for each type is going to be monitored.
Building construction and appearance
The external elevations combine panels of smooth render with textured brickwork. Punched windows in the masonry walls have deep-set window reveals to emphasise their thickness and mass. The additional thickness is a result of the wider than usual cavity, in this case 140mm, to achieve a significant increase in the U-value (30% better than the Building Regulations requirement). The cavity is filled with a polystyrene bead insulation, chosen for its environmental performance, having a zero-ozone depletion value. The base of each building is emphasised with a full storey height of blue engineering bricks.
The corners of the buildings have full height glazed panels with doors onto projecting balconies, each with a finely detailed metal balustrade, in contrast with the mass of the masonry elements. The clean lines of the corners are repeated around the stair cores and entrances where transparent glass is used to suggest openness and arrival. Glazing to the common areas will ensure that distant views can also be enjoyed from the stair cores. The glazing, which also contributes to the high thermal performance, incorporates a low-E glass to achieve an average U-value of 1.9W/m2K. The wall design and the window specification represent the main departures from standard house building practice and raised particular questions on the construction of the tower where the effectiveness of the full filled cavity in protecting the inner leaf from water penetration had to be considered. Structurally. the walls are subject to high wind loads at the upper storeys and the relevant safety factors also had to be built into the design.
Sustainable urban design
A sustainable neighbourhood has to be successful and desirable. Housing designers have inherited a legacy of social experimentation and unsustainable optimism, characterised by failed housing estates and New Town plans. Now planning authorities and planning guidance has retreated towards the opposite extreme of conservatism and historical sentimentality' but we believe there is a demand for a humane modern aesthetic.
While designing Parkmount our team has been considering diverse and seemingly unrelated issues – the question of security and how it will have an effect on the desirability of the area and the scheme, alongside the possibility of using photovoltaic technology, a technical field that is still in its infancy. In both cases we have tried to look forward; in the case of security, to a time when the scheme may become more permeable and accessible and less inclusive. The buildings have been designed to sustain the changes that may arise from this culture shift. In the case of solar design, we have made the roof planes and surfaces so that they will provide the optimum orientation tor solar panels, anticipating a day when their pay back period and the universality of their construction techniques makes them suitable for every new building and refurbishment project.
We have done our best to realise the environmental potential of our site, but without compromising a broader understanding of the public realm - Belfast City, its location; its heritage; the typology and forms of its buildings and streets; and the richness and diversity of its culture.
