Fitting In
New Design in Urban Conservation Areas
Emma Lawrence
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| A splash of modernism in the heart of Bath: Grimshaw's Thermae Bath Spa (Photo: Thermae Bath Spa) |
Conservation areas are places in villages, towns and cities which are designated by local authorities for the contribution they make to our built environment. What makes them special is their unique combination of buildings, streets and spaces which contribute to a strong sense of place. In urban conservation areas, change is inevitable as our urban historic townscapes are dynamic places that are constantly adapting to the needs of their inhabitants. When that change comes, good quality new design in these areas can enhance what’s already there and reacquaint us with the area’s unique importance and idiosyncrasies.
2017 marked the 50th anniversary of the 1967 Civic Amenities Act which first introduced the concept of conservation areas. Half a century on, there are now 513 designated conservation areas in Wales, over 600 in Scotland, and 10,100 in England which in total cover an area the size of Luxembourg. Conservation areas are often comprised of a mixture of locally important buildings, designed or natural landscapes, local and regional materials and types of construction, and historic street patterns and elements which reflect the local culture and tradition. The way in which all of these elements interact and relate is unique to each area and is often referred to as local distinctiveness, and this is what must be preserved throughout the planning process. Not only are the areas important for their local distinctiveness, they are places which likely include nationally important heritage assets. For example, of the 10,100 conservation areas counted in England in 2017, 93 per cent contain listed buildings, 19 per cent include a scheduled ancient monument and 10 per cent include all or part of a registered park or garden. In planning and heritage protection terms, conservation areas are incredibly complex places.
In recognition of their complexity and importance, conservation area status introduces stricter planning controls which acknowledge that the accumulation of seemingly innocuous small alterations and more obviously, new development, can harm the special character of a conservation area. Just as those planning controls allow planning officers to require homeowners in conservation areas to use high-quality materials for new features (such as windows), they also require developers to put forward high-quality designs for new buildings in conservation areas. Where these controls are improperly enforced, conservation areas can be quickly devalued through negative change, damage and neglect, and become at risk. To combat this, there are powers in place that allow local authorities to help prevent neglect and damage, but arguably good new design is one of our greatest tools to ensure that the special character and appearance of conservation areas is protected.
Urban conservation areas are currently experiencing a rate of change which could see many of them irreparably altered. The reasons for the high rate of change are manifold but ultimately the presumption in favour of sustainable development by governments is the driver. Each of the four home nations has some form of national planning framework and across them all the push for sustainable development is the overarching common principle. Sustainable development is defined in the Brundtland Report as the process of improving the economic, social and environmental well-being of the country to meet the needs of the present, without compromising the ability of future generations to meet their own needs. Just because an area is historic or has a character or appearance that makes it special, it doesn’t mean it is exempt from this presumption for new development. To take England as an example, to meet the current needs for housing and new development, the National Planning Policy Framework 2018 directs local planning authorities to look for opportunities for new development within conservation areas.
Not all conservation areas are no-gos for development. Many of our urban areas, and by extension many of our conservation areas, have been blighted by poorly designed buildings and developments that detract from the character of places by creating gaps or monoliths in the topography of our streetscapes, negatively impacting the way we experience them. Today, arguably, those sites represent opportunities for redevelopment and perhaps larger urban regeneration projects. In order not to repeat the mistakes of the past we must approach those sites with a set of principles which aim to improve that area, and in the case of sites within conservation areas, new development must also preserve the areas’ unique importance.
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| Located within the Maritime Greenwich World Heritage Site, the proposed design for the Stockwell Street Library at Greenwich University was considered insufficiently traditional by UNESCO's World Heritage Committee. The design was adapted and a fine grain approach was adopted, reflecting the scale and massing of its urban surroundings. (Photo: Hufton & Crowe for Heneghan Peng Architects |
In order to preserve and improve an urban conservation area through new development, both its historic importance and its communal value and functionality must be assessed and understood. Pinpointing the significance of a conservation area is a difficult task, but to get a clear picture of an area’s importance the assessment of it should explore the relative value of the elements and buildings which make up the area, and the sequence of change to the area over time. Once the importance of the conservation area and the buildings within it have been understood, this knowledge should underpin and inform the design of a new development.
To improve an area, designers must assess the strengths and weaknesses of the way an area functions. Successful streets, towns and cities have characteristics in common and these factors have been used to form the objectives of urban design. Broadly, those objectives are: that new development should seek to create a place with its own identity; that private and public spaces are distinguishable from each other and open spaces are successful; that a place that is easy to understand and adaptable, and where amenity is diverse. These objectives take into account the fact that whether or not we can articulate why badly designed areas and buildings don’t work, we will have a negative experience of those places. For this reason, not only does good new design come from understanding a place, which is crucial to protecting the historic and aesthetic importance of conservation areas, it also has the value of enlivening it and having a real impact on the way a community feels about its area.
Good design results from consideration being given to a broad range of concerns relating to the form of new buildings, structures and spaces. Form is the physical expression of urban design and the following considerations will influence a new building’s form.
PROPORTION, SCALE AND HIERARCHY
In order to respond well to its context, a new development should consider and complement the prevailing townscape of a conservation area. This includes taking account of and responding to distinctive local building forms and the historic pattern of development in the area.
The relationship between the height of buildings and the streets they flank and enclose is of critical importance to maintaining the character of urban conservation areas. A common characteristic of successful new design in urban conservation areas is its attention to human scale. Developments which are overbearing and starve the street of light and air can have a substantially detrimental impact on urban streetscapes because we feel uncomfortable and overwhelmed within them. As a general rule the scale of a new building should relate to the width of the street it occupies.
Another general principle to consider is that new buildings should respect the height of the surrounding area. This does not necessarily mean that all new buildings in conservation areas should be smaller in scale to the existing buildings: subservience isn’t always the correct design approach. For example, some urban townscapes may benefit from a landmark building on a vacant site that takes its cue from the surrounding area and stitches it back together. The appropriateness of this approach will depend on the hierarchy of the existing buildings and their massing and proportions, although there is generally more scope for change to heights and rooflines in streets where there is a variety of building heights and frontages. In the case of conservation areas which are designated for the uniformity of design of the buildings within them, a new building that was out of scale with the original design intention would likely be inappropriate.
RHYTHM AND URBAN GRAIN
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| Designed by the architects Roger Stirk Harbour + Partners, the World Conservation and Exhibitions Centre attached to the Bristish Museum maintains its own identity, yet it remains sympathetic to the exisiting architecture of both the Bloomsbury conservation area and the museum itself. (Photo: Roger Stirk Harbour + Partners) |
The rhythm of a street is defined by building heights, massing and the way in which façades are articulated. It is possible for the accretion of buildings from different periods in our urban conservation areas to either contribute to or disrupt the rhythm of streetscapes. In order not to be disruptive, new buildings which are skilfully woven into their context and respect the scale and rhythm of the existing street frontages are likely to be the most successful from a design perspective.
To create harmonious conservation areas, the elevational treatment of new buildings is of crucial importance. It determines the way in which a new building will relate to its neighbours and the public realm as well as communicating its use and architectural intent. Urban conservation areas are likely to be characterised by a vertical emphasis where plots are narrow and the height of a building or streetscape is greater than the width of the building(s). This is known as fine grain. Where the plots in a conservation area are large and infrequent this is known as coarse grain.
Verticality is expressed not only in a building’s dimensions, but also in individual elements such as fenestration, the roofline, and the treatment of the ground floor of buildings. Given the pressure for the optimal use of sites to provide the most accommodation, larger or longer street frontages may be necessary. In order to maintain a fine urban grain, vertical articulation and proportions can be used to ensure that the new, bulkier building relates to the rhythm of the street, as well as adding interest to the conservation area.
COMPLEMENTING OR CONTRASTING DESIGNS
Successful architecture can be produced either by closely following historic precedents in a conservation area, or by adapting them or even contrasting with them. Local building forms and details contribute to local distinctiveness, however, this does not mean they must be followed and replicated in a pastiche way. Indeed, in a diverse context a contemporary building may be less visually intrusive than one making a failed attempt to follow the area’s historic precedent. Rather, good new design should seek to incorporate those details and forms into a new development in a way that is innovative but not shouty. In urban areas particularly, new design can become competitive, with new buildings vying for awards and photogenic ‘after’ photos. Usually this is dependent on the new contrasting with the old, but this is only ever successful where the new also complements it. A new building with ambitions of contrasting with an historic area in a way that is sympathetic to it requires considerable thought and execution in its detailing and materiality.
Creating a modern and contrasting design is one example of a successful approach, but it should not overshadow the more quiet approach of a design which complements and embraces the historic area or building, without looking to announce itself as the new arrival.
MATERIALITY
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| Pollard Thomas Edwards' extension to the Granary, a listed 19th-century building in Barking and Dagenham, acknowledges the scale and rhythm of the original building while adopting a contemporary approach to the form and detail. (Photo: Pollard Thomas Edwards Architects) |
Materiality is linked to the ideas about complementing and contrasting design. Employing the prevailing material palette of surrounding buildings in a conservation area will settle a new building into its context, giving it the same qualities of the existing buildings. On the other hand using a different, but sympathetic material palette will put a new building in contrast with the area.
Beyond making clear the building’s overall design intention, the richness of a building lies in its use of materials. The key materials that provide buildings with the means to transcend an off the peg appearance are stone, timber, clay, metal and glass. Traditional, natural and handmade materials provide richness and texture which modern materials, by and large, fail to deliver. Additionally, organic and traditional materials have proven to be durable, and to weather in a way that is pleasing. The rate and relative ageing process of different materials should be an important consideration when specifying them for a new building. Stone, timber, copper and lead all accumulate a pleasing patina as they age which both softens them and makes them more dynamic. Longevity and durability are an area where modern materials fall down, often looking worn and poorly maintained rather than nicely aged.
The value of conservation-led new design, regeneration and adaptive reuse of buildings in urban conservation areas has been proven to work. Despite this and the crucial social and environmental importance of the historic environment, heritage has been largely absent in the broader sustainable development debate. To those of us already working to protect the historic environment, its value is clear; historic areas and places act as an enabler and a driver to development, and projects defined by good design have the potential to be hugely socially rewarding. Through our own work and in discussion we must continue to advocate that integrating a concern for heritage protection and good new design in historic contexts into all areas of planning and design fundamentally contributes to sustainable and richer communities.
FURTHER INFORMATION, LEGISLATION AND GUIDANCE
C Mynors, Listed Buildings and Other Heritage Assets (5th edition), Sweet & Maxwell, London, 2017
England
Planning (Listed Buildings and Conservation Areas) Act 1990
The National Planning Policy Framework
Planning Practice Guidance; Conserving and Enhancing the Historic Environment
Northern Ireland
Planning Act (Northern Ireland) 2011
The Planning (Listed Buildings) Regulations (Northern Ireland) 2015
The Strategic Planning Policy Statement (SPPS) (2015)
Planning Policy Statement 6 (PPS6): Planning, Archaeology and the Built Heritage (1999)
Scotland
Planning (Listed Buildings and Conservation Areas) (Scotland) Act 1997
Historic Environment Scotland Act 2014
Planning (Listed Building Consent and Conservation Area Consent Procedure) (Scotland) Regulations 2015
Historic Environment Scotland Policy Statement (2016)
Historic Environment Circular 1
Guidance notes in the Managing Change in the Historic Environment series
Wales
Planning (Listed Buildings and Conservation Areas) Act 1990
The Historic Environment (Wales) Act 2016 and associated regulations
Planning Policy Wales
Government Circulars 61/96, 60/96 and 1/98 Technical Advice Notes
