15.5 - Site Characteristics and Design Parameters

The following section provides guidance on identifying the high level characteristics which shape the urban design response to a site to ensure the creation of good quality urban environments. Development proposals should make the most efficient use of land by delivering an optimum density and scale of development for the site having regard to its location within the city.

Certain areas of the city, such as those located adjacent to high quality public transport will lend themselves to a more intensive form of development. Similarly, brownfield and infill sites can also achieve greater densities subject to the location and proximity to other services. Appendix 3 of the plan sets out guidance regarding density and building height in the city in order to achieve sustainable compact growth.

In considering the appropriateness of a development at a city scale, applicants should demonstrate that the scheme proposed has adopted an appropriate approach to urban intensification broadly consistent with its location.

The key design parameters shall be addressed as part of an Architectural Design Statement to accompany development proposals. Applicants are encouraged to utilise early iterations of the design statement in pre planning consultations with the Planning authority.

15.5.1 Brownfield, Regeneration Sites and Large Scale Development

This section refers to the development of brownfield, regeneration and large comprehensive sites which are of sufficient scale to differentiate them from the surrounding townscape.

Brownfield sites are generally referred to as previously developed lands that are not currently in use. Quite often these brownfield sites are located in areas in need of regeneration. These sites often contain derelict or vacant buildings which are underutilised and in need of redevelopment. Brownfield lands have the ability to regenerate and rejuvenate large portions of the city through redevelopment.

Dublin City Council will seek to ensure the following considerations are incorporated in proposals for large-scale, regeneration and brownfield development:

• To encourage innovative, high quality urban design and architectural detail in all new development proposals.
• To analyse and review the surrounding built environment to ensure the new development is consistent with the character of the area.
• To respect and enhance existing natural features of interest.
• To contribute to the streetscape creating active and vibrant public realm.
• To create animation and create activity at street level and vertically throughout the building.
• To provide for appropriate materials and finishes in the context of the surrounding buildings.
• To ensure land contamination is appropriately dealt with and mitigated against.
• To provide high-quality new streets and open spaces connecting into the surrounding street pattern/ open space network.
• To create new compositions and points of interest.
• To provide an appropriate mix of uses comprising retail, residential, recreational, cultural, community- and/or employment generating uses to improve the existing range of uses and facilities in the area.
• To carefully integrate appropriate landscape planting and trees and retain and ecological features on the site.
• To prioritise pedestrian and cycle movements in connection with public transport infrastructure.
• To retain existing and create new features to make an easily navigational urban environment, including active building frontages with clearly defined edges and safe public routes.
• To build in capacity to incorporate services to meet changing demands including pipe subways and infrastructure to allow future connection to district energy networks.
• Ensure waste management facilities, servicing and parking are sited and designed sensitively to minimise their visual impact and avoid any adverse impacts on users of highways in the surrounding neighbourhood.

15.5.2 Infill Development

Infill development refers to lands between or to the rear of existing buildings capable of being redeveloped i.e. gap sites within existing areas of established urban form. Infill sites are an integral part of the city’s development due to the historic layout of streets and buildings.

Infill development should complement the existing streetscape, providing for a new urban design quality to the area. It is particularly important that proposed infill development respects and enhances its context and is well integrated with its surroundings, ensuring a more coherent cityscape.

As such Dublin City Council will require infill development:

• To respect and complement the prevailing scale, mass and architectural design in the surrounding townscape.
• To demonstrate a positive response to the existing context, including characteristic building plot widths, architectural form and the materials and detailing of existing buildings, where these contribute positively to the character and appearance of the area.
• Within terraces or groups of buildings of unified design and significant quality, infill development will positively interpret the existing design and architectural features where these make a positive contribution to the area.
• In areas of low quality, varied townscape, infill development will have sufficient independence of form and design to create new compositions and points of interest.
• Ensure waste management facilities, servicing and parking are sited and designed sensitively to minimise their visual impact and avoid any adverse impacts in the surrounding neighbourhood.

15.5.3 Alterations, Extensions and Retrofitting of Existing Non – Domestic Buildings

In Dublin city centre, the form and grain of the built environment leads to substantial pressure for extensions and alterations to existing buildings. Works of alteration and extension should be integrated with the surrounding area, ensuring that the quality of the townscape character of buildings and areas is retained and enhanced and environmental performance and accessibility of the existing building stock improved.

The retrofitting of sustainability measures to existing buildings, and extensions and adoption to new uses is of crucial importance, as this will always represent a much greater proportion of the building stock than new buildings. Retrofitting seeks to ensure that all new development considers how environmental performance can be improved; this may include measures to reduce energy consumption and improve efficiency and incorporate renewable technologies as well as improving water efficiency and minimising waste, wherever possible.

Dublin City Council will seek to ensure that alterations and extensions will be sensitively designed and detailed to respect the character of the existing building, its context and the amenity of adjoining occupiers. In particular, alterations and extensions should:

• Respect any existing uniformity of the street, together with significant patterns, rhythms or groupings of buildings.
• Not result in the loss of, obscure, or otherwise detract from, architectural features which contribute to the quality of the existing building.
• Retain characteristic townscape spaces or gaps between buildings.
• Not involve the infilling, enclosure or harmful alteration of front lightwells.
• Incorporate a high standard of thermal performance and appropriate sustainable design features.

In addition to the above, alterations and extensions at roof level, including roof terraces and set back floors, are to respect the scale, elevational proportions and architectural form of the building. Key considerations include:

• New development will respect terraces or groups of buildings with a consistent roofline.
• Development will not result in the loss of roof forms, roof coverings or roof features (such as chimney stacks) where these are of historic interest or contribute to local character and distinctiveness.
• Green roofs should be incorporated wherever they accord with the above, are structurally viable and have no adverse impact on historic structures – see Appendix 11.
• Minor external additions to buildings such as plant, telecommunications and other equipment and associated cables and fixings shall be concealed within the building envelope where feasible or designed and sited to minimise their visual impact. All redundant equipment should be removed prior to installation of new equipment.

15.5.4 Height

Appendix 3 identifies the height strategy for the city and the criteria in which all higher buildings should be assessed.

15.5.5 Density

Dublin City Council will support higher density development in appropriate urban locations in accordance with the NPF, RSES and the Section 28 guidelines which seek to consolidate development within exiting urban areas. Higher density development allows land to be used more efficiently, assists in regeneration and minimises urban expansion. Higher densities maintain the vitality and viability of local services and provide for the critical mass for successful functionality of public transport facilities.

New development should achieve a density that is appropriate to the site conditions and surrounding neighbourhood. The density of a proposal should respect the existing character, context and urban form of an area and seek to protect existing and future amenity. An urban design and quality-led approach to creating urban densities will be promoted, where the focus will be on creating sustainable urban villages and neighbourhoods.

All proposals for higher densities must demonstrate how the proposal contributes to place-making and the identity of an area, as well as the provision of community facilities and/or social infrastructure to facilitate the creation of sustainable neighbourhoods. Refer to Appendix 3 for further details.

15.5.6 Plot Ratio and Site Coverage

See Appendix 3 for further detail.

15.5.7 Materials and Finishes

The materials and finishes of a building have the ability to shape the architectural design quality and distinctiveness of an area. Materials and finishes should be selected to ensure longevity throughout the lifetime of the development. All developments will be required to include details on the maintenance and management of the materials proposed as part of the planning application. As such, Dublin City Council will require developments:

• To ensure materials and finishes complement the existing pallet of materials in the surrounding area.
• Promote durability to ensure a good visual appearance over time.
• The design and layout of buildings, together with the robustness of materials used in their construction, should be such as to discourage graffiti, vandalism and other forms of anti-social activity.
• To support the use of structural materials that have low to zero embodied energy and CO2 emissions as well as the use of sustainably sourced building materials and the reuse of demolition and excavated materials.

15.5.8 Architectural Design Statements

Applications for 50+ residential units should be accompanied by an Architectural Design Statement or any application below the threshold where the planning authority consider it necessary. Statements may also be required for large scale commercial development. An Architectural Design Statement is an informative, illustrative document that clearly describes the development proposal, the context in which the development is set and the design rationale for the scheme. Design statements should analyse the site context, planning context, opportunities and constraints of the site and the conceptual and detailed design of the development including the building massing, material and finishes and building articulation, (see also Policy SC23).

Design Statements should include the following information as set out in the table below which build upon the detail of the key design parameters.

Table 15-2:      Information Requirements for Design Statements

15.5.9 Models and Photomontages

In the case of certain large or complex planning proposals, models and photomontages of a proposed scheme to an appropriate scale will be required by the planning authority. All photo-montages submitted with a planning application or Environmental Impact Statement must include details of the type of camera and the lens used to create the image. The development should be clearly depicted. The inclusion of excessive sunshine, blue sky and any other detailing or colouring which may distort the reliability of the photomontages should be avoided.