Density in DesignPaul Sheppard – Taylor Young

RTPI Urban Design Network Regional Quality & Density Debates

Liverpool 23 March 2010

What do we mean by density?

• Dwellings per hectare?

• Beds per hectare?

• Habitable rooms per hectare?

• Intensity of development?

• Types and size of dwelling?

• Footprint of development relative to site?

• Ratio of built form to open space?

• Building heights?

What do we mean by density?

Planning Policy Statement 3: Housing – The statutory definition

Definition: Net dwelling density

Net dwelling density is calculated by including only those site areas which will be developed for housing and directly associated uses, including access roads within the site, private garden space, car parking areas, incidental open space and landscaping and children’s play areas, where these are provided.

Paragraph 49

Careful attention to design is particularly important where the chosen local strategy involves intensification of the existing urban fabric. More intensive development is not always appropriate. However, when well designed and built in the right location, it can enhance the character and quality of an area.

National Policy

What do we mean by density?

By Design: Urban Design in the Planning System - Towards Better Practice

Better Places to Live by Design: A Companion Guide to PPG3

Density and Mix the amount of development on a given piece of land and the range of uses. Density influences the intensity of development, and, in combination with the mix of uses, can affect a place’s vitality and viability.

The density of a development can be expressed in a number of ways. This could be in terms of plot ratio (particularly for commercial developments), number of dwellings, or the number of habitable rooms (for residential developments).

National Best Practice

Grange View, Henlow

27 dph 31 dph

Bishops Stortford

34dph

Poundbury Phase 1

What does “X”dph look like today?

What does “X”dph look like today?

Cala Domus – New Hall

38dph 45 dph

Upton – Phase 1Didsbury Point, Manchester

42 dph

What does “X”dph look like today?

Rolls Crescent, Hulme

54dph 102 dph

Deansgate Quay, ManchesterGreenland Passage, Southwark

68 dph

But what can go wrong?

• Overlooking issues

• Poor permeability

• Overcrowding

• Traffic problems

• Poor management

• Lack of open space

• Parking issues

• Fear of crime

• Isolation

• Poor public transport provision

• Provision of local facilities

• Inappropriate housing mix & tenure

• Lack of activity

• Development with too low a density for the context

• Development with too high a density for the context

Inappropriate density can cause…

Can good design address all these issues?

• Focus on activity centres & transport hubs

• Vary the density profile

• Urban density should not been town cramming

• Cater for the right life styles

• Blend the best parts of town

• The intensity pyramid

• Informed by the context

What should we be doing?

What should we be doing?

Current issues

Developers:

– Setting the agenda in the current market

– Want to maximise the return on houses that they think they can sell

– This can cause a blunt response to market with…

Current issues

• Polarised development of:

1. Detached 3 / 4 bedroom houses with on plot parking and gardens

2. Crammed 2 bedroom micro-houses with parking courts and scraps of gardens built as the alternative to

• Universal resistance to apartments due to oversupply, this leads to:

– Difficulty in turning corners

– Difficulty in providing appropriate height and scale

– Intensive development over-localised in town and city centres

Current issues

The result is a continuing failure to

– Adequately address the context

– Apply good design principles

The challenges ahead

• A design led approach

• Really understanding context

• Practitioners as advocates for good design

• Bringing ambitions of LPA / developer together

• Delivering quality places, not target densities

• Avoiding fixation of density in isolation