Establishing and Quantifying the Impact of Planning
Although broad categories of planning regulation and potential cost implications for housing development are readily conceptualised (as given in Table 4.1), it is much more difficult to measure these impacts in a definitive way. In nations characterised by land use zoning and codified development controls, regulations are typically extensive and may vary considerably between otherwise comparable local jurisdictions. For instance, in the USA, thousands of municipalities, cities, counties and towns, have developed their own planning schemes and rules, albeit within legal frameworks set by state governments. This situation has enabled almost infinite variation in local approaches to development control across the major cities of the USA (Pendall et al. 2006; Gyourko et al. 2008). In the UK, although there are fewer local authorities and a national planning framework, the lack of codified regulations means that measuring and comparing local differences in planning approach is equally complex (Bramley 1998, 2014).
Approaches to defining and measuring planning restriction, and estimating its impact, have included:
• Before/after analyses, which follow the introduction of new planning controls or a system change, such as the introduction of zoning (Zhou et al. 2008; McMillen and McDonald 1999), or environmental protections (Chamblee et al. 2009).
- • Spatial land capacity analyses, which estimate development opportunity and constraint based on zone coverage and/or the stock of potentially developable residential land (Hui and Ho 2003; Buxton and Taylor 2011; Bramley 2014) (also Bramley and Watkins 1996 Steering the Housing Market).
- • Rates of development approval/refusal, on the basis that the propensity to approve or refuse housing development is an indication of planning restrictiveness (Hilber and Vermeulen 2009).
- • Efficiency measures, such as the speed and timeliness of planning decisions, which are thought to affect both tangible costs for developers (financial holding costs), as well as certainty and confidence in decision outcomes (Ball 2010).
- • The cost, design and use of development contributions collected for the provision of infrastructure and other community benefits (Evans- Cowley and Lawhon 2003; Crook et al. 2010).
- • Detailed survey-based data on the content of local planning schemes, and in particular restrictiveness relative to plans applying to comparable local areas (Gyourko et al. 2008; Glaeser and Ward 2009; Levine 1999).
- • Proxy measures of local government planning commitment and/or development stance. For instance, levels of local authority expenditure on spatial planning activity has been used as a proxy for commitment to and engagement in, comprehensive planning in Florida (Ihlanfeldt 2009); and the political composition of local government representatives has been used as an indication of likelihood to support new development (Kahn 2011; Bramley 2013, 2014).
Of these potential measures, it is possible to further group research approaches according to the particular planning system impact being examined. We distinguish three broad measures of impact: ‘restrictiveness’ (which could apply to either restrictions on the supply of developable land/planning consents, or controls on the density and mix of housing [such as building type, height, floor space regulations, etc.]); ‘uncertainty and delay’ (administrative considerations regarding the time needed to secure rezoning/planning approval and relative predictability of decisions, and the actual time in which this ‘stock’ of potential housing sites is released relative to the flow of housing completions and infrastructure capacity); and ‘costs’ (particularly direct costs associated with securing planning approval, such as impact fees or development contributions).