Policy 4.3 Mixed use development and offices
a Within the Central Activities Zone and the north of the Isle of Dogs Opportunity Area (see Chapter 2 and Annex 1), increases in office floorspace, or those above a justified local threshold, should provide for a mix of uses including housing, unless such a mix would demonstrably conflict with other policies in this plan
b elsewhere in London, mixed use development and redevelopment should support consolidation and enhancements to the quality of the remaining office stock in the types of strategically specified locations identified in paragraph 4.12.
B LDFs should:
a develop policies and strategies taking into account the above spatial principles
b develop local approaches to mixed use development and office provision taking into account the contribution that ‘land use swaps’, ‘housing credits’ and off-site contributions can make, especially to sustain strategically important clusters of commercial activities such as those in the City of London and the north of the Isle of Dogs Opportunity Area. In outer London, the consolidation of surplus office provision can provide opportunities to ‘swap’ new office provision to the most viable types of location outlined in paragraph 4.12.
c where justified by local and strategic office demand and supply assessments and in areas identified in the LDF as having a particular need for local office provision, provide protection for small scale offices (under 500sqm or a justified local threshold) within the CAZ.
d where justified by local and strategic office demand assessments and in areas identified in LDFs as having a particular need for local office provision, require residential proposals within the CAZ which would otherwise result in the loss of office space to make a proportionate contribution to provision of new office space within, or nearby, the development.
4.15 The Mayor encourages mixed use development, with different approaches for places where high office values will generally support other uses, and those where values for other uses (such as residential) may be higher and support some office space renewal. London’s economic growth depends heavily on an efficient labour market and this in turn requires adequate housing provision to sustain it. This can be partly addressed through mixed use development, to deliver a mix of uses across an area, including, but not necessarily exclusively, in mixed use buildings (see also Chapter 3). The concepts of land use ‘swaps’ and ‘credits’ (see Glossary) can support this process as part of local approaches to implementation of this policy in differing circumstances and may be co-ordinated for application across borough boundaries to support the broader objectives of this Plan.
4.16 Beyond CAZ and the north of the Isle of Dogs, mixed use redevelopment can play a role in promoting selective renewal and modernisation of the stock in appropriate locations (see paragraph 4.12) and delivery of other uses including housing as part of a managed process to consolidate the strengths of the office market. Supplementary guidance is provided on this process.
4.17 Within the Central Activities Zone and the north of the Isle of Dogs Opportunity Area, strategically important office development should include other uses, including housing. As a general principle, housing and other uses should be required on-site or nearby to create mixed use neighbourhoods. Exceptions to this should only be permitted where mixed uses might compromise broader objectives, such as sustaining important clusters of business activity, for example in much of the City and the north of the Isle of Dogs, or where greater housing provision, especially of affordable family housing, can be secured beyond this area. In such circumstances, contributions to off-site housing provision should be required as part of a planning agreement.
4.17A In the Central Activities Zone, the differential in office and residential land values has led to concern over the loss of office space to housing even though the area is exempt from government’s liberalisation of Permitted Development rights. Though the development pipeline is sufficient to support demand for new provision, sustained loss of generally more affordable existing stock could erode the Zone’s strategic offer as a competitive, nationally important office location. The Mayor and boroughs will monitor these changes carefully across CAZ. In light of this monitoring and where justified by local and strategic office need assessments, Boroughs should consider raising local thresholds for application of mixed use Policy 4.3 to a level which will actively encourage office renewal but still contribute to housing provision. There is particular concern over the loss of smaller scale offices which are usually part of vibrant, mixed use localities. The Mayor supports boroughs in sustaining office capacity in these areas providing such action can be justified by strategic and local assessments of office need. Further guidance on implementation of this policy will be provided in the Central Activities Zone SPG.
 Mayor of London. Housing SPG. GLA, 2012. Mayor of London. Town Centres SPG. GLA 2014