The new NPPF provides backing for upward extensions.
This is designed to make use of the airspace above existing buildings where there is scope to extend them. An earlier consultation on this proposal for London contemplated the possibility of permitted development rights or local development orders but the preferred approach was identified as planning policies to support this type of development and it has been crystallised in the NPPF.
This change to the NPPF is therefore not a permitted development right and should not be seen as an automatic yes. It does however give support in principle to extensions above existing residential and commercial premises for new homes. This is something that could be applied for anyway so it does not introduce a new concept, but it does confirm that such proposals for new homes should be supported as long as the extension would not reach beyond the adjoining roof lines and would be in keeping with the overall street scene and are well designed and safe access can be achieved.
This approach is likely to be welcomed by the industry in principle as it supports the type of innovative approach that is required to find space for additional housing in highly developed areas. There will however be complications with these proposals with the most obvious one being viability. Some sites will undoubtedly be more complicated than others and this could lead to viability issues.
How local authorities will treat these sites with regard to CIL and planning obligations will undoubtedly therefore have an impact on their deliverability. As with the other policies promoting higher density development, the impact of this type of development on existing infrastructure will need to be considered carefully to ensure that acceptable developments can take place.