Permitted development rights to support the provision of new homes: SEA Environmental Report

7. Conclusions and recommendations

7.1.1 This section provides a summary of areas of the potential environmental effects across the SEA topic areas for all of the development types covered in this report.

7.1.2 Depending on which options are taken forward, extending PDR for the conversion of agricultural and forestry buildings could have significant negative effects on cultural heritage. There is also potential for minor negative effects for biodiversity, landscape and geodiversity, soils and water. There is potential for significant negative effects on population and human health from the conversion of agricultural and forestry buildings where PDR removes the opportunity to consider matters such as environmental harm though the planning process. This is uncertain and dependent on the proximity of any hazardous sites to new development proposals. There is potential for significant negative cumulative effects on water (flood risk) if options to remove existing PDR restrictions on the cumulative number of units created are taken forward alongside options to remove existing PDR footprint limits.

7.1.3 All options to introduce PDR for new homes in rural areas have potential for significant negative effects on cultural heritage though these are uncertain. Depending on which options are taken forward, there is also potential for significant negative effects for biodiversity, landscape and geodiversity, material assets, population and human health, soil and water. All options have potential for minor negative effects on climatic factors.

7.1.4 All options to introduce PDR for town centre living have potential for minor negative effects on water (flood risk). Both options for changes of use have potential to result in minor mixed effects on cultural heritage and introducing PDR for external alterations to facilitate conversion has the potential to result in minor negative effects on cultural heritage from physical alterations to the buildings and where PDR impacts the setting of a historic environment asset. Introducing PDR for external alterations has potential to result in minor negative effects on material assets while introducing PDR for change of use has the potential for minor mixed effects climatic factors and material assets.

7.1.5 Options to allow expanded householder PDR in conservation areas have potential to result in significant negative effects on cultural heritage. Other options have potential for minor negative effects on cultural heritage. Depending on which options are taken forward, there is also potential for minor negative effects on biodiversity, landscape and geodiversity, soils and water. All options have potential minor positive effects on material assets.

7.1.6 All options to extend PDR for domestic air source heat pumps have the potential to result in significant negative effects on cultural heritage where there is an impact to a heritage asset or its setting. All options also have the potential to result in minor positive effects on climatic factors and material assets associated with the uptake of this type of technology.

7.1.7 Introducing PDR for connections to heat networks has potential for minor negative effects on cultural heritage and soils where below ground works impact heritage assets or valuable soil resources. It has potential to result in minor positive effects on climatic factors and material assets associated with the uptake of this type of technology.

7.1.8 Within and across development types, options for PDR together may result in significant negative cumulative effects on biodiversity, flora and fauna. Key potential contributors include the conversion of agricultural and forestry buildings, the replacement of buildings with new-build dwellings and new-build homes, with the potential for habitat loss and fragmentation at local level, as well as impacts to local wildlife.

7.1.9 Within and across development types, a number of potential options to extend or introduce PDR relate to changes in the size and scale of development types or changes in vulnerability of occupants to flooding. These could significantly increase flood risk. Impacts on soil for example may also increase the risk of flooding. There may be reliance on private water supplies in some rural areas, with increased risk of water scarcity through cumulative impacts of development when taken together with the impacts of climate change. These have potential to give rise to significant cumulative negative impacts on water.

7.1.10 Within and across development types, several options also have potential to give rise to significant cumulative negative impacts on cultural heritage. This will depend on the siting and scale of the development and value of the asset affected

7.1.11 With the exception of options to introduce PDR for new homes in rural areas, there is potential for cumulative positive effects on climatic factors and material assets associated with the uptake of low/zero carbon technology and PDR which supports the retention and reuse of existing buildings.

7.1.12 Across all development types, the scale of these effects may reduce depending on any limitations or restrictions to be applied. Mitigation measures have been recommended for each development type. This includes retaining or introducing prior approval/prior notification, promoting guidance and limiting the scope of PDR (e.g. number of units, overall height, footprint).