Some years ago, Portsmouth City Council (PCC) enacted an 'Article 4 Direction' requiring planning permission for new HMOs. This overrides the usual permitted development rights a landlord has to use a normal residential property as either a non-HMO, (C3 use class i.e. family type residence) or an HMO occupied by unrelated sharers (C4 use class). There are many HMOs that do not have or require planning permission as they have been in continuous HMO use since November 1st 2011 when the Direction commenced.
The planning enforcement team are currently writing to landlords asking them for proof of continuous use - do you know what you need to do? Have you kept records to show how your property has been used?