It is illegal to obstruct a private entrance:
http://www.northamptonshire.gov.uk/Transport/r oads/driveway.htm
Obstruction, for the purpose of causing wilful or unnecessary obstruction that can be dealt with by law includes stopping or parking:
* near a school entrance
* anywhere you would prevent access for Emergency Services
* at or near a bus or tram stop or taxi rank
* on the approach to a level crossing/tramway crossing
* opposite or within 10 metres (32 feet) of a junction, except in an authorised parking space
* near the brow of a hill or hump bridge
* opposite a traffic island or (if this would cause an obstruction) another parked vehicle
* where you would force other traffic to enter a tram lane
* where the kerb has been lowered to help wheelchair users and powered mobility vehicles
* in front of an entrance to a property
* on a bend
* where you would obstruct cyclists� use of cycle facilities except when forced to do so by stationary traffic obstruction that can be dealt with by law is: