Most Dursley homes can be extended with the ordinary paperwork. A little over a hundred buildings are listed. Two conservation areas cover the older parts. The neighbours are in the planning queue constantly. The rules are strict in the old core and much looser out in the closes.
Historic England lists 126 buildings in the area: two at Grade I, five at Grade II* and 119 at Grade II. Listing protects the whole building, inside and out, so even small changes like a new window, a stripped-out fireplace or a moved internal wall can need listed building consent on top of any planning permission. Work done without it is a criminal matter as well as a planning one. With 119 of them at Grade II, most listed homes are in the band where the council is careful but not immovable. The two Grade I buildings are a different conversation, and nobody is putting a kitchen extension on either of them.
There are two conservation areas, Dursley itself and Woodmancote. Inside them, some changes that would be automatic elsewhere need permission, and the council judges new work by whether it keeps the character of the street. Check whether the house you're considering is listed and whether it falls inside either boundary, using Stroud District Council's maps. Outside those lines, a post-war semi answers to much simpler rules than a cottage a few hundred metres away.
Stroud District Council received 586 planning applications for the area between April 2024 and June 2026, and 257 of them in the twelve months to June 2026. Those are counts of applications made, and how many were approved isn't part of that record. They do show what Dursley owners actually do with their houses. With 257 applications in a single year, plenty of people here are getting on with their loft conversions and rear extensions.
In practice, most of the town's modern housing can use permitted development, the national allowance that covers many single-storey rear extensions, loft conversions and outbuildings within set limits, without a full application. Those allowances are narrower inside a conservation area and don't apply to listed building works at all, so a listed home or one in the old centre will need a formal application for most changes. For a semi on the edge of town, the usual first step is a lawful development certificate. For a listed house near the Town Hall, it's a long talk with the council's conservation officer.
Your freedom to change a house in Dursley is middling. Most of the town lets you build, while the historic centre and its listed buildings expect to be asked first and will take their time answering.