Yes, but in much of Bushey the council and the ground both get a say. There are more than a hundred listed buildings. Nine conservation areas cross the map. Shrinking and swelling clay lies under most of the town. The neighbours keep applying anyway, and most of them get there with paperwork and patience.
Historic England lists 114 buildings across the Bushey area: none at Grade I, 4 at Grade II* and 110 at Grade II. Listing covers the inside of a building as well as the outside, so changes to a listed home need listed building consent on top of any planning permission, and that includes internal walls and windows. Bushey has no Grade I buildings and only a handful at II*, so most of its heritage is ordinary houses on ordinary streets, protected all the same.
Nine conservation areas fall within the wider Bushey map, among them Bushey High Street, Bushey Melbourne Road, Bushey Heath High Road, Bushey Heath The Lake and Round Bush. Inside a conservation area, changes that elsewhere would go ahead without an application can need one, especially anything visible from the street, and demolition and work to trees come under extra control. Hertsmere council's conservation-area maps show whether a particular house falls inside a boundary, and that one fact decides how much paperwork the project needs. The town was recorded in Domesday as Bissei and has kept a long record of what it allows ever since.
One scheduled monument falls within the area. That is the strictest level of protection, and it mainly matters for land next to the monument itself.
Hertsmere received 2,348 planning applications in the area between March 2024 and June 2026, 949 of them in the last twelve months. Plenty of Bushey households are clearly altering their homes, and on most streets someone has drawings with the planners.
The ground is the other constraint. The British Geological Survey puts the shrink-swell hazard at class 3, its published classification for clay that moves as it wets and dries, and about 73% of the area's postcodes are at that class or above. For an extension, that means deeper foundations than the builder's first quote may allow for, and a structural engineer's view on nearby trees and drainage. The clay was here long before any extension and will still be moving after it.
Outside the listed buildings and conservation areas, a modest rear extension may fall under permitted development, the national rights that let some work go ahead without a full application. Inside a conservation area, or on a listed building, many of those rights are reduced or disappear, and the same extension becomes a formal application. Two Bushey houses only a few streets apart can face very different processes for the same rear wall.
Extending in Bushey is possible, but less freely than most buyers expect. Heritage controls are dense, the clay needs proper foundations, and a straightforward permitted-development job is the exception.