Yes, for most homes, though the paperwork still has to be done. There isn't a single Grade I building in town. There's one conservation area. The neighbours send in hundreds of planning applications a year. Heritage rules are light in Crowborough, and the planning queue is busy.
Crowborough has 45 listed buildings: none at Grade I, 6 at Grade II* and 39 at Grade II. Listing covers the whole building, inside and out, so changing a listed home means listed building consent on top of any planning permission, and that includes some work you might think too small to need it. Replacing windows, knocking through a wall or swapping a staircase can all require consent in a listed property. With only 45 in a town this size, the odds are that your house isn't one of them. If it is, you'll know before you exchange, and your conveyancer will have mentioned it more than once.
There's one conservation area, and it takes the town's name. Inside it, alterations to the outside of a house get looked at harder. Work that would pass without comment elsewhere in town may need an application, and whatever you build has to fit the character of the area. Whether any extra local restrictions apply on top isn't covered here, so check the house's exact status with Wealden's planning team rather than assuming either way.
The area has three scheduled monuments, the strictest protection tier there is. They mainly matter if your land is next to one, and most back gardens aren't.
The neighbours are at it. Between April 2024 and June 2026, 1,040 planning applications were submitted in the area, 424 of them in the last twelve months. That's the paper trail of a town that extends, converts and adds on as a matter of routine, and it gives you useful evidence. Search the planning register for your own street, and you'll see what's already been tried on houses like yours.
What that means in practice: outside the conservation area, on a house that isn't listed, a lot of smaller work may fall under permitted development rights, which let you build within set limits without a full application. Anything larger, anything on a listed building and anything visible in the conservation area needs the proper route. Before you design the orangery, check the house's listing status, whether it's in the conservation area, and whether any earlier permission removed its permitted development rights. Plenty of buyers find out about the last one only after the builder has quoted.
Crowborough sits in the middle for freedom to extend. The heritage burden is light, but a listed handful, a protected town core and a busy planning register mean you shouldn't assume any project will get through without being read.