Usually yes, but the old parts of the marsh come with paperwork. There are hundreds of listed buildings across the wider area. Eight conservation areas cover the historic cores. A string of scheduled monuments is dotted across the fields. Neighbours put in planning applications almost daily, so extending clearly isn't forbidden. It just isn't automatic.
The wider Lydd area has 222 listed buildings. Nine are grade I, 6 are grade II*, and 207 are grade II. Grade II is the everyday listing, and it's the one that turns replacing a window into a formal application. Listing covers the whole building, inside and out, plus some attached structures. Any change that affects its character needs listed building consent on top of any planning permission, and starting work without it is a criminal offence, not an oversight to sort out later. For a listed home, every decision about materials, windows and layout goes through the council.
There are 8 conservation areas across the wider area: Lydd itself, Dungeness, Littlestone-on-Sea, Brookland, Newchurch, Old Romney and two in New Romney, around Cannon Street and the High Street. Inside them, the council cares about how a street looks, not just about individual buildings. That can mean tighter rules on extensions, demolition, roof changes and anything visible from the road, and some rights that apply elsewhere may be restricted. A house on the edge of a conservation area and the same house just inside it can face very different planning conversations.
There are also 13 scheduled monuments in and around the area, the strictest tier of protection, and they mainly matter for land next to or on top of one. The list runs from sections of the Royal Military Canal to a set of concrete acoustic early-warning devices built to hear aircraft approaching. They weren't designed to pick up anything as small as a garden-room application, but the protection around them is strict all the same.
People here extend all the time. Across the wider Lydd area, 1,906 planning applications were lodged between March 2024 and June 2026, and 869 of them came in the last twelve months. That is the most useful evidence a buyer has: people here keep asking to change their homes, and they're prepared to do the forms to get there. The count says how often people apply, not how often they get what they asked for.
For a house that isn't listed and sits outside a conservation area, many modest changes can be done under permitted development, the national rights that allow certain extensions without a full application. For anything listed or inside a conservation area, assume consent is needed until the council says otherwise. Before buying with plans in mind, check the property's listing status and whether it sits in a conservation area, and ask the council whether permitted development rights still apply at that address. A lawful development certificate settles the question in writing for a small fee, and it costs a lot less than taking a new extension down again.
Freedom to extend is limited across much of the area. On an ordinary bungalow outside the heritage cores it's straightforward, and in the historic centres it goes through the planners.