You can extend most houses in Eynsford, but less freely than the absence of a conservation area suggests. Around forty buildings are listed. There is no conservation area at all. The whole village sits inside a protected landscape. Neighbours file plans at a steady rate, so it can be done, with paperwork.
Eynsford has 39 listed buildings: one Grade I, none at Grade II*, and 38 at Grade II. Listing covers the whole building, inside and out, so almost any change to a listed home needs listed building consent from Sevenoaks District Council on top of any planning permission, and that includes windows, doors, internal walls and fireplaces. Doing the work without consent is a criminal offence, and the duty to put it right passes to whoever owns the house next. For a village this small, 38 Grade II buildings is a lot of old fabric with legal protection. If the house you want is one of them, the original windows are protected by law.
There are two scheduled monuments in and around Eynsford, the strictest tier of protection in England. They matter mainly to owners whose land runs up to one, where even digging for foundations can need separate consent.
People do extend and alter homes here, and often. Around Eynsford, 450 planning applications were lodged between April 2024 and June 2026, and 214 of those in the last twelve months. Those are applications, and the figures do not record how many were approved. They do show plenty of neighbours testing the rules every year.
In practice, an unlisted house can often take a modest rear extension or loft conversion under permitted development, the national rights that allow some work without a full application. Eynsford has no conservation area to restrict those rights further, but the whole village lies inside the Kent Downs Area of Outstanding Natural Beauty, where some permitted development rights are narrower and the council looks harder at anything visible from the countryside. A village with a ruined castle and a Roman villa down the lane has skipped the conservation area and gets the full protected landscape instead. Check the Historic England listing and the house's planning history on the Sevenoaks District Council portal while you are still deciding. An extension a previous owner was refused is the best guide to what the council will say next time.
Your freedom to extend in Eynsford is middling. An ordinary post-war semi can usually grow, while a listed cottage will need patience and paperwork.