It’s a good idea to talk to your neighbours before you start any work to avoid confusion along the way. But if the fence is definitely your responsibility and on your property, there’s no legal obligation to notify them. It’s also a myth that you need to erect a fence with the flush side without posts facing your neighbour’s property.
Clynderwen
Clynderwen is a country linear village and area, traditionally in Carmarthenshire in Wales, but carried out as part of Pembrokeshire. It lies on the A478 Tenby to Cardigan road south of the town of Llandissilio and north of the town of Narberth. Clunderwen, equating into English as "oak thicket", is called after an estate of the same name. On 1 April 2003, the village was moved from the administrative region of Carmarthenshire to that of Pembrokeshire, complying with a limit change between the regions. At the same time, a name change to Clunderwen was proposed to mirror the actual use by the area council and on road and other signs.