When planning permission is granted for an extension, planners should take full account of neighbours’ amenities, including any impact on light. In theory, where there’s a genuine ‘right to light’ issue, this should prevent planning permission being granted. Here, with permission granted and the neighbour claiming a ‘right to light’ issue, it appears either the planners have slipped up and there really is a problem, or they’ve assessed the position correctly and the neighbour is exaggerating.
The problem is that you need a specialist ‘right to light’ surveyor to tell you whether there really is a problem here – which means spending some money on professional fees. There are firms of Chartered Surveyors who specialise in the area and a suitably qualified and experienced surveyor should be able to tell you whether there is likely to be an issue. If so, you might need to adjust your extension plans. If not, you can proceed, as your neighbour will not be able to secure an injunction unless there really is a serious problem. Minor issues with ‘rights to light’ tend to be settled via the payment of compensation, but before doing anything, take advice. This is a highly specialist and technical area of law, so don’t take any risks.