You need to work out whether your neighbour does actually benefit from a right to light and if so whether your proposals do actually breach that right. A right to light is a right to adequate daylight from the sky. As a general, though not conclusive, rule this means half the area is entitled to a minimum standard of light which is equivalent to the light from a standard candle at one foot&amp;’s distance. Expert surveyor assistance will be required in calculating this.<p></p><p>Do any windows in your neighbours building overlook your property and would your development proposals block the light to this extent? If so, check your title deeds. Do they contain a restriction against building in such a way as would restrict the neighbour&amp;’s rights to light? </p><p>Is your title subject to your neighbour&amp;’s rights to light? If not, your neighbour may have acquired a right to light by prescription, i.e., 20 years use without interruption. Enquire locally as to how long the neighbours current use of the property has continued. If it is fewer than 19 years then there is a good chance that you can defeat the neighbour&amp;’s claim. </p><p>If you are not going to develop immediately …