Overshadowing

Overshadowing vs loss of light

Loss of light generally concerns daylight reaching windows and habitable rooms, while overshadowing generally concerns the impact of shadow on gardens, patios and other outdoor amenity spaces. A development can cause meaningful overshadowing to a garden without technically failing a window daylight test, and vice versa, so it’s worth being precise about which you’re objecting to.

Where daylight and sunlight assessments are undertaken, they often draw on BRE guidance, which commonly uses the spring and autumn equinoxes as reference points. The approach adopted can vary between councils and developments — a proposal that leaves a garden substantially in shadow even at the equinox is a stronger case.

What strengthens this objection

• Identifying which specific outdoor space would be affected, and roughly what proportion of it and for how much of the day
• Describing the current use of that space (a main garden or patio used daily carries more weight than an unused side passage)
• Relating the shadow directly to the proposed structure’s height, depth, and position relative to the sun, rather than just its overall size
• Requesting or referencing a shadow/sunlight study if the application is large enough that one hasn’t already been submitted

Where it tends to fail

A brief, partial reduction in afternoon sun to a corner of a garden is unlikely to be treated as significant on its own. Objections that describe the development as simply “blocking the sun” without saying which space, for how long, or at what time of year carry far less weight than ones that engage with the actual pattern of shadow the proposal would cast.