Building side return extension when neighbour has a side bay window

Onebatmother

Hello - very grateful for any help. We're considering buying an end of terrace and building a one story side return extension, preferably with a standard rather than glass roof. The neighbour (semi-detached) has a bay window at the side of their house - it must already be pretty dark because there is a boundary fence. Will this likely mean that planning is refused? We cannot go for permitted development for other reasons. 

Onebatmother

To add - their bay window looks onto their side passage and is approx 1.5m from the boundary. Only the last 2/3 of the bay is facing the side return that we would build into - the first 1/3 looks onto the existing wall of the main house There is, additionally, a 6-foot fence in front of the part which looks onto our side return.

lincroft1710

Talk to the local planning officer, they are in the best position to advise

Onebatmother

Unfortunately we have the slowest planning dept in the UK and they charge you for pre-planning, and it's v expenive - No friendly chats!

anselld

I had one refused in similar circumstances and it was also refused on appeal.
Why not permitted development?

[Deleted User]

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