side extension query

[JulietRomeo]

Hello, my neighbour has a detached property with a converted garage on one side which has been converted into living space with a bay window at the front and 4 square/domed rooflights along the flat roof which are equally spread along the depth of this now living space.
On my side, I would like to extend my much smaller property which has a lengthy driveway along my side of the boundary into a double storey extension (living space on the bottom, bedrooms on top). The depth of the property would be identical to the neighbours property. However due to the roof lights would my neighbour be able to argue to veto my plans for a double storey and effectively reduce them to a single storey in order not to impact his roof lighting setup?

The neighbours property is a rental so I don't have an easy 'go knock and find out' option unless I press the agents for a chat.

Thanks
JR

[JulietRomeo]

Hi, to allow light into the landing area a window is likely on the top floor about halfway down the depth. Could be a frosted one if this was the determining factor.

[JulietRomeo]

Yep bingo. Perhaps could have been clearer with my opening mail.
Side window or no side window it still a stonking wall going up that will affect their light lumens entering the roof lights I'm sure...

[JulietRomeo]

The neighbours single storey side extension is ~6 inches from the boundary, with their guttering then nudging right upto the boundary itself. I would be looking to do similar on my side.

I'm awaiting the owner to contact me as agents can't give out their details.