What's the law on building an extension that blocks a neighbours window?

Nick_vamob

Hi, I am interested in buying a fully detached house which is in Hendon, Barnet borough. The house is old and I am planning to extend and renovate it completely. There is the Garage which I am interested in extending forward, in line with the rest of the house, preferably a double story, as done by others on the same road. 
Next door had the same layout but they've done the side double story extension, There is a side window which opens onto their stairway from ground floor to the first floor. (Next to their boundary is the Pathway to the garden which belongs to the house which I am interned in.) If I do this extension, the second story extension will block the light to the neighbour's side window.
Is this likely to cause a rejection on my planning application?

NinjaTune

Rejection or objection?  The second is highly likely and your relationship with your neighbour may possibly suffer.

Davesnave

It depends whether the neighbour's window has been there 20 years and acquired a right to light. Then it depends on exactly how much light would be lost. It's not a simple yay or nay.

unforeseen

Davesnave said:

It depends whether the neighbour's window has been there 20 years and acquired a right to light. Then it depends on exactly how much light would be lost. It's not a simple yay or nay.

And ao whether the window is in a habitable room. 

xylophone

(Next to their boundary is the Pathway to the garden which belongs to the house which I am interned in.) 

House arrest?

Davesnave

xylophone said:

(Next to their boundary is the Pathway to the garden which belongs to the house which I am interned in.) 

House arrest?

Better than interred anyway.

Nick_vamob

Davesnave said:

It depends whether the neighbour's window has been there 20 years and acquired a right to light. Then it depends on exactly how much light would be lost. It's not a simple yay or nay.

Thanks for the reply. the window has certainly not been there for 20 years as they have done an extension, similar to what we want to do, about three years ago and the window was a recent addition. Also the window is not over a habitable room and it only lights up the staircase.

Nick_vamob

NinjaTune said:

Rejection or objection?  The second is highly likely and your relationship with your neighbour may possibly suffer.

Thanks for the reply. I know that they might possibly object, but is their objection likely to make the council decide to object our application?

Davesnave

Nick_vamob said:

NinjaTune said:

Rejection or objection?  The second is highly likely and your relationship with your neighbour may possibly suffer.

Thanks for the reply. I know that they might possibly object, but is their objection likely to make the council decide to object  reject our application?

Not unless the objection raises an issue which would be valid on planning grounds.

Fixed your response. Councils don't object. They either approve outright, approve subject to conditions, or they reject an application. In the latter case they would give planning reasons.

ProDave

The root of this present problem is the current owners NOT objecting to a window from the extension so close to the boundary overlooking their land.

Davesnave

ProDave said:

The root of this present problem is the current owners NOT objecting to a window from the extension so close to the boundary overlooking their land.

Unless it has obscure glass....