Can my neighbour put a window and door in rear extension, overlooking our property?

[jaamy]

Neighbour has started to build a rear extension that runs parallel to our partition fence, leaving a 1.2m gap between wall and fence. Initially really not happy about this since we have quite a small garden (approx 6.5mx6.5m) and the view from our main living area will now be straight into the side of their extension. However, since it appears to be within permitted development (running just under 4m from the back of their house) we didn't think we could object. There has been no formal planning requested.They have a much bigger garden space on the other side of their house so is no loss of space for them.
Brickwork started today. They have left a door-shaped gap facing our property (i.e. 1.2 m from fence). When I asked him about this, neighbour said it is so he can get access to the 'dead land' that the extension will create, as the build extends right up to their boundary fence on the other side so there will be no access from the rest of their garden. He also told me that the wall will contain a window 'for ventilation' as he wants a 'through flow' of air from the entrance door on the opposite wall that faces away from our property. So door or window are not necessary for fire escape.
We had reconciled ourselves to overlooking a plain brick wall and conservatory-style roof but were unaware of the door and window. At the moment, when the builders stand on the foundations, they rise a full head above our fence, meaning that the door and window will rise at least head height above the fence, with opportunity for neighbour to stare right into our garden and living space.
Have we any grounds here to insist that they don't include the (opening) window and door? We've already asked but he says door has already been ordered. No other windows on their property face our direction and this is one of the reasons we bought our house as the small but perfectly formed garden wasn't overlooked. I can find loads of advice on adding windows to existing walls and rules for windows on first floor extensions but nothing clear regarding apertures on ground floor extensions. Will try to add image tomorrow when it's light to make more sense of my ramblings.😁
Thanks very much for any advice. Sorry it's a long post.

Great, yes we will need something evergreen so thanks for the tip.
Thanks so much everyone for sharing your experiences and advice. At least we know there is nothing we can do about the door and window regarding planning and we'll try to cover it up with trellis and climber plants.

How is it a party wall when it is on the neighbours side of the fence and 1.2 metres away from the fence?

@jaamy they can carry out the construction without seeking formal planning permission.

It isn't physically a party wall. That is just the name of the survey and agreement that has to be made if an extension is planned within a certain distance from a boundary. In particular, the depth of the foundations is significant. I can't remember exactly but I think when we did ours it was something like 2 metres apart.

Just looked it up. The distance is within 3 metres of a boundary if you plan to dig foundations for an extension or building.

Maybe they got away with it because the extension is beyond the existing foundations. Still very inconsiderate to be putting a door and a window looking right into someone's garden.
(Having said that, I can see straight into the gardens of 4 neighbours from my bedroom).

Thanks for explaining 😁

I'd go for something prickly for the times they have to go down the gap. Pyracantha for preference. You can grow it flat against the fence. If they don't want it growing in their gap, they will have to clip it. Which could be amusing to watch. They can't clip beyond the fence line, and the spikes in that thing are very sharp. The birds love the berries and it comes in nice colours.

The house we are buying has a glass conservatory that over looks the neighbors, it just has translucent glass on that side. This is somewhat unusual for a terrace but its pre-existing and has been there years at least with no issue.

Same for the bathroom window in the extension that faces them, the door also faces the neighbors too (all extensions round here do). When your building on terraces like here theres not really a way around overlooking each other and nearly every terrace has an extension.