Extractor fan on wall going into neighbors garden

[Emmszy]

We have an extractor fan for a downstairs cloakroom that exits onto a shared wall going into our neighbours garden. They have just coincidently informed us they are planning to extend (we are terraced houses so the extension will connect with us.) Are we obliged to move the extractor fan outlet? It was already there when we moved in and next door was renter-occupied.

Can you sketch the layout, I can't visualise what you mean.

I think a gap between the existing and extension wall is required so your fan should be ok.

I think building regs in the UK state that you shouldn't have the fan exhaust discharging onto someone else's property. You might want to ask them what they propose to do about the vent when they build over it - I assume that's what you mean will happen from what you've posted.

Sorry LizzieMacQueen, no idea how to sketch on here!
Thanks wowfudge, I think they are assuming that the vent is our problem, not theirs. From what I've read about building regs it is not clear about extractor fans

You may need to re route the fan.

Our kitchen fan exits into the neighbours garden.
They have built a lean to type building in their garden next to the fan, but I presume they’ve left a gap?
I can’t tell without going into their back garden.