Decking attached to my fence

[GarethSouthgatesWaistcoat]

Hoping someone might know the answer to this

My not-great neighbours installed decking in their small terraced garden roughly 6mo ago. No issues with height (30cm or less) but I've noticed my fence is starting to lean into my garden at that point and at least one of the posts appears wet/rotten at the base.

The fence is my boundary fence and is a couple of years old. It was installed by a fantastic chap and is (was) really sturdy. I'm almost certain their decking has been attached to my fence leaving no gap for maintenance.

I've never had decking so not clear on the ins and outs. Is it normal to attach it to the neighbour's fence? They know it's my fence as they saw it being installed (it's definitely my boundary to maintain). They had a company install their decking. It's on a base but I'm certain it abutts the fence at either side with no gap.

I've tried googling but I can only find discussion on height of decking which isn't the issue here. I can't find anything definitive about attaching decking to a neighbour's fence without permission.

If they were reasonable I'd approach them.

It's been very dry here in the SE since spring which is also confusing me - why would my fence post/gravelboards be damp? Could the decking be responsible?

Thanks in advance

Sorry I should've added I'm unclear whether it's fixed to my fence or abutting it. There is no gap either way.

As long as the decking is within their boundary there’s nothing you could do, but if it’s attached to your fence in any way then I think you could complain.
When we had decking installed , in our last garden, it was on a sturdy framework that stood alone. There was a gap between the house and deck.

They cannot attach ANYTHING to your fence or even paint it without your permission

Whoever put the decking in took the easy route if they attached it to your fence. As a pp stated, they've no right to do that or attach anything to your fence.

Thank you all! I live alone and get really anxious over stuff like this

They're not the nicest people so I like to be prepared.

They may have assumed the fence was jointly owned between the two houses, even if they know you paid for it. People don't always realise these things. You might need to make the point that it's your - anything you have to prove that would be useful so you can give them a copy.