AIBU with my neighbour about our boundary

[ThisPinkCrow]

Hi all,

We have just bought a house in London and are new homeowners. My adjacent neighbour has also bought their house at the same time as me and has begun doing works to it.

My neighbour wants to install EWI and a French drain along their main wall that is only accessible via my side access. I am seeking advice about what people would do in my position because it's not clear to me. Strangely, I can't find any examples of my situation on the internet. I would have thought this is not an uncommon thing. I want someone to tell me YABU/YANBU or if I'm missing anything really obvious here.... thank you to anyone who reads this.

The neighbours house is extended at the rear on the first and ground floor while mine is not extended at all. Both of our houses have damp issues on the ground floor. The neighbours wall is solid up to point of their extension, the extension has a cavity wall above and below. Among other things such as a French drain, as part of a multi-pronged effort to tackle this damp, my neighbour wants to install exterior wall insulation of ~ 10 cm thickness on all the sides of their house. I want to state at the offset I want my neighbours to be able to put insulation on and improve their wall. At the same time, I don't want to agree without being fully informed and regret it later.

The side wall of the main living area of their house borders the full length of my side access. My side access is only accessible to me by my gate. My side access leads straight to my garage at the very back of my garden. Their main wall is stepped out ~ 10cm in places for the two chimney breasts, before it recesses back into the main wall. At the top their roof soffits go another ~10cm beyond the chimneys, and then the roof gutters another ~ 10cm, so overall the furthest part of their structure projects give or take ~30cm from the main rendered wall.

The titles of our properties indicate an approximate straight line boundary along the wall, which then joins the garden fences and the driveway hedge/brick.

The neighbour suggested initially that the boundary follows a straight parallel line from the chimney breasts, so the gap sandwiched between their chimney breasts is their land, which means they can insulate and they just need permission for access and nothing more.

My view was that logically the boundary between our plots would follow exactly the shape of the main fixed structure which is the foundational wall, so along the main recessed wall, then following chimney breast 1, back to the main wall, following chimney breast 2, back to the main wall until it meets the garden fence which aligns with the main recessed wall exactly.

I thought that this is the boundary because the corners of their main wall precisely align with the edges of fences / connecting boundary features that separate our properties at the front drive and at the back garden. This is also the case for other properties with chimneyed walls along the same road. There is also a side access garage extension on the same road which has been built right up to the other house's wall since forever, including fully wrapping around the chimney breasts of their neighbours wall. Not that I would dream of doing this or that it would be approved these days but it seems indicative of where a technical boundary is. There is also a more recent side extension on the same road that looks like it stops not far from the adjacent properties roof structure, but my assumption there is that this was stopping some distance short of the main boundary which is the wall.

The insulation they proposed to put on would not go further than their current chimney breast depth, so in effect their wall would become straight as the parts of the main wall would be brought outwards, with insulation, to the chimney breasts which would be re-rendered but uninsulated (insulated internally) - so that the minimum width of my current side access (2.3 metres), which is set by the protrusion of the chimney breasts, is unchanged. The total area here that would be used by the insulation along this small strip that goes along their wall is only about 1.2 metres squared (12 metres length of their wall x 0.1 metres width).

I said OK to most of this, if that strip is technically my land then they can have that. Additionally I said that they can put the drain adjacent to their newly insulated wall provided that we agree the drain isn't changing the boundary, which we would both then agree follows the shape of their now insulated main wall.

The one material amendment I suggested is a ~ 2m length gap of uninsulated render at the end of their rear extension on the ground floor (which is ahead of the end of my unextended house) - because their extension has a cavity wall and the damp issues are not significant there and something can be done internally. If I wanted to do a rear extension and extend this rear extension out to the side, I would prefer to have all the space I can get even if it's just 10cm. I felt like this was a reasonable compromise where we both got enough of what we wanted - they got 90% of the insulation and the drain, I did not have the most usable width removed from my side access if I wanted to bring vehicles through. Then we would do a normal boundary agreement between ourselves and register this with HMLR which is very cheap and easy to do.

After hearing this the neighbour has paid a lot of money for a surveyor to do a determined boundary report to clarify the boundary. I said I would accept the outcome if the report explained why my thinking was incorrect, then they would seek to register the determined boundary with HMLR.

The report caveats that this is the surveyors opinion because they do not have the original plans, but the surveyor says that it's most logical that the boundary at the wall goes up to the end of my neighbours roof gutters. So my thinking is wrong, and the neighbours thinking that their boundary extends from their chimney breasts in a straight line is also wrong.

My reading of this is that all the land projected downwards from the edge of the neighbours roof gutter is theirs. Basically it's saying they own ~ 25-30 cm of my side access on the ground and all the airspace above it. The report doesn't references other houses locally or on the street, other than to say they also have projecting roof gutters, nor does it explain how the current garden and drive would be visibly offset from the roof edge were this the true boundary, it more seems to assert the conclusion based on the surveyor's experience.

If this is the true boundary then the neighbour does not need my permission to do improvement works to their wall (the insulation and the drains come within this 30 cm strip) they only need permission for access, permission which I would obviously grant if I believed the surveyor is right.

My view was that the gutters and soffits at the top could be classed as a minor trespass at most, or in effect they may be allowed to overhang the boundary because it's not bothering anyone. I was never remotely concerned or bothered about this overhang until I read their surveyor's report. This was not mentioned when I was purchasing my house but I don't blame anyone for that. I don't care about the overhang as long as the downpipes, which come down adjacent to their chimney breasts along their wall, don't discharge on my side and they do not, it doesn't cause any harm to me and if they wanted to maintain that they'd always be given access immediately.

If I accept the edge of the gutters as the boundary, this means my side access can be narrowed another 20cm by the present neighbours or (more likely) future owners if they ever choose to do so and I have no say in the matter. If I also choose to put minimal 10 cm insulation on my wall on my side of the side access (which is currently uninsulated just like the neighbours is), then in the worst scenario the minimum width along my side access at the pinch point could be reduced to less than 2 metres, and I can't really accept that if I want the option to bring vehicles through in future.

I am not really sure what happens next at this point. I just read the report and I've messaged my neighbour to tell them I don't feel like the outcomes are well explained and that if they believe the outcome, that they own ~30cm of pathway in what I perceive to be my side access, and seek to register this boundary I would have to dispute it reluctantly. I've also asked them to forward my details to the surveyor to get in touch with me so they can be better explained to me in case I'm just not getting it.

I'm still on good terms with the neighbour from my perspective, like I'm trying to be difficult, and we're still communicating with each other without any problem, and I don't have any problem with them either. but obviously this is starting to seem like it's about to go off the rails.

So.... AIBU to my neighbour here? Am I just crazy and this is what the boundary really is? If the situation was reversed and I just bought their house and they had bought mine, I do not believe I would assume that I owned part of their side access because my house's roof soffits and gutters slightly overhanged onto their side.

However, if I wanted to insulate my side wall and add a drain to reduce damp, I think I would be completely normal to want those changes and to hope that the neighbour wants to try to work with me to allow them, and to arrive at some compromise which isn't perfect but works well enough, while maintaining an agreement about the existing boundary.... that's what I've tried to do. I've not said no to anything that impacts their ability to tackle their main damp problem that they've asked of me until this point.

But if they want me to accept a determined boundary is somewhere massively different than where I thought it was in order, and then register it, in order to then tackle their damp then I'm not sure how that doesn't lead to solicitors and lots of money going up in flames. I wouldn't be bothered at all if the side access was another 20 - 30cm wider at its narrowest either but it's not and vehicles seem to only get bigger with time, equally I would be worried about what accepting this proposed boundary would do to my house value.

Thank you to anyone who made it to the end of this long post.. I tried to shorten it but it's still lengthy.

Some additional images of the front and the back where the neighbour's main wall meets their garden fence, and where the roots of my hedge meet their wall on the drive if this provides more clarity.

It's probably better if I just make a new post. As you've all pointed out repeatedly, most people will not read my first post or get to the part where I did the diagrams! But I won't do that... I think I have received enough advice from all of you here, despite my initial extended miscommunication 😁, enough to sort of carve a path forward and navigate this, so I will keep reading and replying here. Thank you everyone.

I'm not a surveyor but I'd certainly expect the boundary to run along the edge of the wall. Presumably the overhanging roof features have been there for a long time and your neighbours either own the airspace they occupy or have an easement. But that doesn't mean they own the land below them.

I thought I should add what the text of the survey actually says if that helps.

Also, the survey doesn't actually state whether this new redefined boundary shifts the boundary along the garden or drive, only along the wall. To me it seems completely plausible that if the boundary at the wall was at the roof gutters, then this would also extend backward and forwards... part of what I think is my drive also isn't my drive... but that has been ignored in the diagrams I made. The survey document itself doesn't actually draw a boundary, funnily enough, just like my post it describes it. I have to parse the text and draw one from it!

Here is the concluding text:

In similar cases involving detached properties, historic drawings—when available—have often shown the boundary running along the face of the most projecting element, such as the roof gutter. An illustrative example of this has been included for reference (attached).

Given that several elements of the (neighbour's house): the chimney breast, downpipe, fascia, soffit boards, and roof gutter—project beyond the flank wall, I am of the opinion that the boundary between the respective properties follows the flank of the projecting roof gutter.

It would not be logical for the recessed section of the flank wall to define the boundary, as this would place the gutters, chimney breast, and other elements within the airspace of (my house). Likewise, defining the projecting chimney breast as the boundary would also be illogical, as it would result in the remaining elements projecting beyond the boundary.

Furthermore, it is common in UK construction for chimney breasts to be built internally without external projection, which could explain this arrangement.

Considering that other properties on (our road) exhibit similar characteristics, it is reasonable to conclude that this boundary positioning is consistent with the design of the street (I don't know why they say this, it is not elaborated on in the report)

Based on the above, my professional opinion is that the boundary follows the flank face of (neighbour's house), aligning with the edge of the projecting roof gutter.

Thank you all again. I will come back in the morning and reply to what I missed. 💤

I cannot see any DPC on the last picture, this is the likely cause of the damp issues. Also the render on the house could bridge any existing DPC which would also contribute to the rising damp.

Insulating the house would not solve this problem and would make it worse.

The neighbour plans to do multiple works related to the damp... adding a new DPC, adding a french drain that goes to the public sewer, both of which I am informed help reduce structural damp penetrating from the ground by capillary action through gaps in the wall structure.

Exterior insulation from my rudimentary understanding is relevant if the damp is superficial by internal condensation on cold walls, but it won't solve structural damp. It is more commonly needed to reduce heating costs / improve EPC. But they never mention heat loss, ever, even when I mentioned my interpretation to them, they think it's going to solve their damp problem.

So they are trying to tackle both the structural and the internal, it sounds to me like the structural is their root problem. But even with that, a decision has to be made on the insulation before they can put the drain in, and this new boundary information muddies the waters.

All that said, I am not an expert on this and I've lived in flats my whole life. I don't want to tell my neighbour that they should be do something different, it doesn't really seem like my business. If they are keen on insulation, even if it is not optimal for them, as long as I can live with it then I will find a way to give them that insulation.

^ This often in life simple logic applies your garage is the most reliable indicator of where the bounty is.

the gutters area trespass, which is not uncommon.

i would resist any further encroachment.

where was the TLDR? diagram? did read about half way before giving up!

I have no advice, but a PowerPoint presentation? And taking feedback on the chin? You’ll do well here.

Can you have some parking disputes with your new neighbours so we can have more diagrams?

Anyway, as you were…

I couldn't get past EWI.

The garage is up against the fence, but there may be a small gap there. I admit I forget about this when constructing that diagram.

I had not previously thought of photographing that, there is a overgrown hedge there at the moment that obscures the gap. I will push that apart and take a photograph tomorrow.

The below is the only image I have of that at the moment.

Is that pebble dash render in the photo? It may well be causing the damp. Take it you have solid walls, no cavity, possibly with a cement plinth at the base? If the render covers the damp proof course (which it should have, they've been compulsory in London since 1875) it can track up moisture.

If they want French drains, they can put them on their own property, not yours, the cheeky fuckers.

Do not give them any land.

Why do you say that? They are putting drains on their property, all around - it's just this is on my side.

The only points I mentioned to them were:

1. We need to make sure the drain doesn't change the boundary and legally agree it. So if I ever need to remove it for essential works I can do so without question (I doubt I ever would, but I need the optionality since the drain impacts ability to extend to the side), they may install it but the drain is mine.
2. Agree legally that it's their responsibility to maintain.
3. Put in a grate/mesh structure of some kind on top of the French drain that is on my side, which is steel/iron so that the level is still flat with the access, and that there's nothing I can ever do to damage it.
4. Ensure any of the water collected does not deposit on my side of the boundary, and that it does not overflow from their side.

But this whole topic comes after the insulation, right, because they need to do that first before they can do the drain.

I said to them I was prepared to split the costs of additional materials for putting in the grate for the French drain, since everywhere (all around their house) they want to use a pebbly/pea gravel/shingle surface for the French drain, it would only be my side with a different material.

Too many words, be more succinct. I'd seek some legal advice and wouldn't allow anything that needed to be accessed on your property. Sounds like a recipe for disaster.

Oh sorry, I thought that they wanted the drain on your side of the border.

They do want it on my side of the boundary. This assumes that the ground area within my side access is on my side of the boundary!

It's on page 2 near the start, sorry for the long post.

I have never seen a French drain less the 30cm/1 foot in width. If they put it next to their wall, it will encroach onto your land.

I think the neighbours need to pay for a party wall surveyor. You pick the surveyor, they pay.

None of this work is for your benefit, it shouldn't cost you a penny. In fact they should be paying you for the use of your land for their scaffolding.

I forgot to mention, the French drain width they suggested is 10 cm. The first time I heard of French drains was when they told me, so I don't pretend to know anything. All I know is that at the point of drafting an agreement for these works I would have this in writing from them. So it would be 10 cm of insulation up to their existing chimney breasts, then another 10 cm or so for the drain at the ground level.

I'm not going to charge my neighbours for scaffolding... that sounds like it would spoil relations to me. Is that normal?

Currently in the agreement I wrote to them, it's pretty simple since they are just repairin their roof... we agree scaffolding can be put up between X and Y dates, and make sure the contractors are insured and they don't do any damage, lock the gates etc, otherwise access can be revoked between those dates.

Regarding the party wall surveyor, Is that different from a boundary surveyor. I thought party walls were for terraced or semi-detached houses where a wall is shared in the same structure, you are saying that a party wall is instead any wall that lies on a boundary and that I am misunderstood about this? The neighbours have paid for a determined boundary report from a boundary surveyor, I did not contribute to this.

Ok, finally going to sleep.

I have attached another diagram that shows the works my neighbour is wanting to do, which together with the diagrams earlier might be helpful. Basically, so far, provided we do it correctly and agree things legally, I am not trying to prevent them from doing this. The determined boundary report however is something I would be obstructive about without further explanation..

+1 for clarity

Your neighbours are utter piss-taking cunts who are trying to steal your land and when that didn't work they oh-so-kindly offered to buy it. Land you need for access. Forget being friends with them, that ship has sailed long ago. Don't give them any of your land - they want it, they buy it. Don't listen to their surveyor, they've most probably paid someone to write what they wanted them to write and they've probably also lied to you about how much it costs, which is why this person has done zero work on actually establishing where the boundary might be.

It's basically the property version of negging. They're trying to make you so grateful for their minimal theft by making out they can create a bigger theft because according to their mate down the pub the surveyor it's all theirs anyway upto their gutters.

Why on earth are you talking about letting them out a drain on your land for free too?! It might be their drain but it'll be on your land. Why would you do this? It's creating hassle for yourself and the drain is for their property not yours (unless I've misunderstood that)? Is this drain going to be able to take the weight of a car driving over it without cumulative damage occurring?

Don't do anything that devalues your property by creating a situation where you can't use your garage for its intended purpose, just to help them out, the people who have already demonstrated they would happily steal land from you. You owe them nothing.

When dealing with such people, they're never grateful for anything you do. Their sense of misplaced entitlement won't allow for that. They won't cut you any slack in future. Any concessions you make to people like this are seen as a sign of weakness and as you're already experiencing, they don't back off glad to have been given something for free, all that happens is they pile on even more pressure and try to get even more out of you. You're nice, they're not - don't judge them by your standards. Watch your back.

I gave up after a few paragraphs. I just lost the will to carry on.