Concrete shed on boundary wall.

Seve OB

Would appreciate any opinions on this please. Not even at the planning stage yet, just thoughts for now but got to get cracking soon.

I have a barna shed up in the corner of the back garden, it’s to small for requirements and has to be replaced as it is rotting away in places. All boundaries are wooden fence except a neighbour to the side (Semi-D) has an extension on the back of their house. When it was built by the previous owners, they consulted with us and we were happy for them to build on the boundary wall and take down the fence. No issues with this, I’m just trying to give the full picture. So head up along the same boundary to the back corner and the same neighbour has indicated they might put in a concrete shed and we briefly discussed sharing the boundary wall for each shed. I don’t think they are planning anything immediately, more long term, but we gotta move soon, which kinda suits me as I can plan it the way I want it and I don’t think they will have any issues with us using the boundary. It’s a small enough garden, so I estimate using the boundary will give us an extra foot or so on back and side walls.

Now the neighbour behind is rented, but the owner previously built a wall down their side, but inside the boundary. I spoke with him when he was doing it, there was troublesome neighbours (dirty) so that’s why the wall went up (long before the existing tenants moved in). I got the impression he would have preferred to use the boundary. Anyway he did indicate that he might someday build a back wall, and I told him if he was going to do it, I’d be happy if he wanted to build on the boundary. Long before I ever thought I’d want to build a shed here myself. Anyway, he never did. I do plan to try and talk with the tennents and owner, of course, though the owner was elderly and I don’t know them at all, just to say hello.

What I would like to do is and forgive my lack of technical terminology, build a shed but the wall at the back would be higher than existing fence by about 1.5-2foot. Wall at the front would be maybe 2 foot higher again, so sloping away from my house. I’m guessing the back wall should be slightly higher than the lowest point of the roof so it won’t drain or hang into their garden, I’ll probably run a down pipe and maybe a water butt against the back wall.

Now it gets a little messy perhaps because we are not aligned, as in that’s only half my back boundary and I don’t even want the shed to run that full width. There would be about a 2metre gap between shed and his existing wall which I’d be happy to flesh out. Then the rest of his back boundary runs across the neighbour who is considering the shed.

Of course there could be another slight problem when I whip down the barna shed I think the back wall might not be at a 90degree angle with side wall, so not sure how easy that will be for any build.
I know the simplest thing is to build inside the boundary But I’m really just trying to make the most of the space. If I do go inside, I think I’d ask them can we take the fence down temporarily so that we can get right up to it and make sure it gets plastered etc.

Lastly and the auld how long is a piece of string question is how much might I be looking at, and is it something a reasonably competent DIYer could tackle.

Probably talking about 9 foot tall back wall, 11-12 foot at front, 12 foot deep and 10foot wide.