To share or not share a wall?

[Katjolo]

Advice please. Live in a semi detached. Planning an extension. Would you proceed with a shared wall or own wall on boundary?

Most websites suggest shared wall. Builders have all said, own wall. Also when building an extension should I prepare for my entire garden to be ruined? It's a long garden.

Help please!

Well you can only have a shared wall if your neighbours agree, so might be worth asking them first?

It's only beneficial to them if they are planning their own extension so can use the same wall to build off.

Neigbours have agreed with either option. They are planning an extension at a later date but plan to extend further than us. Is this a potential problem?

Most houses which I've seen with a shared wall are extending to the same point.

In that case the party wall would have to be extended, which might have implications for your finished extension.

It would probably only work properly if both extensions were built at the same time.

On a side note, a shared party wall would automatically mean that the extension will require planning permission, even if the extension met all the requirements for permitted development.

Even with the party wall agreement signed?

Another concern is if we build within our boundary and they do the same at a later date... will there be issues with damp etc in the future due to a small gap between both walls.

Not sure what you mean?

PWA is separate from the Planning system.

PWA could ensure a decent finish to any work on your property, but if it has to be partially dismantled to key in the new wall eg, the finish will never be quite the same eg damp issues etc

We have permission via permitted development and party wall signed. We plan to build before neighbours (although they may not build at all). Trying to weigh up options.

PD only applies for development within your curtilage (your boundary). If any part of the development is over your boundary (eg a party wall) planning permission is necessary.

We built in from the boundary so no one could tag or add onto out wall.

If you share the wall then party wall agreement needed for future work to the wall whereas if your own the wall exclusively you can alter it more easily. I am watching with interest though as we had an extension built under permitted development within our curtilage but neighbour has now created a party structure on top by putting the guttering for their extension on our wall without permission!

Rwalker, how much in from the boundary did you need to build to avoid the neighbour tagging onto your wall?

@rwalker

We built in from the boundary so no one could tag or add onto out wall.

Have you had any problems with debris building up in the gap? Or damp?

@Seeline

PD only applies for development within your curtilage (your boundary). If any part of the development is over your boundary (eg a party wall) planning permission is necessary.

I never realised this. Thanks for sharing.

We had this situation and built a wall which two years later our neighbour used to build his, paying us about £1500 if I recall correctly (all assessed by a Party Wall surveyor, and PWA put in place).

In terms of your garden - yes, prepared for it to be a builders’ yard and to give it a complete overhaul. We’ve extended twice and had to do this twice!

@Katjolo
next doors haven't build but they are very old and i'm sure next person would as kitchen was very small.
There's a fence and a gap of about 5 inches about once a year it get a hand brush on a clothes prop and clear it out few leaves and a pigeon got stuck once but got that out .
no problem with damp

Great to hear. Researched loads today and swaying towards own wall.

We are currently building an extension at the same time as our neighbours, and agreed on a shared wall. We are extending to different points (they are going further than us) and no issue with that, although not sure if maybe it would be more difficult if the build wasn't simultaneous. Good thing about sharing a wall is you end up with more internal space. Our next door but one also has an extension but not to the boundary, so a small gap. Apparently it is a bit grim, something about rats...

Oh yes and the builders told me the garden would be hardly affected, but in reality it has been completely trashed!

Interesting points. Thanks.

We went for own wall. To do otherwise would have meant taking down an old stone wall between us, instead we underpinned it £5k.

Builders, architect, everyone really said own wall.

We’ve just done an extension building on the boundary wall - the neighbours do have an old extension just a little inside the boundary wall on their side. They agreed and we drew up the party wall agreement between us.
They may build on onto the wall at some stage but they will not go out as far as we have due to the shape of our respective gardens.

We gained about 10cm internal space by wall over the boundary. Needed pp as did loft under permitted development. Garden was trashed.

Forgot to add - garden trashed!

And yes garden trashed. We needed replacement drains though ....ours were 120 years old and no manhole covers. We’d already had one cracked pipe to deal with.

I better add new garden to my budget 🙊

The builders took away almost all our topsoil ... they swear they’ll replace with good stuff. There’s paving included in the price...