Cost/disruption of supporting missing chimney breast

purplebutterfly

TLDR: how much will it cost to have supports put in for a missing chimney breast that is missing on both sides of a party wall? Both were removed 30+ years ago.  Adding steel supports will also involve removing fitted kitchen units, tiling on walls, working around the electrics etc. 

The semi-detached house we are buying has a large arch in the loft which splits in two and runs down the house.  The chimney breasts are intact everywhere except the kitchen where it has been removed at some point.  

Next door shares a wall and has exactly the same layout - right down to a missing chimney breast in the kitchen!   The owners of the neighbouring house bought it 3 years ago from an elderly couple who had lived there 30+ years and hadn't removed the chimney breast.

Our vendors have lived in the house 20 years and knew nothing about this missing chimney breast as it wasn't picked up in their survey.

In both cases, fitted kitchen units are against the wall where the breast should be.  This means that my vendor is not willing to allow a structural engineer to investigate as it will involve remove units and the false ceiling as well as fitted cupboards in the room above, to allow access to floorboards. 

The neighbours have planning permission for an extension but are not going ahead with it in the near future.  I've attached architect plans for the neighbouring property, which is a mirror image of mine 

TELLIT01

If there have been no issues with the structure in the past 30+ years why are you worrying now?

purplebutterfly

Because chimney stacks can suddenly fall, even after 30 years.  There is no ground floor support on either side of the shared wall and the building is 100 years old.  It would seem prudent to prevent a collapse if possible.  

Doozergirl

First you want to see if you can support it from within the floor upstairs.  

Even if you take the units out and replace them, it might only be £1,000 or so for the right person.   SEs usually recommend triple joists with us, so we're talking three pieces of timber and the resultant plastering from removing it to get into the ceiling.  

I'd probably remove the chimney breast in the bedroom as it's it's in a bit of an awkward position there and impeding use of the room.  Cost of that maybe £2,500?  It's the same job, but with a bit more demolition.   You may have wanted to redecorate anyway up there.  

It may well be properly supported though.  People do all sorts and the most modern way of doing it doesn't show any evidence once it's all plastered in.