ETC

How on earth did this happen? - can you post a bit more detail.

When the flood coming?

Don’t build a cold flat roof.

Build that wall (or all the walls) in cavity wall construction with an outer leaf of brickwork - the brickies can build this wall overhand. You will only be able to place the outer edge of the foundation for your wall next to the foundation for the party wall. I am assuming that the party wall will have a (strip) foundation with a projection of at least 150mm - your (strip) foundation will also have a projection of about 150mm. This could mean that the outside of your new external wall could be located about 300mm from the party wall. There are other ways to do the foundation but if you need to stay away from the party wall you will also need to stay away from any foundation. Put an ACO drain in the gap. Unfortunately if leaves get into the gap you will need a long stick!

What are you building?

New cavity wall with facing brick outer leaf and an ACO drain down the "gap". Mono-pitched roof (high part of roof to party wall).

Quick question - what support do underground drainage pipes need where the house has piled foundations?

Can you post some pictures/sketches of what you want to do?

Take the chimney down and rebuild it with liners, lead trays and flashings.

Why?

I think your BCO is being a bit disingenuous by telling you that the porch creates inner rooms. If this was the case them thousands of houses up and down the country would need EEWs to all habitable rooms not just on the first floor but on the ground floor.

If you have external doors to the kitchen and fire escape windows on the first floor you should be fine.

Rubbish. It's not a habitable room. Look at the definition in Approved Document B. In any case if this were the case every single room on the ground and first floors in all houses all over the country would need EEWs. Go back to him and ask him for a definition of a habitable room/space. EDIT: I have just looked at your floor plan. The Living Room is the inner room (to the first floor bedrooms which I am presuming if this is a new house all have EEs) - not the porch.

@Thorfun @AliG Thanks for your comments. Watch this space - amended version coming soon.

My thoughts.

My thoughts.

Too low. The DPC in the external wall needs to be a minimum of 150mm above FGL. Your BCO will reject it.

Flogging a dead horse comes to mind. Why do you think you are due LDs? Was this a JCT Contract with a pre-determined completion date and was an extension of time requested or granted. As other posters have said - you will need to keep the contractor on side to carry out any remedial works.

My bad……if it’s heated you should insulate it……….I wouldn’t bother putting in heating. Just put a jumper on.

Remove and redo.

FFS it’s a detached non-habitable building with no heating. No insulation is needed. Tell your BCO to wise up!!!

Tomato - tomato.