Building next to a single skin wall

[andydt]

Hi guys

Our garage party wall is a typical 1950's strip foundation, not deep enough by modern standards and just a single skin on brick. I want to upgrade this wall so it can form part of our new extension. I therefore need to build a new load bearing second-skin on the inside.

I'm thinking that the best option is to dig up the concrete garage floor, and lay a new one to raft foundation standard. So the new wall is built on this raft. The internal wall will take the weight of the roof.

I cant find anything on the internet to support this idea, and wondered if anyone had any views on this please?

 

[^woody^]

I cant find anything on the internet to support this idea

You wont.

You will need to underpin and widen the existing foundations. Or span a steel beam across on pads at either end.

 

[Footsoldier888]

Regarding the existing foundations, is it possible in practice to remove them and then dig down further or is it somewhat tricky removing a foundation below ground level and might it potentially disturb the trench too much???