Greystoke wrote:
Thanks for the info guys !!

I think I'll go for a mixed approach: attach ledgers to each of the
walls and use blocks to support the frame inbetween. Hopefully this
should do the job.

the main reason I advised the use of blocks was that they are cheaper and
easier to work with than slabs and less likely to crack when under the load
of a beam running down the centre of it. either way, I'm sure that the eventual
method you choose will suffice if not be over engineered !

oh, and if you do decide to fix into the walls (bad idea imo) do make sure you
have permission to fix into the wall/s that isn't are not yours.