sm_jamieson wrote:
My extension will be built against the neighbours party wall, so
visually, I will be extending the rear wall from her extension across
mine. Her extension is built in the older 73mm bricks I think,

They aren't 73mm bricks, they're probably 3" ones.


My design is standard 65mm bricks and 215mm high blocks inner leaf. The
design is to use wall starter plates anyway, to avoid cracking with the
different foundations, so there will be some visual discontinuity there
anyway. But should I just use 65mm bricks and have the join looking
rather obvious, or try to use the 73mm bricks ?

You can get bricks that are taller than 65mm, if you use them
the job will IME look *much* better.