If however they are not and you have a large high attic, you could install a loop system; With a 28mm Flow rising from the stove into the attic, vented at that point, run across the attic, with the high point at the vent at the chimney side of the house & drop down to the heat bank.
The 28mm Return would drop from the heat bank to below the ground floor & run under the floor & rise/connect to the stove.
The loop will circulate well due to the vertital rise from the stove to the attic.......Simples!!
I always thought there had to be a rise in all areas? Am I wrong?
Dunsley call this an "Up and Under" circuit. They say it encourages back circulation, has low circulating pressure due to the dip in the return pipe and needs a "Colemans Patt" check valve fitted.
It also needs an accelerator circuit!
But perhaps RB knows different.
It would also be very difficult to install in an existing property IMO.
The layout to my old solid fuel system is similar to the OP's.
Except my joists run the right way.
My pipes are channeled into the wall incidentally and exit the right hand side of the chimney breast.
A built in cupboard hides pipe work , pump, controls etc.
I'd be happy to have chrome coated copper pipe (surface fitted) up the wall with chrome clips. But then I appreciate nicely fitted pipework that is on display.
Might not be everyones cup of tea of course.
The heat leak radiator ((1.2 kw)( Boiler output- 8.4kw/water)) in relation to the schematic would be the right hand side of bedroom 2 , T'd off 28mm.