The repaired frame needs more bracing than the original carpenters provided. Such bracing as there was was insufficient to arrest the gentle movement down the hill and more recently, the lunge towards the new car park in Bell Sands below the site. A rigid racking board was needed that provided both strength and qualities of vapour permeability, something conventional OSB boards are not especially good for. I alighted upon Elka Strongboard
see: https://www.ribaproductselector.com/Docs/4/25264/external/COL65821.pdf
The framed walls were sheathed in these boards, some 2500 screws securing them to the frame – the timbers having first been carefully de-nailed.