How about a repairing station, similar to the food station for thralls.
Especially on PVP its very annoying to run around afer the raid time and fix every building part with the repair hammer.
The suggestion is a repair station, that is inactice during raid times.
You place the repairing mats inside and the station will start repairing the next connected building parts.
Maybe you need to add a thrall, to make it more realistic.
Best would be if the number of mats you need to repair everything is shown.
I dont know if it can be combined with the decay system, so the complete building is affected.