Schizophragma climbs via aerial roots, ie it sticks firmly to whatever it is climbing, so yes, it will stop you painting the wall if allowed to touch it. It needs flat surfaces to adhere to. It can't twine around thin structures, so if you want it on a pergola, unless the members are relatively flat and wide providing a good substrate, you'll need to tie it up in some way. The branches become fairly woody and stiff and and it becomes difficult to rearrange branches once they have matured.