i am toying with the idea of :
(1) converting the clay tiled pitch roof that has been sheltering my two-storey corner terrace into a flat roof with a roof garden (with trellis) and a small utility room and a lavatory (optional); and of course
(2) stair case leading up to the sky roof.
now, would anyone know if i should approach an architect or professional engineer or contractor or interior designer for such works?
would such works require approval from bca (or whatever authority there is) and if approval given a straightforward matter?
if anyone knows the estimated cost of embarking in such works, pls do share for budgetary purpose.
thank you in advance