K MISC WORK (4980)
K-1 "Downspouts :
1. Drainage shall comply with relevant American Standards or BS 6367.
2. Downspouts for building with concrete flat roofs shall be heavy duty PVC downpipes including all fixing accessories on external walls.
3. Downspouts for shelters shall be pre-coated galvanized sheet metal to ASTM A 591 and A 143."