Other Forms of Barrel Vault ~ by cutting intersecting and placing
at different levels the basic barrel vault roof can be formed into a
groin or northlight barrel vault roof:-Conoids ~ these are double curvative shell roofs which can be
considered as an alternative to barrel vaults. Spans up to 12„000
with chord lengths up to 24„000 are possible. Typical chord to
span ratio 2:1.Shell Roof Construction