fabric definition, kangaroo, grasshopper

i already made a definition which allows me to have a fabric falling between two buildings in order to have a deformation .. although i have an issue the fabric its to loose , i want my fabric to be able to fall but to maintain some of its plasticity in order to have some thresholds with in it ... can you help me??

my goal is to create something similar as the rood bellow but the anchor point will be some buildings roof and this will fall in between .. please help...