All buildings are impressions and are scaled to 1/72 (20mm) but you could use 15mm or smaller scales to be honest. The buildings are made from plastic card, foam core & coffee strirrers. The brick rubble is budgie grit and foam-core chunks glued and sealed with pva and then painted. The fallen beams are either coffee stirrers or match-sticks I split in random fashion and then set on fire to produce the charred ends. The mesh in the windows is that aluminium car repair mesh from Halfords. The girders are plastic ones from a model shop.The broken pipes are drinking straws. I made the shell strikes in the walls by digging them out of the foam-core with a craft knife and a heated-needle-in-a-cork device. The buildings' walls were coated with pva and sanded prior to painting in a uniform grey. I went for grey to reflect the utter misery of the Stalingrad battle for those involved.
A GUM Department Store
A Volgograd Tractor Factory
A Barrikady Factory
I can recommend Anthony Beevor's book Stalingrad as an excellent history of the battle. My favourite quote is of the Soviet Officer bellowing at German POWs as they marched into captivity:
You see this? You see this! This is what Berlin's going to look like!
Apparently he made it to Berlin and survived the war.