Researchers developed a new type of cement sheet reinforced with polyolefin films called netcem to control cracks in concrete structures. They tested different forms of netcem and found that those with open network polypropylene film were stronger than those with woven mesh. The composites maintained their strength even after exposure to water and UV radiation. High modulus polyethylene film increased load capacity but had slightly lower failure strain. Fine cracks developed in the cement matrix under load, with closer spacing in composites with more polyolefin. Tests on concrete prisms with netcem panels showed promise in controlling surface cracking.