Nine in ten SME housebuilders have warned that the upcoming Building Safety Levy will make more sites unviable, according to new research from the Home Builders Federation (HBF) and Quantum Development Finance. HBF is urging the government to pause the introduction of the levy. The research, based on a survey of SME housebuilders across England, also finds that 36% have already delayed, redesigned or cancelled schemes ahead of the introduction of the levy, applying from October 1.