HOUSE prices could drop by up to 5% if the industrialised building system (IBS) is made mandatory in construction in 2020, said the Construction and Industry Development Board (CIDB).

Its chief executive officer, Ahmad Asri Abd Hamid, said developers would be able to reduce cost in terms of manpower as well as productivity, whereby the project duration could be cut to by 12 to 18 months with IBS compared with conventional construction method.