Hundreds of new properties have been built using weak mortar that does not meet recommended industry standards, the Victoria Derbyshire show has found.
There are reports of homes with the fault on at least 13 estates in the UK.
The full extent of the industry-wide problem is hard to measure as some homeowners have been asked to sign gagging orders to claim compensation.
The industry says mortar performance is a complex issue and can be affected by a number of factors.
One of those homes was owned by Vincent Fascione, 70. He says he was watching football on TV one evening in 2016 when he heard a loud cracking noise from the external walls of his house.