Hundreds of new homes are in danger of crumbling after they were built with sub-standard concrete, a damning investigation has found.
Weak mortar that does not meet the recommended industry standards has been used on at least 13 estates in the UK, leaving the homes at risk of disintegrating.
It is thought the issue could affect thousands of other properties across the country, but developers are forcing desperate homeowners to sign gagging orders in order to claim compensation and save their homes.
In one single estate in the Scottish borders, it is thought that leading housebuilder Taylor Wimpey has agreed to replace the mortar in more than 90 separate properties.
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One of those homes was owned by Vincent Fascione (pictured), 70. He said he was watching football on TV one evening in 2016 when he heard a loud cracking noise from the external walls of his house. The next day he found a sand-like substance all over his front path and driveway
The industry says mortar performance can be affected by a number of factors, including an inadequate sand to cement ratio.
One of those homes was owned by Vincent Fascione, 70. He said he was watching TV in 2016 when he heard a loud cracking noise from the external walls of his house.
The next morning, he found a sand-like substance all over his front path and driveway, according to the Victoria Derbyshire show.
Photographs and video from the time appear to show growing cracks in the mortar holding his bricks together.
Mr Fascione, from Coatbridge, near Glasgow, bought his semi-detached property in 2012 for £112,500.
He complained to the homebuilder, Taylor Wimpey, and to the NHBC, the industry body that provides warranties for new-build houses.
Hundreds of new homes are in danger of crumbling after they were built with sub-standard concrete, an investigation has found. There are reports of properties with weak mortar that does not meet recommended industry standards on at least 13 estates in the UK
In one single estate in the Scottish borders, it is thought Taylor Wimpey has agreed to replace the mortar in more than 90 separate properties. The homebuilder says an assessment by engineers found ‘no structural issues’ with the homes
Under NHBC guidelines, mortar in most areas of the UK should be made of one part cement to 5.5 parts sand.
In severe weather areas such as Coatbridge, there should be even more cement in the mix to make it stronger and more durable.
Laboratory tests on samples taken from parts of Mr Fascione’s home showed the amount of sand was almost three times higher than recommended.
Some homeowners have been asked to sign gagging orders to claim compensation, making it difficult to assess the scale of the problem, the Victoria Derbyshire show on BBC2 reported
Mr Fascione said: ‘I’ll never buy a new-build house again. It’s just been disastrous for me.’
The Victoria Derbyshire Programme said it had heard about new-build properties in at least 13 estates from Scotland to Sussex, built by different companies, with what appears to be a similar problem.
Referring to one single estate in the Scottish borders, the homebuilder said an assessment by engineers found ‘no structural issues’ with the homes.
Phil Waller, a retired construction manager, said: ‘This is both widespread and serious. It cannot be explained away by the industry as a few isolated cases.’
Some construction experts also blame the switch to a new type of factory-mixed mortar, which might pass a different strength test in the laboratory but not always be strong enough in the real world.
In some cases, customers have ultimately had their houses bought back by either the homebuilder or the NHBC.
In others, it appears repairs have been made and compensation paid as part of a deal that involves the signing of a non-disclosure agreement or gagging clause.
An NHBC spokesman said it included a confidentiality clause in a ‘small number of rare circumstances’ but declined to disclose the number.
Some construction experts also blame the switch to a new type of factory-mixed mortar, which might pass a different strength test in the laboratory but not always be strong enough in the real world
He added: ‘We work with builders to help them improve the construction quality of the homes they build. However, it is the builder who is ultimately responsible for the quality of the new homes they build.’
A Taylor Wimpey spokesperson said: ‘Quality assurance tests are carried out on the mortar used on all of our sites and there are very few instances where it fails to meet the required standards.
‘The mortar we use in the construction of our homes complies with building regulations and is of sufficient strength to meet the structural requirements of the houses and garages.
‘We want to reassure our customers of our absolute commitment to delivering excellent quality homes and achieving high levels of customer satisfaction.
‘On the rare occasions where issues do arise, we endeavour to resolve them as soon as practically possible.’