DPR visited a property in Doncaster last month where wall ties had failed and caused huge destruction to a property and a car. Thankfully this happened during the night when no-one was around but DPR do believe if someone had been underneath this, it would have been a fatal accident.

How did it happen?

Below Managing Director Darren Rickett C.S.R.T. (Certified Surveyor) explains the technical aspects of the structure and why it failed. He said:

“The walls of many homes in Yorkshire are built using a cavity construction, which means that the inner and outer skins of brickwork are separated by this cavity. The two skins are held together by the insertion of metal wall ties at a set pattern upon original construction.

“All cavity tied properties constructed pre-1981 are prone to cavity wall tie corrosion/failure at some point in their lives.

“This is because of a few reasons – Prior to the 1930s wall ties were not galvanised, meaning no protection against corrosion. Galvanisation standards were also reduced between 1964 and 1981, meaning that millions of substandard wall ties were produced for nearly 17 years. “

What to look for!

Thankfully, there are a few things that will indicate whether you have substandard Wall ties. Darren continues saying: “Typical signs of wall tie failure are horizontal cracking at regular intervals to the external mortar joints typically around windows and doors and also outward bulging of the affected walls. The ties corroding and expanding into the horizontal mortar bed joint into which they are seated cause this.

“One of the main influential factors of corrosion is the presence of black ash mortar, which has high sulphur content which when moisture is present forms mild sulphuric acid, which has very considerable corrosive capabilities.”

He goes on to say: “The visible external effects of wall tie failure will initially begin with fine horizontal cracking of the mortar joint. This is followed by, if neglected, wall bulging and eventual collapse of the outer skin of brickwork. “

The Warning

Building Research Establishment shows that at least 10 million UK properties have the potential or are suffering from wall tie corrosion right now. It is important if you notice any of these signs that you get them solved right away by a roofing specialist.

What DPR will be doing?

In this scenario, the damage has caused great financial loss to the family, including ruining a six month old brand new BMW. DPR is currently rectifying this issue and we will report on how we have completed the repair job in a few weeks time.

DPR urge anyone who notices the signs of this to act before it is too late. If you live in Leeds please do not get caught out like this family and get a professional Leeds roofer and wall tie specialist to check out your home. If you would like more advice, please do not hesitate to contact us on 0113 335 0043.