Cavity walls incorporating metal ties have been in use since the beginning of the 19th century, but it was the 1930’s building boom that produced large numbers of cavity construction dwellings. From 1945 cavity wall construction became the normal for houses and many other buildings.
The early metal ties produced mainly from wrought or cast iron performed satisfactorily, but in more recent years mild steel ties have been used and despite galvanising or bitumastic treatments have been found to suffer from corrosion.It must be stressed that wall tie failure, or cracking of the outer leaf of a domestic property, is rarely an immediate threat to the safety of the occupants. The risk is greater to pedestrians and adjacent property therefore measures must be taken to restrict access to the risk areas if severe wall tie failure is diagnosed. Horizontal cracking at regular intervals. Normally every five to seven courses and frequently evidenced by re-pointing, resulting in wide joints. The metal detector will confirm the presence of wall ties along these joints.
Outward bulging of brickwork may indicate wall tie corrosion. The inner leaf of the wall being more firmly tied into the construction is less likely to move, with the rust lamination of the wall ties, than he outer leaf. This outer leaf may lift at the horizontal cracks, and/or be forced outwards. We offer a range of wall designs from resin ties, auto torque mechanical ties.
Replacement ties are available in various lengths to suit all cavity widths. The replacement ties incorporate a centre drip to prevent transmission of water across the cavity. On completion of work a wall tie guarantee is available.
Contact us to arrange a free no obligation survey on01792 897 142.