Do My Wall Ties Need Replaced?
Do my wall ties really need to be replaced? this is a very common question that we get asked regularly, the honest answer is, it depends on a few different factors. The main issues with existing cavity wall ties is the material that they were made with, prior to 1980 cavity wall ties were normally made from mild steel. Generally houses built between 1920s -1950s had mild steel fishtail ties, and houses built between 1960 to 1980 had mild steel butterfly ties.
When houses from these periods were built using mild steel cavity wall ties, the ties were expected to last the lifespan of the property, but unfortunatley these types of wall ties were susceptible to corrosion, in some extreme cases they have lasted less than 20 years.
Often the first time people come across issues with cavity wall ties is when they are either buying or selling a property, surveyors have collected data over the years and they know which areas of the North East housing stock are more susceptible to having cavity wall tie failure. These areas flag up on their systems prior to them carrying out homebuyer surveys, you will often see a paragraph in your homebuyers report saying somethjing along the lines of “we reccomend that you instruct a reputable wall tie contractor with regard to further investigation of the condition of cavity wall ties”.
We get calls every week from potential house purchasers being asked by their surveyor to get the wall ties checked, almost everyday our surveyors are on the road carrying out surveys for cavity wall ties in the North East.
How do I know if my wall ties have failed?
1. Stepped cracking in mortar beds of brickwork.
2. Bulging brickwork, where brickwork runs out of level.
3. Horizontal cracking of mortar beds, often seen on rendered walls with cracking every 5-7 brick courses apart.
4. Extreme cases can cause lifting of eaves tiles on gable ends due to the expansion of brick course due to the corrroded wall ties expanding.