If your walls are starting to show signs of cracking and/or bulging, there could be an issue with the cavity wall ties, and they may need to be replaced. While an inspection from a specialist company can help identify the cause of the issue, it can be helpful to know a bit about cavity wall ties yourself, and firstly, to know whether your home even has them.
If you’re not sure whether your home has cavity wall ties, there is a simple way to check. Have a quick look at the way the bricks of your home have been placed, and that should tell you right away. If the bricks have been laid along their length the full width of the wall, this would strongly suggest that your home has cavity walls. Should the bricks be laid in such a way that they’ve been placed lengthways alongside another brick that has been laid widthways, this would indicate that your home doesn’t have cavity walls, and that they are instead, solid.
Let’s take a look at exactly what cavity wall ties are:
Cavity wall ties explained
Typically made out of metal that has been coated in zinc or bitumen, cavity wall ties were introduced to the construction industry back in the early twentieth century, and are used to hold two parts of a wall together to form what is known as a ‘cavity wall system.’
When buildings are constructed in this manner, they are afforded a higher degree of protection from environmental factors externally, and help limit the amount of heat a property will lose, too. Unfortunately, cavity wall ties don’t last forever, and if they begin to deteriorate without any action being taken to replace them, they can lead to structural repairs that are typically very costly.
What are some of the causes of wall tie failure?
There are two main causes of wall tie damage, and these are as follows:
- Corrosion
When carbonation causes the mortar beds between the brick ties to undergo a chemical change, the mortar will go on to attack the walls, which in turn causes iron oxide, or rust, to build up. if left untreated, the rust will force the mortar beds to separate, manifesting itself in cracked brickwork, which will be visible to both the naked, and the untrained eye.
- Improper installation
If the wall ties in your cavity wall weren’t installed correctly at the time of construction, this can cause issues with the ties later on in life, and they may need replacing. It’s possible that someone who isn’t a wall tie specialist installed the ties in your home, and either didn’t use ties of an appropriate length, or didn’t space them out correctly.
How are wall ties repaired and replaced?
If your walls are cracked, a wall tie specialist will use equipment specially designed for the purpose – such as fibre optic borescopes, low impact drills and metal detectors – to detect and replace any failing or damaged wall ties within the cavities of your walls. And all while causing minimum disruption to your home or your schedule.
If a specialist has determined that your home has been constructed using cavity wall ties, and a survey has shown some of them to be faulty or damaged, they will go on to use remedial wall ties to reconnect the interior and exterior walls of the cavity structure already in existence. This action will protect the structural integrity of your home, and save you a lot of money, and potential heartache, further down the line.