Wall Ties are crucial to the stability and safety of cavity walls yet, of the circa 10 million homes constructed with cavity walls in the UK, a Building Research Establishment (BRE) report indicates that 2 million of these are experiencing wall tie corrosion or failure.
This is largely due to decades of building cavity walls with mild steel wall ties which deteriorate and eventually fail over time, especially if improperly installed. If too many wall ties corrode, walls can become unstable and partial or total collapse of the wall is possible.
These days, improvements in materials including use of stainless steel and plastics have generated better results however the issue of the complicated and time consuming installation processes remains and no matter how skilful and experienced the installer is, there is still a risk of future wall tie failure.
In the event of wall tie failure, remedial wall ties can be installed. Traditional remedial wall ties are made from metal or plastic and although usually labelled with a lifespan of 15-50 years, they are time consuming to install and are subject to the same failure risks as the initially installed wall ties.
The Holdfast remedial wall tie is made from a glass reinforced engineering polymer and is completely corrosion free giving it a life expectancy in the region of 100 years. We have recently completed a 10 year test programme and are able to report pull test results of over double the recommended force needed to ensure the wall ties are effective. Although they cost around the same as other wall ties on the market, no special equipment or materials are needed for installation and the time taken to install them is 80% less than traditional alternatives.
Traditional Wall Tie installation process – estimate 2.5 days per average house
- First a hole is drilled in the outer leaf of the bricks (not the motor bed)
- Continue drilling into the inner leaf to a preset depth
- Blow out dust from the hole
- Fill the inner hole with an epoxy resin using an extension tube fitted to a cartridge gun
- Place the wall tie into the resin and wait for a short while until the resin has ‘gone off’ slightly
- Fill outer hole with brick colour resin and remove excess resin
- Do this 200-250 times (average semi-detached house) This is known as a resin/resin fix.
The Holdfast wall tie has been developed to slash installation time and effort by up to 80%.
Holdfast wall tie installation process – estimate 2 hours per average house
- Drill a hole in the same manner as if using traditional remedial methods
- Insert the wall tie into the hole
- The centre pin is then hit with a rubber hammer and the pin is sent home to open both ends of the tie at the same time
- The hole is then filled with a colour matched mortal. No resin, no waiting around.
Check out our video to see how simple they are to install