The Bond Beam Tie Down strap from Pryda Australia has been designed to assist builders in quickly tying down roof and floor trusses to masonry blocks. The Bond Beam Tie Down strap offers a safer, more cost-effective alternative to the current method of tying the trusses to masonry block walls with cleats, bolts and nuts.
Using the current method, once the builder has measured up and marked the truss location, the cleats need to be threaded along the reinforcement rod and into position. The block walls are then filled. When the trusses are delivered to site, they are erected and tied down to the block wall by drilling through the truss and fixing the appropriate nut and bolt through the cleat and truss.
This method extends the truss installation time and adds significant cost in cleats, bolts and nuts. It also presents some safety issues when drilling through the nailplate on the truss. Sometimes the drill can kick back and throw the installer off balance.
The Bond Beam Tie Down strap comes pre-bent with the plastic stabilisers pre-installed. These stabilisers are located to provide a maximum 50mm top cover to reinforcement bars.
Once the builder has measured up and marked the truss location, the Bond Beam Tie Down straps are simply located into position. The plastic stabilisers help keep the strap stable and at the correct orientation, until the reinforcement rod is placed and bond beam fully grouted. Alternatively, if the reinforcement rods are already in place, the Bond Beam Tie Down strap can easily be threaded underneath the rods and into position.
When trusses are ready to be installed, the Bond Beam Tie Down straps need to be folded over the top of the truss and nailed with 32 x 2.3mm screw hardened pneumatic nails. Three nails on the far face through strap folded over chord, one nail on top and one on the near face.
When developing the Bond Beam Tie Down strap Pryda were careful to ensure that it complied with all the relevant authorities. The Bond Beam Tie Down strap’s dimensions are 880 x 32 x 1.2mm and it is manufactured using G300 steel coated to the equivalent of Z600 grade. Australian Standards AS2699.2, dictate that any tie down product that is built into masonry must be manufactured from steel that has a galvanized coating of at least grade Z600.