The use of existing nails and screws for fixing fibre cement board (FCB) to timber and steel frames is problematic.
Option 1: When fixing to timber frames clouts are used. This can, and frequently does, result in damage to the FCB through splitting, cracking and/or delaminating of the board. If not immediately evident during installation, this damage becomes apparent as the effects of natural weathering cause the timber and FCB to expand and contract. The resultant damage to the board is not only unsightly, but in time may cause the board to break away from the timber substrate and fall, posing a risk of harm to anyone underneath, especially in ceiling applications.
Option 2: When fixing FCB to steel frames timber battens are sometimes fixed to the steel frames to allow the FCB to then be attached using conventional clouts, but this method has similar problems as when fixing to timber frames.
Option 3: Another method that is widely used when fixing the FCB directly to steel frames is the use of countersunk rib head screws, however this can be just as problematic as the abovementioned options. Screws provide an additional challenge in that the material exhausted from the hole created by the screw, particularly when the screw head embeds itself into the surface of the board, causes a “mushrooming” or “volcanoing” effect around the circumference of the screw head. Subsequently remedial action such as sanding back is required to remove the exhausted material.
Using loose screws also is reasonably fiddly as two hands are needed to position the screw onto the driver tip whilst endeavouring to keep the FCB in place with a “third hand” and failing that, a second person is needed.
These problems weaken the boards’ structural integrity, resulting in repair work by the tradesperson, or in the worst case replacing of the board.
So what is the solution?
The innovative, and patented GrubMates® system overcomes these problems; saving time, labour and replacement material costs. GrubMates® is so named as it is effectively a screw with no head, or an exceedingly small head.
IDEAL Fasteners GrubMates® screws allow steel frame builders to avoid the use of timber battens and clouts. Steel angles or battens can now be used without the problems experienced when using countersunk rib head screws nor unsightly low profile screw heads.
• Mushrooming is eliminated as the GrubMates® screw head finishes flush with or below the surface of the FCB if required.
• GrubMates® do not cause splitting, cracking nor de-laminating of the FCB and its structural integrity is maintained.
• The withdrawal strength of GrubMates® is superior to, the strip torque is up to 220% higher than, and the shear strength is 63 per cent higher than, that of conventional screws when tested in 0.42mm, 0.48mm and 0.75mm steel.
• Significantly the force required to pull the FCB over the head of the GrubMates® screw is 28 per cent and 23 per cent respectively higher than that of the conventional screw and clouts.
The GrubMates® system is used in conjunction with a collation tool that has been specially developed for use with collated GrubMates® screws. Driving the collated GrubMates® screws can be completed with a one-handed operation thereby leaving the second hand free to position and hold the FCB in place during installation.
The GrubMates® tool ensures fast and easy installations and features a specially designed depth set stop to suit collated strips of 50 GrubMates® screws. The kit includes an adaptor to suit Makita corded and cordless tools, an extension shaft for overhead applications, a handle, a driver bit and a second depth set stop which quickly converts the tool to allow for it to be used with collated drywall, chipboard etc., screws.
GrubMates® were originally developed to overcome the problems with the fixing of soffit lining boards in steel frame houses and to eliminate the need for timber battens. Steel Frame builders love the benefits they offer in terms of speed and ease of installation and have found GrubMates® ideally suited for fixing FCB in bracing board and wet area applications.
For further information visit the IDEAL Fasteners website idealfast.com.au or contact your nearest IDEAL Fasteners branch.
