Hex Head Tek Screws - Which Ones Do I Need?

These tek screws are commonly used in the roofing industry for fixings roofing sheets and cladding to metal substrates. They can also be used for light duty metal to metal fixing. The drill point on these will drill through 3.5mm steel, and it is important that you do not use these for anything thicker than 3.5mm. Doing so will make the threads tap into the substrate before the drill point has gone through, and it will cause the screws to snap. The coarse thread also works well for fixing into plastics. A 16mm EPDM washer is supplied with each screw, and it provides a water tight fixture for use in roofing applications.

These tek screws are also mainly used in the roofing industry, but they are for fixing into much heavier duty steel such as steel i-beams. The drill point on our heavy section tek screws will self-drill through up to 12.5mm steel. Although technically these are OK to use for thin gauge steel also, it is generally recommended that these are not used on anything less than 4mm thick, because the fine thread is designed to tap into much thicker steel and may not bite particularly well. A 16mm EPDM washer is supplied with each screw, and it provides a water tight fixture for use in roofing applications.

SUPERTEK tek screws are a very heavy duty Tek screw for self-drilling through up to 35mm thick steel. There are three different options for SUPERTEK screws - TEK-7, TEK-8 & TEK-10. TEK-7 screws will self-drill though 4.0 - 18mm steel, TEK-8 screws will drill through 4.0 - 22mm steel & TEK-10 screws will drill though 4.0mm - 35mm steel. Although technically you would be able to use these screws on thinner steel, it is not advised as the thread pattern is specifically designed for thicker steel and so will not be effective in thin gauge steel. Our range of SUPERTEK screws is not stocked with EPDM washers as standard, but you can fit the 16mm or 19mm EPDM washers to all the sizes, and we sell the washers separately. 

Gash point tek screws are specifically for fixing thin gauge roofing panels to timber. Rather than a drill point, these screws have a ‘gash point’, sometimes also described as a ‘type 17 slash point’ which will self-drill through very thing gauge metals and plastics. The slash point allows these tek screws to bite into timber much better than standard tek screws. A 16mm EPDM washer is supplied with each screw, and it provides a water tight fixture for use in roofing applications.

Stitching tek screws are specifically for fixing thin gauge metals together. The drill point on stitching screws is shorter than on light duty tek screws, and the thread is coarser and wider to get a better hold in thin gauge metals. Typically, stitching screws are 6.3mm diameter (equivalent to 14g), whereas standard tek screws are 5.5mm (equivalent to 12g). A 16mm EPDM washer is supplied with each screw, and it provides a water tight fixture for use in roofing applications.

Hex head tek screws to DIN 7504K are essentially the same as light section hex head tek screws, however they do not come with a 16mm EPDM washer and are available in a wider range of diameters. These tek screws are intended for more universal use and are not specifically made for the roofing industry. The maximum material thickness varies depending on which diameter you use (please refer to the product detail pages on our website), but they are a ‘light duty’ tek screws and as such should not be used with any metals thicker than 3mm. These tek screws can be used with wood, plastic and metals.