S-5-H™ Clamp

The answer to this question varies with the load direction, the seam profile, the roof material and the clamp model.

These variables result with a wide range of holding capacities from ±300 lbs (235 kg) to ±4,000 lbs (1800 kg). This is why for critical applications it is important to correctly identify the roof panel, seam type, gauge, etc along with the recommended seam clamp for the specific roof.  [ link-- Clamp-to-seam tool]  When used on some “applied cap” architectural type seam styles, S-5! may yield low load-to-failure results as compared with integrated seam profiles. Always check our load table to verify the correct allowable holding strength on your specific roof type. Read more about our testing.

The setscrews, which make a small dimple in the panel seam, optimizing holding strength, are normally tensioned to 115 inch-pounds for test purposes. This is because the tools normal to the trade are rated at this tightening torque. But there are some exceptions to this rule. On some profiles and gauges in steel, screw tension of 115 inch-pounds will not adequately dimple the panel seam. For this reason, some tests are run with higher screw tensions on profiles with increased gauge or thickness.

The appropriate setscrew tension is always published on installation instructions for every clamp. When the tested torque is 115 in. lbs. the recommended installation torque instructs a window between 130 to 150 in. lbs. to be sure the tested torque is reached. When test torque is higher, the corresponding window is also higher.

For horizontal seams with .5″ (13 mm) or less dimension of folded portion:

• Option 1: Crimp the seam to 180 degrees at the desired clamp location and use the S-5-E (or Mini). This is easily done with a hand seaming tool with no harm to the seam and actually strengthens the seam.
• Option 2: Use the S-5-T or the S-5-S to avoid altering the seam.

For horizontal seams greater than .5″ (13 mm) and less than .625″ (16 mm) dimension of folded portion: Use the S-5-T.

For horizontal seams greater than .65″ (16 mm)

• Option 1: Use the S-5-U in its horizontal orientation or the S-5-H90. (Setscrews are tensioned top-down attack).
• Option 2: For horizontal seams greater than .65″ (16 mm) but less than .80″ (20 mm) use the S-5-H. (setscrews are tensioned side-attack).

For horizontal seams less than .65″ you may also crimp the seam as shown above for the S-5-E.

Read more.

All S-5! clamps undergo rigorous mechanical tensile load testing. We typically test in two load directions: Negative load normal-to-seam testing (pulling-up), and parallel-to-seam testing (drag load). We actually developed these test protocols back in 1992 as ASTM has no prescribed test procedures for this type of testing. For more on our testing protocols and results, visit this link and check out our video.