Check out this video that Mark Nunn and I made (I will admit, it needs some editing… for a quick reference check out 1:25 and 2:45) installing UL System CAJ8022 using STI’s SpecSeal Self Leveling SIL Silicone Firestop Sealant.

STI’s self-leveling product is great because there is no tooling required… it will find the low spot so make sure to pack that mineral wool tight… this means that you will never have to remove another riser clamp or risk getting your hand caught trying to caulk in the back corner.

Some of the benefits to using silicone:

• Low modulus – allows up to ± 50% movement capability.
• Auto-bonding – allows fresh sealant to adhere to cured sealant.
• Excellent water-resistance – for water-tight sealing.
• Ozone and UV-resistant – for excellent weathering ability and long service life.
• Excellent chemical resistance – best choice in polluted or corrosive atmospheres.
• Excellent adhesion to most building substrates (primerless adhesion).
• UL tested for W ratings.
• Acoustically tested – reduces noise transmission

Some typical applications:

• Through penetrations and joints.
• High temperatures or movement.
• Electrical, data, or telephone cables.
• Slab Edge/Curtain wall, safing and construction gaps.
• Seismic and expansion joints.
• Top-of-wall joints.
• Single or multiple metallic pipes, conduits & tubing.