Easy to apply and quick to set, this caulk is a popular choice for sealing small openings in fire-resistant walls and floors. It’s often used to line seams or fill gaps around cables or pipes that run between rooms. You can use it alone or with other fire-stop products. This caulk is tested to ASTM and UL standards for stopping the spread of smoke and flames. It resists vibration, so it will flex with movement rather than crack or pull away from surfaces. Apply with a caulk gun or trowel.

Spray-on caulk is used to evenly coat hard-to-reach openings. It’s often used to seal the spaces where fire-rated walls, floors, and ceilings meet.

Acrylic caulk is water-based, which is the most common formula for fire-stop caulk. It’s a good choice for most applications. Expandable caulk is used to seal the area around PVC pipes, cables, and other equipment that can melt or shrink during a fire. When it’s heated, it expands to fill gaps.

Silicone caulk forms a watertight, flexible seal. Use it to seal openings that are exposed to weather, washdowns, or standing water.