Sealants & Caulk

Flexible sealants are used at specified movement joints, perimeter joints, changes of plane, and transitions where movement between surfaces or materials must be accommodated. Common locations can include shower corners and floor-to-wall transitions. Joint placement and sealant requirements depend on the tile assembly and applicable installation specifications.

Silicone and polyurethane are different sealant chemistries with different performance characteristics. Silicone is commonly used for flexible, water-resistant joints in kitchens, bathrooms, and showers, while polyurethane products are widely used for compatible construction joints. Adhesion, movement capability, paintability, curing, weather exposure, and substrate compatibility vary by product.

Showers and other wet areas commonly use sealants specifically approved for moisture exposure and the adjoining materials. Compatible silicone sealants are frequently used at designated tile joints, changes of plane, fixtures, and plumbing penetrations. Waterproofing systems can require their own manufacturer-specified sealants for seams, penetrations, or transitions.

The terms caulk and sealant are often used interchangeably, but products can differ significantly in flexibility, movement capability, chemistry, and intended application. Some caulks are intended primarily for filling relatively low-movement gaps, while higher-performance sealants can be formulated to accommodate specified movement, moisture exposure, or demanding construction conditions.

Expanding foam sealant fills compatible gaps, openings, cavities, and penetrations around building components. Common applications can include spaces around windows, doors, pipes, and framing penetrations. Expansion characteristics and approved uses vary, so the product should be selected according to the gap size, surrounding materials, exposure conditions, and application requirements.

Many waterproofing systems use compatible sealants at seams, penetrations, drains, transitions, flashing details, or other connection points. Compatibility is system-specific, however. Use the sealant approved by the waterproofing manufacturer rather than assuming a general-purpose silicone, polyurethane, or construction sealant can be substituted within the waterproofing assembly.

Products specifically approved for exterior use can seal compatible joints around windows, doors, masonry, penetrations, and other building components. Exterior sealants must meet the requirements of the application for moisture, temperature, sunlight, movement, and substrate compatibility. Not every interior caulk or sealant is suitable for outdoor exposure.

Consider the materials being sealed, joint location and dimensions, expected movement, moisture exposure, interior or exterior use, paintability, and cure requirements. For tile and waterproofing assemblies, also verify compatibility with surrounding membranes and setting materials. Select a sealant specifically approved for the intended substrates and service conditions.