What happens if a sealant backer is not used?

When a sealant backer is not used, the primary consequence is that the sealant will have a shallow depth. The backer serves multiple purposes, one of which is to control the depth of the sealant bead. Without it, there is a risk that the sealant will not achieve the proper depth required for effective adhesion and performance, which can compromise the sealant's ability to form a strong bond and maintain its intended function.

Sealant materials are formulated to work effectively within certain parameters, including depth. If the bead is too shallow, it can lead to inadequate sealing against moisture, air infiltration, or other environmental factors. This can ultimately result in potential failures of the sealant over time, reducing its lifespan and effectiveness in preventing unwanted elements from penetrating joints and gaps.

Using a backer ensures that the material can properly stretch and compress in response to temperature changes and structural movement, enhancing overall performance. Consequently, this question centers on the critical role a backer plays in ensuring a deep and effective seal, which is paramount in glazing applications.