A flexible foam material, typically cylindrical, is employed to partially fill gaps or joints before applying sealant. This material serves as a backing to control sealant depth and prevent three-sided adhesion, which can compromise the sealant’s performance. It is commonly available at home improvement retailers.
Using this product ensures proper sealant application, improving the lifespan and effectiveness of the seal. Historically, alternatives such as rope or rags were used, but the specialized product provides a more consistent and reliable result. It contributes to energy efficiency by preventing air and water infiltration through gaps in construction.
