Sikaflex polyurethane sealants will bond to more surfaces, particularly porous substrates such as concrete and masonry, without the use of a primer. It is an accepted fact that Sikaflex polyurethane sealants have superior wetting action in achieving a bond to various joint substrates under jobsite conditions.

Joint sealants have to meet various re-quirements depending on function and location of the respective joint. The purpose of joint sealing generally is to: ́ Prevent passage of media (air, water, chemicals, smoke etc.) ́ Provide thermal and sound insulation ́ Enhance the visual appearance of the construction.

Joints are necessary to accommodate movements in the concrete units caused by thermal contractions and expansions as well as exposure to loading conditions. In this article, we explore the properties of sealants, reasons for joint sealant failures and the criteria for selecting sealant to prolong the lifespan of buildings.

In order to help prevent problems like cracking, weeds, and settling from affecting your concrete, it’s important to fill the expansion joints with a flexible non-sag and/or self-leveling caulk. This will provide protection against water and weeds while still allowing the concrete to move as it expands and contracts.

A sealer is soft and able to accommodate the concrete slab's expansion and contraction. The sealer's purpose is to prevent water, ice, and dirt from getting into the joint (and into the subgrade) and to prevent intrusion from below the slab—including of radon.