Like Sealux and Panseal profiles, the inner surface of the Cladseal strip outer leg is laminated with a sealant bond-breaker tape (green line)
Excluding the uppermost surface (x), the inner cavity walls of Cladseal are partially layered with a polythene tape indicated by the green line. Sealux-N silicone will not bond to this polythene tape. It is a silicone bond breaker !
When joint movement occurs between the wall and ledge, the Sealux-N silicone bonded to Cladseal at (x) and to the ledge at (y) comes under tension.
To reduce this build up of tension the silicone must stretch, but to stretch without restriction (like an elastic band), it must first release off the inner cavity walls of the Cladseal profile. The silicone bond breaker allows the silicone to release off the inner cavity walls and stretch to reduce the build up of tension.