Pools Now Showing Their First Generation of Expansion Joint Failures
Expansion joint sealant is the most consistently underestimated repair category on pools from the 2000s throughout the 19428 area. A concrete crack near the waterline looks like one repair. A section of lifting tile nearby looks like a second repair. The homeowner calls for crack repair and tile repair. What is actually producing both visible findings is the hardened expansion joint behind both of them and a repair that does not address the failed joint produces the same crack and the same lifting tile again within one to two seasons.
PVC sealant applied at pool installation in 2005 has a realistic service expectation of 15 to 20 years. A pool from 2005 in Conshohocken, PA is now 21 years past installation at or past that threshold. As that sealant ages past its expectation and loses flexibility, it stops absorbing the seasonal expansion and contraction between concrete sections. That unabsorbed movement goes into the adjacent concrete as a crack at the joint location and into the adjacent tile bond coat as progressive weakening of the adhesive connection between the tile and the shell. Both findings appear visible at approximately the same time because both were produced by the same underlying cause on the same schedule.