Coping sealant

[Splinters]

New member here and this question is the reason that I joined your forum. I have an inground pool with a concrete deck and coping around the pool edge. There is a 1/2" to 5/8" wide gap between the coping tiles and the deck surface. When the pool was built (16 years ago) this had Styrofoam in it. My pool people came out two years later and mixed a rubber mixture and carefully poured it into the gap all around the pool. Fourteen years later, this rubber has shrunk to the point that it no longer seals this gap.

What is this stuff called? And is this something that I can buy and do myself? Thanks in advance for any help you can give me.

 

[duraleigh]

The styrofoam is called backer rod and you can get it in some diameters at HD/Lowe's More diameters are available if you have a wholesaler who deals with concrete installers.

Placing the backer rod (pull out the old...or as much as you can get) about a 1/2 inch below the surface, you can fill in with a polyurethane caulk. You can get self-leveling or normal. I tried the self leveling and couldn't master it but I am a DIY guy.

It's a hard job to make look nice on a gap that large so you may simply want to hire it done.