What is the best sealant for fiberglass steps to surrounding concrete?

[cozybuilder]

I need to reseal my fiberglass step insert to the surrounding concrete. What is the best sealant to use for this job?

Thanks,

Philip

 

[cowboycasey]

I am not sure if there is a specific product used by pool builders to do this, if there is please let us know

I would use 3m 5200, "3M 5200 is a single part sealant that cures to form a firm, rubbery waterproof seal. When fully cured, this high strength marine adhesive remains flexible and suitable for use where shock, vibration, shrinking or swelling are concerns."
3M 5200 Marine Sealant

It is permanent, so make sure you don't ever want it to come off

 

[cozybuilder]

Thanks, cowboycasey.

That is some serious looking stuff! I'll see what I can find out from pool builders and will report back here.

Philip

 

[cozybuilder]

Thanks, cowboycasey.

That is some serious looking stuff! I'll see what I can find out from pool builders and will report back here.

Philip

A pool builder I contacted recommended filling any voids with play sand up to a half-inch from the top, then filling this half-inch void with self leveling concrete sealant available from Home Depot.

I'll give this method a try and report back here when finished.

Philip

 

[pookiesunshine]

A pool builder I contacted recommended filling any voids with play sand up to a half-inch from the top, then filling this half-inch void with self leveling concrete sealant available from Home Depot.

I'll give this method a try and report back here when finished.

Philip

This must be a top, horizontal seam then. I was thinking it might be between the bottom of the coping and top of the steps which would require something different from self leveling.

 

[cozybuilder]

This must be a top, horizontal seam then. I was thinking it might be between the bottom of the coping and top of the steps which would require something different from self leveling.

You're exactly right, pookiesunshine. I'm referring to the top, horizontal outside seam where the outside perimeter (3 sides) of the step insert joins the surrounding concrete.

I'll post some before and after photos.

I do recall this same builder used silicone sealant to seal the underwater vertical seam where the step insert joins 3 pieces of trim that separate the step insert from the vinyl liner.

Philip

- - - Updated - - -

I do recall this same builder used silicone sealant to seal the underwater vertical seam where the step insert joins 3 pieces of trim that separate the step insert from the vinyl liner.

Philip

To clarify, vertical seam as in on the wall of the pool. Technically, at the step insert, there are 2 vertical (up and down) seams, and one horizontal (side to side) seam on the vertical pool wall.

Philip

 

[pooldv]

That sounds like an expansion joint and it should be filled with sand and/or foam backer rod to about 3/8-1/2" depth. Then the joint should be filled with self leveling polyurethane caulk. My PB uses Sikaflex brand.

 

[cozybuilder]

That sounds like an expansion joint and it should be filled with sand and/or foam backer rod to about 3/8-1/2" depth. Then the joint should be filled with self leveling polyurethane caulk. My PB uses Sikaflex brand.

Hi pooldv,

This is a tardy follow up, but that is basically what I did. After removing what was left of the old sealant, I filled the void between the step insert and the concrete with sand (this seam varied in width and depth, and there was no expansion joint material that I could see). I then used a toothbrush to achieve the correct depth with the sand. Sikaflex brand is the one I used. It is self-leveling and for use in horizontal joints only, but I experimented with this stuff and found that by holding the nozzle against the steps during application, it worked great. The stuff exits the tube in a semi-liquid state and sticks where it is applied, but after a minute or two, it goes into a more liquid state and the "self-leveling" feature really kicks in. This created a really nice cove joint between the vertical pool step and the horizontal concrete.

I stuck around to watch the stuff do its magic. I had some low spots develop where more material was needed; adding more material was easy to do because nothing had set up yet. I was also able to clean up any mistakes and some overflow by wiping it up with paper towels before it started setting up.

Thanks everyone for the input!

Philip

 

[slickraft]

I use Sikaflex too in all kinds of horizontal seams like concrete driveways and patios. I go so far as to wait until winter when the gaps are the widest due to the cold. As mentioned by others, I fill with sand or backer foam first and then apply and let it level. Come summer, when the concrete expands, it compresses a little but I keep it thin enough so that is not an issue. If I seal in the summer, the shrinking concrete in the winter tends to pull the caulk apart in a season or two.

 

[pooldv]

Hi pooldv,

This is a tardy follow up, but that is basically what I did. After removing what was left of the old sealant, I filled the void between the step insert and the concrete with sand (this seam varied in width and depth, and there was no expansion joint material that I could see). I then used a toothbrush to achieve the correct depth with the sand. Sikaflex brand is the one I used. It is self-leveling and for use in horizontal joints only, but I experimented with this stuff and found that by holding the nozzle against the steps during application, it worked great. The stuff exits the tube in a semi-liquid state and sticks where it is applied, but after a minute or two, it goes into a more liquid state and the "self-leveling" feature really kicks in. This created a really nice cove joint between the vertical pool step and the horizontal concrete.

I stuck around to watch the stuff do its magic. I had some low spots develop where more material was needed; adding more material was easy to do because nothing had set up yet. I was also able to clean up any mistakes and some overflow by wiping it up with paper towels before it started setting up.

Thanks everyone for the input!

Philip

Nice work! Looks great. Thanks for following up.