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Concrete Stair—a restoration after 21 years & about 5 hurricanes |
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2026-06 A little restoration after 21 years and about 5 hurricanes . . .
After all these years the stair has really held up pretty well. Hurricane Milton in 2024 came up Tampa Bay at that exact angle to bring that dreaded Storm Surge. There were only two other hurricanes in recorded history that came in and caused a storm surge like this. One in 1948 which was not quite as bad, & one in 1921 which I believe was worse than Milton in 2024. I’ve heard some old-timers talk about that storm of 1921 . . . A guy who worked at the old Tyson Bolt on Adamo said there was a painted mark on one of the old wood power poles by the warehouse that was about 21’ or26’ (I can’t remember which) above the ground that marked the waterline from that storm!
The owner of this property with the stair said that the water came up about 5’ above the driveway and sat there for about 3 days! Now, all of the rebar in the stair was epoxy coated just as I specified but after sitting under 5’ of saltwater for 3 days I’m not surprised that some of it found its way into any little scratch in that epoxy coating and finally showed through in the way of hairline cracks, mostly in the landing and the lower steps. The worst case was at the west end of the lowest step where a chunk of the concrete had almost completely separated. Surprisingly, the rebar was still mostly epoxy coated and we could see a small area on one piece that had a layer of rust . . . Likely the culprit for expanding and popping the concrete.
We not only design & build, but are always looking to make things better, and in a better way, and to last longer. So when we have a chance to take a look at the longevity of one of our projects, first it’s a learning experience for us, and it’s a plus for the owner that we can come in and make repairs and do a restoration that is exactly in line with the original intent of the project . . . in function, theory, composition, and durability. |
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Above: Track of SWFL3 1948
Below: Stock footage of Milton 2024 |
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Above: Track of Milton 2024
Below: Track of SWFL3 1921 |
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The repair plan was to chip off the loose pieces of that one lower step, wire brush all the rebar we could, treat the exposed bars with a phosphoric acid solution that turns iron oxide into iron phosphate, then epoxy coat everything on the broken off surfaces using the thick, paste 4500 and epoxy the pieces back in place. Then, for the cracks, we use an epoxy injection system where you epoxy these plastic injection ports onto the crack spaced about 9” o.c. using a thick epoxy paste and cover/seal the length of the cracks above and below. Then you use a low viscosity epoxy—which are pretty much all made to be mixed at a 2:1 ratio, which of course requires a “special dispensing gun” . . . But I found out that it’s just a dual gun(which I had) with a smaller diameter plunger disc which I was able to machine from a bronze rod on my lathe . . . —and inject the cracks from the ports working your way from one end to the other of the crack until it’s filled. You can see when it’s filled because it will start to come up in the next port—that’s when you know to cap that port & move to the next one.
When the injecting is done and allowed to cure overnight you come back & chip off the ports & grind the epoxy down flat & smooth using a diamond grinding wheel on a 4.5” grinder, then we use a zirconium sanding disc on the grinder to go over the whole thing before applying a coat of SiakTop 123 Plus and giving it a fresh steel trowel finish. It ends up looking just as it did when it was first completed . . . And hopefully sealed up better for the next hurricane & storm surge. |
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These are screenshots of a couple storm surge models, the lower one was during Helene, just weeks before Milton in 2024. The above model shows about 16’ above sea level, the lower showing only about 7ft above sea level. |
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Below: We use SealBoss.com 4500 & 4050 for capping & injecting, but in the event that you run out of the 4500 capping paste, Sika’s Anchoring Adhesive works pretty well too. It’s really thick & sets up in about 5-10 minutes enough to inject. |
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The rebar was epoxy coated . . . |
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The restoration was a success and hopefully gives the stair another decade—or hopefully multiple decades—of life. We’ve been able to take another step in our quest to make more beautiful things in the world in a better way.
The 316L rails still look the same as the day we finished them and now, the concrete structure basically does too again.
Until next time . . .
Cheers!
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