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Detached Front Steps - Client wants to seal to prevent further separation - Backer rod & sealant 2

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Struct_Dre

Structural
Mar 29, 2019
48
Hello All [bigsmile]

Please see the attached photo of the concrete steps separated from the building. The client wants to seal the opening to prevent further separation and to also prevent water and debris from getting into the space. I believe they should be able to use backer rod and then a sealant on top of the backer rod, but I'm worried that the backer rod may not stay in place and will eventually fall deeper into the crack. Filling with grout seems excessive and difficult to do in this scenario b/c it is such a small space that it would be difficult to get tools or anything in it.

Does anyone have a better remedy for this detached stair? If so, I would be appreciative!
 
 https://files.engineering.com/getfile.aspx?folder=ab548a42-d4a7-4095-ac59-480b00e0c905&file=IMG_6815.JPG
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The backer rod is really only needed for installation of the sealant, once the sealant has cured the bond to the surfaces should keep it in place (if there is no bond it is not sealed).

This won't necessarily prevent further movement though if settlement continues (which is probably exacerbated by moisture issues, i.e. downspout right next to stair).

Struct Dre said:
Does anyone have a better remedy for this detached stair? If so, I would be appreciative!
Remove and replace.
 
Agree with comment above, the downspout needs to be modified to divert water away from the house to prevent further settlement.
 
Struct_Dre:
That’s one hell of a crack/joint to be filled with some (a few) backer rods and caulking, they usually aren’t intended for joints several inches deep and wide. What’s behind the steps, in the way of bldg. foundation? The slab in front of the steps is part of the same mass of conc., right? You should probably understand better, why the conc. steps are settling vert. and rotating around their lower corner near the bldg. This hasn’t happened over night, but that’s what appears to be happening, and some caulking won’t stop it. The downspout is a problem which should be corrected, and what is the checkered pl. and block of wood alongside the near side of the steps. How it its function affecting the steps movement? Once you understand some of these questions, you might come up with a better solution than just some caulking.

 
Anything you do to those stairs won't guarantee future movement. And the gap seems to be too wide for backer rod and and sealant. Max I've ever seen in the vertical is 1.75". So what to do? If this were my industrial building, I'd fill the void with grout, and monitor. If it kept moving, I'd replace it. If this were my apartment complex, and tenants would be using it, I'd replace the stairs.
 
This is a common condition that many slab leveling and foundation underpinning specialty contractors claim that they can fix. I think their methods involve injecting grout or urethane foam under the stairs (I don't think they would use helical piles for this application) to lift the stairs. I have never seen the procedure or results first hand, so I do not know if it is really a viable option, but I know that many of these contractors advertise for this condition specifically.
 
If it is my property, I'll simply ensure the proper slope and extend the downspout a few feet away from the wall; then inject expandable foam obtained from Home-Depot, and observe what happens after at least through one cycle of freeze & throw, and a raining season. Then decide whether to replace it or not. This is just too small a piece to involve specialty contractor for cost concern. But, yes, if this is a rental property, I'll replace it immediately.
 
Sealant application to prevent further movement? Absurd. Find the reason for the movement and fix it. Sealant won't fix it.
 
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