Concrete Topping

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Author Message Jerome J. Lazar, RA, CCS, CSI, SCIP Senior Member Username: lazarcitec Post Number: 1393 Registered: 05-2003 Posted on Thursday, June 11, 2015 - 08:01 am:    I have an architect who is telling me that polished concrete is considered a concrete topping, can someone advise on the definition of a concrete topping? Where would one place a spec for Polished Concrete in 50 div format? Dave Metzger Senior Member Username: davemetzger Post Number: 587 Registered: 07-2001 Posted on Thursday, June 11, 2015 - 09:02 am:    Polished concrete is not a topping, although toppings can be polished. When I've specified polished concrete, the polishing operations have been done to a structural slab or slab on grade, so a concrete topping was not involved. However, there is the possibility that construction operations subsequent to the polishing could damage the polished finish; in those cases, a concrete topping could be applied over the slab at a later date and then the topping would be polished. In either case, polishing is a finishing operation, not a topping per se. MasterFormat has assigned Section 033543 Polished Concrete Finishing to this. Liz O'Sullivan Senior Member Username: liz_osullivan Post Number: 185 Registered: 10-2011 Posted on Thursday, June 11, 2015 - 09:26 am:    If you'll have polished concrete, there are a lot of different things to consider as you prepare the Cast-in-Place Concrete section, or as you review it, if Structural prepared it. Mockup requirements for polished concrete have to be carried over into the concrete section - they can't do mockups unless the concrete was mocked up . You may not want to use fibrous reinforcing in slabs to be polished, or consider using only natural fibers (coordinate with Structural). You don't want air entrained slabs if they're to be polished (coordinate with Structural). There are more issues to be prepared for, but that's all I can think of for the concrete spec section off the top of my head right now. Jerome J. Lazar, RA, CCS, CSI, SCIP Senior Member Username: lazarcitec Post Number: 1394 Registered: 05-2003 Posted on Thursday, June 11, 2015 - 09:49 am:    This client never advised us that there would be any polished concrete, all floors were called out on the drawings to be stone over concrete, tile or slabs was never defined. The Structural Engineer agrees. Of course now the architect says different, Colin Gilboy Senior Member Username: colin Post Number: 403 Registered: 09-2005 Posted on Thursday, June 11, 2015 - 10:38 am:    I set up a separate section for concrete toppings that would be stained or polished in Division 9: http://www.4specs.com/s/09/09-6230.html Colin Gilboy Publisher, 4specs.com 435.200.5775 - Utah 800.369.8008 Michael Chusid, RA FCSI CCS Senior Member Username: michael_chusid Post Number: 48 Registered: 10-2003 Posted on Thursday, June 11, 2015 - 11:13 am:    I know several project where a topping slab was poured over the structural slab, then polished. The reasons were: 1. Structural slab was a work platform and subject to lots of abuse. 2. The structural slab did not need careful leveling or floating. And, 3) The topping slab was integrally colored with select aggregate. Polishing requires a densifier for the concrete. You can download an article I wrote for Construction Specifier at http://tinyurl.com/qjrpdmq. I have written guide specs for densifiers, yet still remain baffled about the best way to specify - describing the process or the visual results. Michael Chusid, RA FCSI CCS www.chusid.com www.buildingproduct.guru ken hercenberg Senior Member Username: khercenberg Post Number: 914 Registered: 12-2006 Posted on Thursday, June 11, 2015 - 12:04 pm:    I like this website as a cheat sheet: http://www.concretepolishingassociation.com/specifications.php Look around on the website. They have examples of language I've found very useful when specifying polished concrete. The structural engineers I've worked with couldn't care less about the requirements as it does not affect the structural aspects of the concrete but each person is different. Some engineers don't want architects messing with their specs and I'm fine with that. Still, you'll either need to modify their spec or add a concrete finishing spec for the concrete installer to follow before the work gets handed off to the polishing folks. Preferably, the polisher will get to handle the finishing and curing as soon as the concrete is placed to get the best job possible. I've also found that, sadly, many firms who specialize in concrete sealers, toppings, and finishes really cause more problems than solutions when dealing with polished concrete. If you can track down a gent named Jim Cuviello (see my LinkedIn page to find him), I believe you will have an ally for life, even if he doesn't do your polishing. He lives and breathes this stuff and is an incredible resource. I'll sing his praises all day long. Sheldon Wolfe Senior Member Username: sheldon_wolfe Post Number: 860 Registered: 01-2003 Posted on Thursday, June 11, 2015 - 12:32 pm:    As Dave said, it's not a topping, though, as he and Michael suggest, a topping can be polished, and there are good reasons to do that. I have discussed polishing with a number of polishing subs, including Jim Cuviello, on LinkedIn, by e-mail, and in person, and have concluded that polishing concrete is more art than science. Other than the general process (apply chemicals and grind) there is little agreement. We have done several projects, and learned from each. Our polishing section continues to evolve, as no matter what we specify, the next installer wants to do something different. Mockups are essential, and allow us to get at least close to the desired finish. As Liz noted, coordination between spec sections and between the concrete and polishing subs is critical. The biggest challenge is managing expectations. Although it sometimes is called "poor man's terrazzo" it is not terrazzo and does not perform the same. Some owners apparently have seen the promotional pictures of polished concrete, heard that it's much less expensive, and decided that's what they want. Here's a LinkedIn discussion in the Concrete Polishing Contractors group: https://www.linkedin.com/grp/post/811967-5851754814861500420 J. Peter Jordan Senior Member Username: jpjordan Post Number: 844 Registered: 05-2004 Posted on Thursday, June 11, 2015 - 01:22 pm:    One of the very few instances that I have gone rogue on MasterFormat is polished concrete. I maintain that this is a case where the MasterFormat task team looked at the word "concrete" and did not consider the "work result". Concrete polishing, in my view, is a finish operation and a "concreting." The concrete guys don't have anything to do with polishing except to provide an acceptable substrate. Because the structural concrete surface may not be acceptable (expecially where colors are to be used), toppings are sometimes use to provide a more uniform polishing substract. Mark Gilligan SE, Senior Member Username: mark_gilligan Post Number: 743 Registered: 10-2007 Posted on Thursday, June 11, 2015 - 02:09 pm:    While there is a need to coordinate the cast-in-place concrete specification with the polishing the actual specification of the polishing should be in a different specification section.