costco floor

Log Out | Topics | Search Moderators | Register | Edit Profile

Author Message Robin E. Snyder Senior Member Username: robin Post Number: 400 Registered: 08-2004 Posted on Monday, May 14, 2012 - 02:04 pm:    Anyone do work for Costco and know what is used for their flooring? I have a client who wants a floor "exactly like Costco". Thanks! Jim Donnybrook (Unregistered Guest) Unregistered guest Posted on Monday, May 14, 2012 - 02:13 pm:    if it's the shiny, bare concrete look, i have been told this is an Ashford Formula type penetrating siliconate product. Euclid and Dayton Superior offer equivalents, and I have specified all three of these on several projects. Liz O'Sullivan Senior Member Username: liz_osullivan Post Number: 48 Registered: 10-2011 Posted on Monday, May 14, 2012 - 03:02 pm:    I just asked the QuestMark rep that I know, and he said they do them. (Diamond-polished concrete) Raul Hernandez (Unregistered Guest) Unregistered guest Posted on Tuesday, July 30, 2013 - 04:10 pm:    Yes, Costco does the diamond-polished concrete. We had a client who asked for the same thing and did some digging to find this out. Anne Whitacre, FCSI CCS Senior Member Username: awhitacre Post Number: 1362 Registered: 07-2002 Posted on Tuesday, July 30, 2013 - 05:37 pm:    the thing that they aren't telling you -- is that if polished concrete is the finished flooring, the slab (if its new slab) has to be poured stiffer and flatter than it would need to be if a topping were put on it. We typically rely on a feathered topping slab to get a flat floor under finish flooring, and with a polished concrete floor, the structural slab is the finished floor. There are all sorts of concrete finishing companies coming out of the woodwork and not all can do the work. A good polished floor is more a matter of good workmanship, not especially a specific product. Ask for a mockup first, before they start the floor, and ask for project references. ken hercenberg Senior Member Username: khercenberg Post Number: 573 Registered: 12-2006 Posted on Tuesday, July 30, 2013 - 05:55 pm:    See http://www.concretepolishingassociation.com/ for the start of a set of industry standards that seem to work. As Anne points out, there's a lot more involved than just specifying some chemicals and grinding. I put polishing in a separate Section and require that the polishing/finishing company be included in meetings before the concrete is placed. Once the concrete is placed, it's too late to correct the installation. Richard Gonser AIA CSI CCCA SCIP Senior Member Username: rich_gonser Post Number: 47 Registered: 11-2008 Posted on Tuesday, July 30, 2013 - 06:31 pm:    Are you certain it is diamond polished? If so to what level was it done? I doubt that Costco would be spending $6-10/SF for floor finishing. Remember, those buildings reach 100,000 SF plus. At that size, they can get a better price. But it is still very labor intensive. I'm not saying you're wrong, this just surprises me. You can get a fairly good looking floor with just a simple heavy bodied sealer. John Regener, AIA, CCS, CCCA, CSI, SCIP Senior Member Username: john_regener Post Number: 654 Registered: 04-2002 Posted on Wednesday, July 31, 2013 - 02:38 am:    The intent of polished concrete, as I understand it, is to expose the top of concrete aggregates, for the appearance of (cheap) terrazzo. In the specs I wrote several years ago, concrete polishing is to done by abrasive blasting and grinding to scarify and abraid the surface to expose aggregates and create a surface with approximately the texture of 80 grit sand paper. Then, a polyurethane sealer/finish is applied to fill and level the surface. I assume this sealer/finish is more expensive than a hardener/sealer such as Ashford Formula but it has greater gloss. That's not the diamond polished finish that's the subject of this discussion. But, diamond polished concrete seems to follow the same concept as promoted a few years ago as a cost-effective way to achieve a decorative concrete floor finish that requires (allegedly) minimal maintenance, especially when compared to resilient flooring or broadloom carpet/carpet tile. I looked at the link, identified above, to the industry's diamond polished concrete master specification. I'm impressed that the industry produced a well-thought out specification with genuine guidelines. Just as with the polished concrete spec that I produced (based on info from the sealer/finish product manufacture), one of the requirements of diamond polished concrete that can be easily missed is the required flatness and levelness of the concrete floor: FF50/FL35. I checked Masterspec's evaluation document for concrete floor finishing. FF50 is the flatness required for a television studio floor. That is, flat enough so a wheeled television camera does not wobble when traversing the floor. Less than FF50, I believe means inconsistent depths of cut and variation in the size of exposed aggegate. If the depth of cut doesn't expose the aggregate, I wonder whether a less critical flatness/levelness criteria would suffice. Floor flatness and levelness are criteria that need to be carefully considered for appearance and cost. Grinding and polishing is supposed to be done with large machines for economy and to minimize surface variations. That's OK for a floor in a warehouse store but maybe not so for smaller, irregular floor areas. Five plus years ago, polished concrete finishing was touted for high-traffic corridors such as in a school. However, these corrdors are not very wide and have many corners and alcoves that require hand work with smaller grinders. I wonder if the cost of polished concrete, especially if colored concrete is used, is why I'm not seeing polished concrete for projects other than warehouse stores or projects which feature raw, exposed elements such as roof / floor structure and ductwork / piping / lighting fixtures. I found in the master diamond polishing spec that the slab should be placed on an aggregate base that is leveled using laser-controlled screeds. Depressions in the aggregate base and underslab vapor barrier are strongly discouraged. It has to do with water from the uncured concrete migrating down and pooling under the slab, where it later migrates up to the floor surface and causes inconsisten appearance. Also, variations in slab thickness are concerns, related to cracking of the concrete over time. Also, I found in the diamond polishing spec master that crack control joints should be approximately 10 feet o.c. and the divided areas should be approximately square. That means more sawcutting and greater quantity of sawcut joints to be filled with epoxy joint filler (to prevent spalling at the edges of the joints from heavy, wheeled traffic). Hopefully, the locations of columns will work with the relatively close spacing of control joints. The spec master also has some criteria for the concrete mix, including criteria for the appearance of the aggregate and limitations on admixtures, including fly ash. Curing compounds were discouraged yet the use of sheet curing and other means of keeping the concrete moist for the critical first 7 days of curing was not clear to me in the spec master. An acceptable finish probably can be achieved according to the industry's diamond polishing master specification, assuming skilled workers and proper techniques are used. I'm not convinced, however, that diamond polishing is suitable for other than large, unobstructed floor areas. And then, having checked out Costco floors many times, I wonder just how much diamond abrasive grinding is actually done and whether the premium cost of finishing is mitigated by considerations for cleaning and finishing costs to restore the floor slab after it is used for casting tilt-up concrete wall panels. What did that Mies guy say about the details? David J. Wyatt, CDT Senior Member Username: david_j_wyatt_cdt Post Number: 6 Registered: 03-2011 Posted on Wednesday, July 31, 2013 - 09:16 am:    Again, Anne is correct. Check the link John R. cited to be sure the slab is within the recommended flatness range. Otherwise, your client will have to pay a lot for additional shaving and grinding to achieve what is, in the end, a fairly utilitarian aesthetic. I did CA on a project last year in which the owner decided toward the end of the project that he wanted polished concrete. Heard it would save money and look like terrazzo. Wrong! The slab was not installed with that in mind. When it was all said and done, he got an acceptable polished concrete floor at the price of a high-end tile floor. Also, the prep and polishing made a mess of the building interior - Wood wainscot and trim beaten up, HVAC system loaded with dust, etc. The polished concrete industry has worked long and hard to elevate their reputation. If you follow their recommendations it can be a good, sustainable building element. But it cannot be a late-in-the-game decision. J. Peter Jordan Senior Member Username: jpjordan Post Number: 593 Registered: 05-2004 Posted on Wednesday, July 31, 2013 - 10:16 am:    There is a difference between what I call "high-polish" (very glossy) and "polish" (semi-gloss) concrete finish. Both of these far exceed the gringin requirements for terrazzo, typically 80 to 120 grit. Generally, there will be a grinding phase initially and then polishing with successively finer grits (to 3000 grit for the high polish finish). Floors must be flat (as opposed to level) or the risk is that bands of aggregate will be exposed. The caveat I always give is that polished concrete finishes are only as good as the concrete slab that they are done onm and they are not impervious. Most specs will include a sealer (which must be maintained). Without this step, the floor finish may be permanently stained by mineral or vegetable oils or it may be etched by acidic liquids (pickle juice, tomato, or orange juice) which will be noticeable on a high polish finish. Polished concrete, in my opinion, has been oversold. It can be a good solution in some areas, but is not appropriate every where. Recently I wrote a spec for a "burnished" finish for a troweled concrete floor and a ProSoCo product that is supposed to result in more "shine" than plain concrete, but not as much as polished concrete finish. John Bunzick, CCS, CCCA, LEED AP Senior Member Username: bunzick Post Number: 1520 Registered: 03-2002 Posted on Thursday, August 01, 2013 - 09:05 pm:    Anne is right that there is no opportunity to make a flatter floor than offered by the structural slab. However, that does not mean that the slab has to be especially flat. It depends on your project. For schools with VCT, we may get some minimal flash patch type of leveling, but no more. With polished concrete, that is still flat enough. Some polished floors have a sealer to reduce staining, such as from food, but most of the durability comes from the hardeners used in the process. Polished concrete is also a bit like wood in that it is probably not going to be totally uniform. That is, unless you have a really flat floor and you use a fairly aggressive grind to expose much aggregate. With a modest grind, and a less-than-glossy finish, it can be a competitive floor treatment. J. Peter Jordan Senior Member Username: jpjordan Post Number: 595 Registered: 05-2004 Posted on Friday, August 02, 2013 - 07:47 am:    The other factors affecting the appearance are variations in concrete mix and curing and patching. patching materials for trenching, filling, and surface corrections will always be different in appearance from the "base materials." Even the best mockup cannot address all conditions that will affect the final appearance. Managing expectations is important since this is a work result that cand cover up a surface that "is what it is." As someone noted above, sequencing may be an issue. Most concrete polishers will prefer to polish early (before partitions are erected), but protecting the surface from damage during the rest of construction. Polishing later (but before AC is activated and finishes are installed) will result in additional hand work at edges where partitions occur as noted by John above), as David noted, a very late decision to polish can be very messy or more expensive to mitigate the mess.