| Author |
Message |
Anne Whitacre, FCSI CCS
Senior Member
Username: awhitacre
Post Number: 1431
Registered: 07-2002
| | Posted on Wednesday, November 08, 2017 - 06:13 pm: |    |
I did a search of 4Specs and found that the last discussion regarding concrete slab moisture remediation occurred back in 2010. I wanted to get an update for what people are using (if anything) and thinking about using.
From my perspective, there are two types of systems out there: integral concrete additives, usually priced for a 6" deep slab; and topical coatings, with a Per square foot applied cost.
I don't really think these are that necessary, but the product sales people are now going directly to owners and we are being directed to use some product or another on some projects. (and I don't object to using them in DNA labs, or other labs with extreme infection control measures).
So, I want to take a survey of this group -- using moisture mitigation? not using? using additives or topicals? Anyone actually have a problem that required them? Are you doing this as an alternate for pricing, or just including them in your specs? |
Jeffrey Wilson CSI CCS SCIP
Senior Member
Username: wilsonconsulting
Post Number: 239
Registered: 03-2006
| | Posted on Wednesday, November 08, 2017 - 06:39 pm: | |
I include a Moisture Vapor Emission Control section for topical treatment in every project that has new slabs and moisture-sensitive floor coverings. The spec states that treatment is not req'd, but the spec'd systems may be used if necessary to make slabs ready for flooring application.
The contractor is welcome to sequence the work or use other drying methods to get slabs ready for flooring, so the spec does not pose an obligation or involve a cost if mitigation is not used.
Jeffrey Wilson CCS CSI SCIP
Wilson Consulting Inc
Ardmore PA |
Steven Bruneel, AIA, CSI-CDT, LEED-AP, EDAC
Senior Member
Username: redseca2
Post Number: 619
Registered: 12-2006
| | Posted on Wednesday, November 08, 2017 - 07:48 pm: | |
I include testing requirements in each flooring specification in Part 3 Examination/Preparation. These all refer to a Slab Moisture Control specification Section I provide for locations where the test results are unacceptable to the flooring manufacturer. I reference all of the test procedures and specify they should use the test procedure that the flooring manufacturer references to define their requirements.
The remedial procedures are topical and assume a fully cured slab. Our projects are usually large healthcare projects Where there are many months between pouring concrete, building close-in, and flooring installation.
Various projects include an allowance or a unit price for the remedial work.
I am neutral on the integral admixtures, as long as my testing requirements and remediation spec remain. I leave those to the structural engineer to include in their mix design.
I stopped specifying the "same day as pour" topical types years ago, after they conflicted with the structural engineer's curing requirements on a couple mega-projects.
Whenever this subject comes up, I always like to add that my first personal experience with a flooring failure occurred in a restoration project. The slab where the flooring failed had been poured in 1908, shortly after the great earthquake in San Francisco of 1906. This was in 1991, so I assume it was fully cured after 80+ years, but it did get rained on a bit during construction when the roof was off. |
Phil Kabza
Senior Member
Username: phil_kabza
Post Number: 599
Registered: 12-2002
| | Posted on Wednesday, November 08, 2017 - 10:13 pm: | |
Pretty much what Jeffrey does. The MVEC section is there if the contractor needs it. We reference the manufacturer of the flooring and adhesive for moisture test requirements. If the moisture tests are too high, the contractor may use the MVEC section at their cost, not the owner's. We spec moisture curing for all slabs to receive moisture sensitive floor finishes, as it (paradoxically) results in slabs with lower moisture content by the time flooring is to be installed. Careful mix design can also help with lower slab moisture content, as does avoiding specifying excessive cement content and excessive compressive strengths. |
ken hercenberg
Senior Member
Username: khercenberg
Post Number: 1126
Registered: 12-2006
| | Posted on Thursday, November 09, 2017 - 08:57 am: | |
Great points Phil. Lower cement content means less water. Lower water-cement ratios also help as does wet curing. Proper protection during construction is critical because every time the concrete gets wet, the drying countdown restarts. Don't confuse curing with drying. Curing happens pretty fast; drying, not so much. Heating the top surface can drive moisture down only for it to return when the heaters are removed and your flooring still fails. Dryers are a much better option.
I won't use admixtures for this. I have yet to see the chemical that will achieve the desired end result especially once the concrete starts to crack. Spray-and-pray topicals are also suspect in my book. Like some other folks here I prefer to include an old-school epoxy system in a stand-alone Section, cross-reference it from the finished flooring specs, and leave it to the Contractor to comply with flooring manufacturer requirements.
Just curious, has anyone here tried Laticrete's Supercap system? I'm intrigued by it but I'm not a fan of sole-sourcing a system. Including it as an alternate doesn't seem like a practical option for most projects. |
J. Peter Jordan
Senior Member
Username: jpjordan
Post Number: 1005
Registered: 05-2004
| | Posted on Thursday, November 09, 2017 - 10:09 am: | |
After hearing other specifiers around the country report difficulties of installing roofing systems over concrete (especially light-weight structural concrete) related to roofers and manufacturers refusing to accept concrete as an acceptable substrate, I am wondering if any of these moisture mitigation membranes might be acceptable to the manufacturers.
J. Peter Jordan, FCSI, AIA, CCS, LEED AP, SCIP
|
Chris Sanders
Senior Member
Username: chris_sanders
Post Number: 12
Registered: 05-2016
| | Posted on Thursday, November 09, 2017 - 03:23 pm: | |
On a somewhat related topic, how do you coordinate slab moisture/alkalinity requirements for various floor finishes, with the claims from concrete admix manufacturers that these requirements are not important? Here's a recent example of one manufacturer's standard Part 3 text:
"For concrete dosed with [product] admixture to receive adhered flooring systems, existing slab moisture and pH levels are not germane to the substrate readiness for installation. Flooring substrate testing shall be revised to conform to ASTM F710-11 X.2.3 (Short Term Bond Test)." |
Anne Whitacre, FCSI CCS
Senior Member
Username: awhitacre
Post Number: 1432
Registered: 07-2002
| | Posted on Friday, November 10, 2017 - 07:16 pm: | |
Ken:
the recommendation I've made to the office is that if we're going to use one of these things, then I want it to comply with ASTM F3010 (which at least provides an objective standard of comparison). Laticrete doesn't comply but Ardex MC Rapid does. (as does a product from Kosters, Floorseal Technology and Aquafin). |
Anne Whitacre, FCSI CCS
Senior Member
Username: awhitacre
Post Number: 1433
Registered: 07-2002
| | Posted on Friday, November 10, 2017 - 07:19 pm: | |
Peter:
I've also been involved in repeated conversations with the roofing guys because we use a lot of light weight structural concrete decks out here -- and have the roofing moisture problems. One of our local guys says to always use a vapor barrier on the concrete deck and the deck is ready for installation if they can do a pull test -- and the deck passes. Its possible that a moisture mitigation coating may interfere with adhesion of the roofing components. If we end up with that, I'll be able to combine the two problems that are making me crazy -- moisture mitigation reps and roofing installers. I can't say I look forward to that day at all. |
Guest (Unregistered Guest)
Unregistered guest
| | Posted on Friday, November 10, 2017 - 07:35 pm: | |
Anne, unless you know something we don't, Laticrete's Supercap moisture vapor control product does comply with ASTM F 3010 (as noted in their data sheet): https://cdn.laticretesupercap.com/~/media/datasheets/lscds0610.ashx?vs=1&d=20160209T163601Z
It seems like every week I'm finding another one of these products that meets ASTM F 3010 (the Laticrete product above was this week's). A few years ago when the standard was released it was somewhat rare to find products that complied, but now it seems to be all over the place. |
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