Has anyone had any experience with Barrier One High Performance Concrete Admixture (see http://www.barrierone.com/). This company claims to have developed a product that will eliminate concerns about moisture in concrete slabs interferring with flooring installations. They offer a pretty good warranty, but I really don’t understand how it would work.
Please note that I am only speaking my personal opinion and that this does not reflect in any way an opinion from my company.
Having said that, I would strongly suggest staying away from this sort of product. I’ll take a spray-and-pray over this any day, and I’m not a big spray-and-pray fan. Most other chemical companies who make silicate products won’t touch this method of application. They understand the chemistry and physics involved much better than I do (my major in college was Physical Sciences) and they are adamant that it does not work. I believe them.
First - I have to state, as does Ken, that this is my personal opinion and not necessarily that of my employer. I too do not like the “spray-and-pray” products and tend to stay away from them in favor of more “bullet-proof” systems.
Our office also believes that this product looks “to good to be true” so we assume it is not. The best method for moisture issues in new slabs will always be time.
In addition we have been revising our specs to include more wet-curing where possible as well as working to avoid the hard steel trowel finish that so many installations have. The steel trowel looks nice but tends to slow the drying process. We also have been eliminating “cure and seal” because the seal part does just that and then the slab is less likely to dry out in time for flooring installation.
Time is money and as such waiting is not always an option but it should be considered if at all possible. There is also a rapidly expanding library of superior adhesives that will allow a much higher RH and still warranty the system. I do miss the “good old days” when you could apply cut-back adhesive to the back of Rhinoceros and the tiles would have stuck.
Peter and All,
I just sat through a presentation with Barrier One at the CSI Vermont meeting last Thursday, 3/21. As a flooring distributor and installer, concrete MVER is a huge issue that we face on almost a daily basis. I wrote a blog post about it late last year here: http://ericdlussier.wordpress.com/2012/12/04/know-your-floor-and-know-your-mver/
I will say that the presentation was impressive. We have a former employee who works for a concrete testing company and they have been hired during concrete placement by Barrier One.
While concrete moisture is always there and is always an issue, our biggest headache is the timeframe that flooring has to be installed vs. the time that a space is truly deemed ready. I’ve seen wood flooring installed while front doors and windows less than 100 feet away are still not installed. We all could use acclimated spaces earlier in the project.
It does sound too good to be true, but that in itself does not mean it doesn’t work. And I certainly can’t speak to the chemistry. It’s possible the manufacturer is a bold face liar, and/or just dead wrong. But the manufacturer has significant amount of the product installed, and is completely open with its project references. The question in my mind is this: Are there any reports of it failing? Considering the potential upside of this product, collecting such real-world experience [good and bad] seems worthwhile, and is what I think Mr. Jordan hoped to accomplish when starting this topic. I would sure like to hear it.
There are bold architects and there are old architects; there are very, very few old bold architects. Spec writers tend to get less bold younger.
There are a few concrete additive systems out there now that promise more consistent finishing and better consolidation. On one of my previous projects, we used iCrete, and the contractor was able to reduce the slab thickness by 2 inches and consistently finish 2 floors every three weeks. For an 80 story building it was substantial savings in time and space. Their system involved continuous measurement of the moisture level of the concrete as it was pumped, and then an additive was put in either accelerating the mixture or retarding it, depending on the characteristics of the mix that day (relative humidity, absorption of the cement, etc). I think the industry is going toward optimized mixes, but it does take some skill to interpret the result and adjust the mix.
Reducing slab thickness affects the fire-resistance rating (ASTM E119) of the slab. For many of our projects, that was the determining factor in deciding slab thickness. Check this before you use this approach.
What was it about the admixture that allowed the slab thickness to be reduced??
“what was it … that allowed slab mixture to be reduced”. My understanding is that it was easier consolidation, and higher strengths. We’re not talking 6 inch slabs to 4 inch slabs – it was more like 13" slabs reduced to 11" slabs. it was a Type 1 building, and a concrete frame, not a steel frame. The project was built in New York City, and the contractor had experience with the optimized mixes and the measuring equipment.
Firsts realize that NYC is in its own universe when it comes to construction practices.
When I checked out iCrete it appears to be a software package that helps the concrete supplier optimize the design of the concrete mix. iCrete is not an admixture although the mixes produced probably use admixtures.
They could have produced the higher concrete strengths without the software.
There are admixtures that help reduce problems with congestion that are used all the time.
Reducing the slab thickness will increase congestion.
Reduction in slab thickness was likely the result of the Contractor and engineer doing cost studies considering the tradeoffs between added cement and reinforcement versus the cost of the concrete reduced.
Gee, I thought California was the only one in its own universe!
As an Architect and not a Structural Engineer, I’m still leery about additives/admixtures to concrete, especially when it comes to MVE.
As I mentioned, I like the applied products that can be applied over both new and existing slabs (which by the way can still have moisture in them).
Any one remember the old “ChemComp” product that was supposed to eliminate shrinkage cracking in concrete slabs? To my recollection, it never worked.
Admixtures can reduce the amount of water in the mix and reduce the permiability of the concrete.
Some admixtures appear to be able to trap the moisture in the concrete and prevent it from migrating to the surface. Some admixtures can also help small cracks to heal.
Will this solve your moisture problem? I do not know in part because it is not clear what the problem really is.
Tests have shown that the permiability of concrete does not account for enough moisture to cause the moisture tests to fail. This suggests that the moisture is comming from another source.
It has been suggested that the surface ph of the concrete plays a role.
In my experience there are a lot of individuals who claim “the solution”. Most of these experts must be wrong. What I do not see is a lot of science.
In this context as a structural engineer I attempt to keep the water content low and then try to accomodate the architects strategy.
Mark, I concur with you. The less water in the concrete, and the better job the Contractor does at keeping the concrete dry once reasonable curing has been completed, the better.
I learned a lot about this from Bob and Craig Higgins at Sinak in San Diego. They were among the first developers of ‘spray and pray’ systems and quickly learned that what worked logically didn’t necessarily solve the problem. They warn against the snake oil people who use silicates as admixtures.
A couple essential problems with the spray-and-pray systems are that if either the water (whatever form) or high pH layers are too close to the surface, the silicates react too soon and can’t penetrate into the concrete where they do the most good. Different silicates provide different levels of defense, so sodium silicates (like Ashford Formula) help densify the concrete which, when it is crack-free, is inherently waterproof but is still vapor permeable. Other salts, like potassium silicates, have a smaller molecular structure and should help block water vapor in theory. Unfortunately, if high water vapor migration is present, the silicate reacts too quickly to offer any benefit. If there is no problem, it works fine (sorry, being cynical again).
One of the biggest problems I’ve heard about using Silicates as admixtures is that they can create unworkable concrete. Concrete applicators have told me horror stories about their inability to float the concrete after adding these products.
The discussions that were posted a year of so ago about how to deal with water vapor mitigation offered a lot of very good, real-world suggestions. I’ll put my faith in those practices before trusting something that everyone I trust tells me to stay away from. I love trying new products, but change for the sake of change is a sign of ignorance in my book.
Hope that helps a little. This is obviously a very simplified explanation and I’ve probably screwed up parts of it.
Ken
I do not disagree that admixtures can influence the ability to finish concrete but my impression is that the horror stories are often the result of the finishers not realizing the need to change their practices. There may be limitations on the use of the product but in many cases they can be mitigated. This is a classic problem when we specify.
We cannot address all of the ways that something can be screwed up thus we are dependent on the contractor’s active participation. What we have specified may be perfectly doable but if a contractor is not invested in making it work it is easy to blame the problem on the product of the specifier.
My guess is that if we did nothing, in most cases there would be no moisture problem. Adding admixtures to reduce permeability and trap the water in the concrete would solve many of the additional problems. Paying attention to heating the space and providing humidity control would solve most of the other problems.
Thus to the extent that these surface treatments work they are in many cases probably getting credit for solving the problem when there is no problem. But it is not in the manufacturer’s interests to identify when we really need to do something.
My guess is that the flooring manufacturers have used this focus on moisture flow from the slab to focus the problem away from themselves.
Mark
I would add one thing to the discussion about moisture flow in relation to the flooring manufacturers. The problem IMO has become an issue for flooring manufacturers and installers not due to increased moisuter flow but due to changes in adhesives. The elimination of high VOC and solvent based adhesives has left flooring isntallations more susceptible to moisture issues than they were in the past and this has created an entire “cottage industry” designed to counter this issue.
The easiest solution would be to go back to cut-back adhesives but for a number of reasons (most of them very good reasons) this is not an option. Making the adhesives better for the planet (and all of us on it) has had an adverse affect on the flooring industry. The new “better” glues just don’t stick like the old stuff. I don’t think the flooring manufacturers are trying to “focus the problem away from themselves” but rather trying to work with the hand they have been dealt.
I also believe that henry adhesives and others are well on their way to developing better adhesives that will withstand higher RH levels and in another decade this whole debate may be a distant memory. In the end I believe the “magic pill” will come from the adhesive manufacturers and not admixtures or moisture mitigation applications. Still we live in the present so we have to deal with it now and everyone is looking for quicker, easier and cheaper alternative to protect against flooring failures.
spiper: there are three things that have changed that influence the flooring issues.
- we don’t typically use as lean a mix as when I started working – we use higher water content and somewhat less cement content in the concrete mix.
- as you noted, the adhesives are water soluble, rather than solvent based.
- and most flooring is less permeable than it used to be. VAT (A for Asbestos) allowed small amounts of water to escape through the asbestos fibers. Carpet with jute back and hair pads allowed water to escape through those fibers. Even ceramic tile with 1/4" joints every 8 inches allowed far more water evaportation than the 36" x 36" tiles with 1/4 joints we use today. Flooring moisture problems are a confluence of all three problems. These days, we can add less water to the mix, and we could go back to solvent based adhesives. VAT isn’t coming back, and only the “greenest” clients I’ve got would be willing to consider a jute backed carpet. (and I have not installed a hair pad in eons.)
The problem isn’t the moisture in the concrete, the problem is what happens when it condenses in conjunction with a latex based adhesive in a condition where no moisture can escape.
Anne: I agree that all three items influence the situation but I would still contend that item #2 is far and away the primary reason this is an issue.
1)old slabs on grade(presumably leaner & with higer cement content) are failing in reapplications. It is not just new slabs where this has become on issue. (Old slabs probably fail due to poor vapor barriers and high moisture content in the soil and not the original mix)
2)Cut-back adhesive was tested to be successful for levels up to 25 lbs. This allowed a great deal of flexibility in terms of perm rate, vapor barrier, mix design, size or type of material.
3)I am not sure VAT was more permeable than VCT but either way the topcoat of wax creates a form of a vapor barrier anyway. I have been told that old waxes were actually less permeable than new ones so this would actually make old floors more susceptible and not less. (I may be wrong about this one but that is what I have been told.) IF this is true why don’t old floors fail at a higher rate? IMO because of the solvent based, dead dinosaur goo, cut-back adhesive.
In the end I don’t disagree with you but still IMO the adhesives are the real problem and they will become the solution at some point as well.