Many are surprised to find OLD slabs are VERY WET! - Printable Version
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Many are surprised to find OLD slabs are VERY WET! - CC Solutions - 06-13-2010 09:52 AM
I've had a recent rash of contracts where installers are removing successful floors to install new modern flooring and these installers find the old slabs are quite wet.
They are lucky if they do their testing BEFORE they install the new flooring, but sometimes these installers are shocked to receive failure complaints only a few weeks after installation.
Old flooring sometimes breathes better than what we install today, and the adhesives of the past are no longer allowed for modern installations. A slab that held a floor previously may not be suitable for new products. And those old 6 mil vapor retarders break down over time, so I advise testing on any slab where the pedigree is not known, or the slab is over 10 years old. Even then, I always put in a couple RH probes for peace of mind.
Better to catch that moisture before the installation and deal with it up front!
RE: Many are surprised to find OLD slabs are VERY WET! - Ernesto - 06-25-2010 06:45 PM
And so goes the theory of relativity that well...that if the wood floorover there is Ok, we're safe to throw this one down
RE: Many are surprised to find OLD slabs are VERY WET! - Basementredo - 09-20-2010 09:47 PM
I am new to this forum! This is not a reply, however, we do have a 45 yr old home and are approximately 3/4 of the way through a 2,500 sq ft basement rennovation due to a water heater giving out last Oct. Let me add, we have had the misfortune of hiring an unreliable, untrustworthy contractor so we do not trust/depend on his word with any issues that are going on downstairs.
It is VERY LATE to ask these questions, but the floor has not been installed YET!
Tomorrow the flooring installer arrives to supposedly put down the MVP sealer before the bamboo flooring is laid in our family/enternment area. The other two areas in our lower level will have Johnsonite rubber flooring--Exercise area; and Armstrong VCT -- Laundry room. Not sure what is being used for a sealer, but I plan on finding out Tues a.m.
Today, the contractor spent the entire day with a few of his workers, filling in cracks in the basement cement, scraping the floor, sweeping, vacuuming AND DAMP mopping. I mean it doesn't take much to clearly see, there is no way the floor will be ready for the installer tomorrow 8 am to come in and begin putting on moisture sealer. no way.
My husband and I placed a square of plastic in one of the rooms to test for moisture as that is what our contractor told us would suffice. HA. I now am aware of the Wagner Rapid RH device and will insist that the flooring installer use it to measure rh before any moisture sealer is placed on our floors.
My concern is that the flooring for the exercise room--johnsonite rubber and the family/enternment area are POOR choices as rubber does not allow a cement (foundation) to breathe and the Bamboo (cement foundation) will most likely begin to cup within 6 to 8 mos.
If after the Wagner test the rh is less than 75%, would you be of the opinion to still proceed with installing the bamboo and johnsonite flooring given our cement foundation? If so, what moisture sealer for these two areas would you recommend?
If not, what other types of flooring would suite our basement? We have invested quite a bit of $$ in this project. This rennovation has a very modern look, thus the bamboo flooring. Previously had wood floors in my exerc room & thought rubber would be a better option. Any input on what sealer to use beneath the rubber flooring and VCT would be appreciated. I don't know if the flooring installer will be 'on top' of any of this, but I want to be. My husband is on a short business trip and I am taking care of business at home!
I'm not feeling so good all of a sudden [/font]
RE: Many are surprised to find OLD slabs are VERY WET! - CC Solutions - 09-25-2010 11:07 AM
Welcome to the forum, and I wish I would have logged back on earlier!
You are wise to question the processes used to renovate your basement. So many failures happen every day, even with good intentions up front.
My background: This is what I do. This is all I do. Moisture mitigation. Not residential actually, but for medical facilities. Many hospitals use rubber floors, they are a wonderful choice! Low maintenance, long life, quiet and soft underfoot. I know you'll love your rubber and bamboo floors.
I would ask many questions to get a better picture of your situation, but based on what you have said so far the plastic sheet test is NOT reliable. A slab that old, even if a vapor retarder was installed underneath (unlikely), it would probably be degraded to almost nothing after all this time.
That said, all manufacturers will require following ASTM F710 which specifies a 'permanently dry' concrete floor with a moisture retarder under it. You probably don't have either of these conditions. This leaves two courses of action; install breathable flooring or seal the floor with a quality moisture sealing system.
The first option is easy to understand, the second is where you are, and I can assure you this is a worldwide problem. I replace 'moisture mitigation' systems all the time. Sometimes it's due to improper specification, sometimes the manufacturer has over-promised the effectiveness of the product and sometimes the reason is pure deception.
I will not recommend a moisture mitigation system here, but I can ask you to start by reading the warranty. Does the warranty extend to 100% humidity? With no real vapor retarder you could get there. And the big one, does it extend to unlimited alkalinity? There are companies promising 95% RH warranties but only up to 10 PH. So your floor fails and they open it and conduct an alkalinity test and of course it's high. Moisture and alkalinity go hand in hand.
Much of the validation will be based on floor testing and preparation.... be sure every detail is followed. Next look at the warranty recourse. Many manufacturers will provide replacement product if you prove their product failed. Or as I like to equate; 'Sorry your $10,000 floor failed (or your $50,000-a-day Operating Room is out of service) and you need to go through the heartache and mess to repair it, but we'll stand by our warranty and provide you with a NEW BUCKET of the same garbage that just failed'. This is not acceptable.
Now if your contractor uses one of the systems that meet all my fussy criteria and it is installed properly, you will have a floor that is free of moisture problems for a very long time, probably a lifetime.
Please PM me the product used and I will give you some background information on it. I really wish you the best of luck!!
RE: Many are surprised to find OLD slabs are VERY WET! - Basementredo - 09-27-2010 02:13 PM
Ok, don't laugh, i feel ridiculous...I cannot seem to figure out how to pm you. Where do I go, what is it I do....?
RE: Many are surprised to find OLD slabs are VERY WET! - CC Solutions - 09-28-2010 10:10 PM
Pm received and replies have been sent.
RE: Many are surprised to find OLD slabs are VERY WET! - Ernesto - 12-22-2010 07:37 PM
On topic, just a story. I walked into a house to install a glued down vinyl floor (Sundial Solarian) about 25 years ago. The house was easily fifty years old and the carpet had been torn out, even the old ceramic in the kitchen.
When you walked into that house you could literally smell the dampness. Maybe it's because we are used to dryness out here in the desert. But the concrete was very dark, effloresence was all over the place. Back in those days all we had was the concrete meter your contacts touched nails driven onto the concrete. Well the boss was PO'd I called him in the first place, but after he came over with the meter and tested it he was a happy camper.we averted disaster.
That always stuck with me to this day. We had been getting lots of rain down here and a couple floors blew off down in Nogales up in the hills. But those were new houses. Lucky us, we have great testing devices these days.[/i]