I bought my building a year ago in a Northwest suburb of Chicago., it had sat for about 3 years unfinished. Anyway we finished the buildout by May of 2011, the last two weeks were spent installing 2200 sq/ft of Mercier Hickory (engineered hardwood).

It was very expensive so we had the flooring company run 3 moisture tests on the concrete in different locations and they came back with flying colors, the results were verified and documented by some certification company as well, for warranty purposes. They decided to glue down the product and used some special (very expensive) moisture barrier adhesive. The material was acclimated for 7 or 8 days. Once installed I noticed a few areas where the were a few microscopic hairline cracks at the end of boards and on the surface of a few, but didn't really think much of it at the time... I figured it was hickory and there would be some inclusions.

Well about a month ago (8 months after install) I decided to get on my hands an knees and wash it. I used a water bottle with luke warm water and a cap of vinegar, lightly misted and used microfiber towels to clean and dry. While doing this I noticed there were allot of cracks on the surface of the boards and where they butt up against each other, by my estimation 20 to 30% of the boards are doing it.

Now when you look down the hall you can actually see the cracks raised on the boards. I immediately called my flooring guy he came out about 2 weeks weeks after I called (it was over Christmas and New Years). He brought a guy with him and after looking at the floor announced that it was to dry in my office and it was my fault for not having a humidifier. I reminded him about the humidity tests and he said that was for the concrete only. Now I'm real angry because if I needed humidifiers I would have bought them. Anyway, he left humidity tester and it is reading 25% (although it doesn't really feel dry) he said that it needs to be 35%.

The thing I don't get though, is that if it was due to it being to dry wouldn't the boards shrink and create gaps where the boards meet up with each other, because the spacing/seems haven't changed at all. A Mercier rep is coming out tomorrow from Milwaukee and I would like to be as informed as possible before he arrives. Any thoughts are appreciated.

Thanks in advance Mike

sounds like the installer is right. Its an installers responsibility to make sure the conditions are right at the time of installation. Its up to the owner to maintain those conditions, what we would often call "normal living conditions". the floor is changing shape because the low r/h caused from running the dry heat is drying out the top of the board faster than the bottom of the piece. the imbalance causes movement, in your case the top is shrinking a bit. If you run the humidifier and return the air quality to that of time of install the floor should close up. Hickory is a pretty unstable specie no matter what you do. a slight change in r/h will cause slight movement. all sounds pretty normal from your description.

http://www.hardwoodflooringtalk.com/gallery/displayimage.php?album=lastupby&cat=0&pos=0&uid=10064

I uploaded images into my gallery to show what's happening.

Thanks Mike

pictures are a huge help. thats checking/splitting not just some seasonal shrinkage. Do you know if that floor has a sliced or peeled veneer top?

Looks like "checking" to me..and was probably there form day 1..the environment just made them more pronounced..
judging the fotos..its the grading if material..very 'rustic'...so...my opinion..it was in the milling..

the manufacturer will probably attribute it to that.......

install some humidifiers into the system and I'm sure things will improve.

good luck, Id say the Guy will tell you its too dry and sorry for you trouble but there isnt much they can do but offer some advice. the warranty info which im sure you have read goes over the situation at hand. http://www.mercier-wood-flooring.com/pd ... ential.pdf

Thanks for all the replies so far. I have my HVAC guy quoting two 12 qt spray humidifier systems. If the checking is in the boards from day one then I would assume its a mfg defect being exasperated by the dryness.

I have to postpone the Mercier guy for a few days due to a family emergency so hopefully he can shed light on what is and isn't covered. I'll report back when I learn more.

Thanks again Mike

those humidification system they put on a hvac only work when the fan/unit is running. A stand alone sysytem will be more efficient and easier to maintain and a fraction of the cost. I know they are pretty ugly for the most part but they do work.

We are thinking of putting the Mercier Hickory Classic hardwood engineered flooring in our kitchen. After reading the issue with cracking---- we are concerned--- should we be? We are interested in any expert opinions and advice.

It seems the issue with cracking discussed is with regard to the install over concrete with vapor barriers but with too dry conditions.---We will not install over concrete. However, my concern is that the cracking could be inherent in the Mercier hickory itself regardless of moisture?---- is there risk? Is the issue with cracking truly due to dryness in issue discussed? Are we safe to use in our kitchen? We were told this a top of the line woodfloor...

A secondary issue is that we have a Armstrong inlaid vinyl floor over an original 1970's vintage asbestos vinyl floor. Must we remove and put in a subfloor at greater expense? or can we float? glue? staple? nail? What is recommended?

Thank you,
Milwaukee, Wisconsin (weather)

hi everyone!
we've installed engineer floors in condos (100+)in a building,and the end result was only 1 condo ask (it was extra)for a hvac humidifier that came with the air and heating system and theirs floors were great! they were 5'' white oak engineer with oil finish. they kept it at 43% r/h because she had a respiratory problem.
the other condos had all,no exeptions a crowning effect but with a gap in between each plank. we mesure in the r/h and averaged 15 to 25% .the engineered wood has a tendancy to look as if it was to humid but in fact is to dry.

so my suggestion is go to at least 45% r/h because such a big area with my guess high ceilings? will definitly need more humidity,40 to 50% is perfect.

sometimes the varnish can chip or peel so much the wood is shrinking so be careful...

Newfinish,

Thank you for your advise----

Pleasure
Let me know if you need anything else

http://www.weather.com/outdoors/home-im ... USIL0225:1
This website depicts the current issue in the chicago area. Now Outside 29 degrees 78% humidity inside thermostat 74 degrees produces 15% humidity. In El Paso this is pretty much a constant environment here.
Looking at the chart tying RH to MC it would produce a MC of 3.5% way less than the 6% normally allowed in most areas of the country, It takes quite awhile to produce 3.5% mc but wood science being what it is it will get there soon enough.
Acclimation is like putting a piece of iron in an oven at 400 degrees it will have a temperature at any given time but only after sitting in there for a certain amount of time will it reach a temperature of 400 degrees.
Moisture meters are the only definitive way to assess this.
Gaps with glue down hardwood after a period of time are almost always relate to reduced moisture content in the wood.

I have the http://www.amazon.com/Essick-4D7-800-Wh ... 000D8EJP/2

Ok sure it's ugly but I hide in behind a wall near a large air return vent that circulates it around the house. This is what I recommend to all my clients unless they have a small area or wood or house. That thing pumps out some water vapor. And it is digitally controlled.

Been thinking about covering it with some niceer veneer.