History: Bruce 3/8" solid maple product, glue down onto slab. Professionally installed.
Enviornment: El Paso, TX We have "swamp" coolers (evaporative cooling)
With these coolers we see a significant swings in our humdity levels in our house between seasons

Now: Solid maple is buckling.. more severe in some spots than others. Also installer has some concern glue may not have fully adhered.

Question: Our outstanding flooring company is fixing our issue (replacing entire floor) and I'm very happy with their service, despite the issue with the flooring. But my wife and I are considering putting down an engineered product as opposed to the solid maple. Speaking with the installer he indicated that engineered floors tend to be much more resistant to humidity than solid wood. I'm sorry I don't have specific RH data to provide. I can say our problem didn't become visibile until we had a period of heavy humidity & rain (no, there is no leak from exterior and the slab itself seems fine. Our installer was fairly certain the problem is coming from humidity in the air)
Also - With swamp coolers I really do not believe there is a way to control the humidity to any great extent other than to be careful and turn off the coolers once the humidty starts to rise outside.

Additional Question: As they are going to "tear out" my glued down floor, what questions should I ask them about their method? What can go wrong during the tear out? What condition does the floor need to be in prior to the new installation?

We love our solid maple product, but I am scared to death the same issue will happen next year during the rainy/humid season.

Thanks for the help...

Solid maple should have never been put down over concrete without an overkill moisture barrier system!!! But if your running swamp coolers, humidity must be very low, which can cause cupping. Only a hygrometer, and a moisture meter can varify what's happening.


Engineered will be much more stable, but only to an extent.
You may still need to raise the humidity levels, or you will see checking/cracking in the engineered.

Thanks for the reply. My installer has not spoken to us about a vapor/moisture barrier. Reading the many posts here the Bostich (?) MVP product (if I got the name correct) seems like a preferrred method. I believe the installer indicated they would use Bostich Best for the glue material (this time).

What should I tell them with regard to the vapor/moisture barrier?

Thanks in advance....

Guys,
What range should the hygrometer be reading, 40-60%, is that OK?
Donna

40-60 is about as low as most can get the interior around here, although I walked into a cupped and cracked floor, that the rH was 19% inside the home.

Your sounds like concrete moisture emissions that are very high, if the rH is 50% average, and you have cupping and buckling.

I would seriously expect them to check, test and document the concretes moisture emissions.

Not sure if you were replying to Donna or myself in regards to the concrete emissions. The installer did a quick moisture test on the slab where it buckled and said it was dry. His opinion (for my situation) was that there was too much humidity in the air. As I indicated before, I'm not entirely sure about the RH, but I've got evaporative coolers and we did go through a very humid period recently... if the air got to 80% - 90% RH in the house for several days, could that be enough to buckle a good installation? Or would there also need to have been some other issue?

-- Kent

40%jumped to 60%, is enough to buckle a maple wood floor.

( Yes... I've got lots of questions.. but I really do appreciate all of the help!)

Will an Engineered product hold up better to these humidty swings?

Are there any industry guidelines I can use to better understand what I am up against here (relative to RH swings in the house) ?

Once again... thanks so much for all the great advice!

Kent,
Sorry to butt in to your post, I think I confused the guys. I have a engineered Maple floor. The manufacter specs. say to keep the home at a relative humidity of 40-60% at all times. You can use a humidifier or a dehumidifier, or A/C to keep the relative humidity. I live in Chicago, which sounds very different from Texas weather. You need to purchase a Hygrometer to check humidity.
floorguy, help him out, I shouldn't have hijacked his post.
Donna

Perfectionist,

No problem. I just appreciate the advice!

Actually I purchased a Hygrometer and had it up and running yesterday. ("Taylor" brand, cheap, not sure how accurate it is.. hopefully no more than 5% inaccurate)

Here is a chart on our RH for El Paso (assuming it is correct). Top line is the morning average, bottom line is afternoon average:

Relative Humidity by Month (Percentage)
Jan. Feb. Mar. Apr. May. Jun. Jul. Aug. Sep. Oct. Nov. Dec.
65% 55% 47% 39% 41% 46% 61% 66% 66% 63% 61% 65%
34% 27% 21% 17% 17% 19% 29% 33% 33% 30% 33% 38%

To compliate matters we use evaporative cooling. As an example I set up my hygrometer last night it initially was reading 54%, after cranking down the coolers (causing them to run) by morning the reading was 69%.

As I've indicated there are many swamp coolers in El Paso and apparently they install plenty of hardwood on slab here... so I assume it's possible to have a good installation/experience, but I'm trying to better understand what I'm up against. We can probably protect against major humidty swings above 70% (say when it rains out, shut of the coolers and close the house up), but I think we have to assume that during the summer we'll be dealing with periods of 50% - 70%RH in the house.

Does this seem feasible? At what RH% should we get the house to for the wood to acclimate? Will an Engineered product give us a bit more piece of mind?

Thanks for the help....

An engineered floor will normally expand and contract much less than a solid floor will, especially maple, which is less dimensionally stable than the norm, ei: oak. So, IMO, yes, an engineered floor should withstand wider swings in relative humidity. This is not to say you might NEVER experience a problem, no one can guarentee that when the environment is out of the norm, which is generally considered to be 40 to 60% RH.

Do you have A/C that you kick on once the outside dew point gets above 55 degrees? That would cause huge swings in RH, since A/C removes moisture from the air and evap coolers add moisture.

I'm certainly no expert, but it strikes me that the most important thing for wood floors is not so much the value of the RH, but the consistency of the RH. I'm in Phoenix, but I don't have evap cooling, just A/C. So my house is bone dry year-round. My new floors have been acclimating for two weeks. I'm doing one room at a time, so most of it will have sat for a month or more before it gets installed.

If you're running evap, acclimation will be extra crucial. By definition, you are in a dry climate (or else evap cooling wouldn't work). That wood may have sat in a non-climate controlled warehouse for months getting nice and dry. The inside of your house is very humid.

What kind of heat are you running in the winter? If it's a drying heat (like electric forced air), you might want to add a humidifier to keep the inside RH more constant. That's probably more practical than a dehumidifier in the summer, since that would certainly be a losing battle with the evap cooler. Heck, a humidifier will reduce the swelling/shrinking cycles of your doors and even help prevent those chapped lips and dried out nasal passages in the winter.

The moral of the story: Give the wood plenty of time to acclimate to your humid inside environment, and do your best to keep the RH up in the winter with humidifiers. It's better for everything, not just your floors.

Good luck!

I think you make an excellent point. Maybe I have been worrying too much about RH swings, and should focus on how to keep it more consistent. I'd be curious about your experience during the winter in Phoenix. What RH levels have you been able to maintian? Do you have an installed dehumidifier or stand-alone units?

(BTW, my cooling is 100% evap, no A/C at all... Gas Heat... I'm sure my RH in the winter is very low)

Once again... thanks for the help.

-- Kent

Kent,
I bought a good quality dial Hygrometer from Technika on the internet. The first time I used it the humidity seemed really high. As per the directions, I put it in a wet towel for 1/2 hour and the humidity was over 100%. I used a screwdriver to reset it to 95% and it then went down to 40%. It doesn't sound like humidity is your problem, but you Hygometer may be way off, read the directions on how to reset it first.
Donna