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Acclimatizing New hardwood Flooring

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Acclimatizing New hardwood Flooring

#1

Acclimatizing New hardwood Flooring

John W Foster

We took delivery of our new hardwood flooring the middle of last week. Every flooring manufacturer seems to recommend an acclimatization period before installation. I did a bit of online research and found a lot of so called experts suggest that we should progress not according to a specific time, but according to moisture content.

The flooring is solid walnut 4 1/2" wide, pre-finished with one of these supposed multi layer abuse resistant varnishes. The supplier does every step of the process from cutting the tree to delivery to the consumer. Apparently when we ordered ours there was a batch of walnut fresh out of the kiln and it was finished about a week and a half later.

I have read online that for flooring that is the width of ours we should wait until there is no more than a 2% difference in moisture between the flooring and the sub floor. According to my Timber Check meter the sub floor is 9% and the flooring is 6% or less ( the lowest the Timber Check reads ).

Should I wait for the 2% difference? how long will it take? We will soon be starting to run the forced air furnace which I assume will dry down the sub floor more quickly than waiting or the flooring to take on moisture.

We are patient people and don't really care about waiting if it is needed.

Any Advice?

Thanks

Re: Acclimatizing New hardwood Flooring

#2

Re: Acclimatizing New hardwood Flooring

Dick Coers

Based on your moisture readings, the floor will be expanding if it gets installed now. Does it have finish on both sides? If the subfloor is wetter, possibly only the bottom of the floor boards will expand and the wood will cup slightly. I have no experience with floor installation, so can't comment on wait time.

Re: Acclimatizing New hardwood Flooring

#3

Re: Acclimatizing New hardwood Flooring 

Walter Ahlgrim

Me floor is a 2,3and 4 mix on widths and worried about cupping. The only place it has been a problem is where the door leaked water under the floor and a squeaky spots in February.

Spread the boxes out as much as possible if you must stack them be sure put sticker between them.

Opening the ends of the boxes may speed things up.

Personally I do not believe moisture meters are accurate across species.

The best test is to pull a few boards from the center of a boxes and weigh them using a kitchen scale that will display tenths of a gram. Writing the weight in the board every 3 days at some point the weight will stop changing or change very little then you are good.

Walta


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Re: Acclimatizing New hardwood Flooring

#4

Re: Acclimatizing New hardwood Flooring

Barry Irby

As a Builder and then Home Inspector, I have lots of experience with this. I could type out pages of horror stories, but I won't unless you ask.

Acclimating the flooring is a good idea. Go to the National Wood Flooring Association and print out their PDF on flooring, or at carefully read the first two chapters about the building and Guide Lines for acclimation.

Notice they are touchy about crawl spaces and ventilation.

Basically open the boxes if any and let the floor acclimate for a few weeks and get within 2% of the surrounding wood.

Also pay attention to the nailing. In short, Nail the hell out of it.

On my personal floor I spent time getting the subfloor very secure and flat. No squeaks, no humps or dips, screwed it down. Paid off.

Re: Acclimatizing New hardwood Flooring

#5

The problem

Bill Tindall, E.Tn.

Equilibrating floor with finish on it is going to be SLOW! Presuming the bottom is unfinished it is going to respond to the floor moisture, which presumably is equilibrated to the room humidity, and the top is going to lag considerably with risk of cup. And 4 1/2" is wider than I would have risked even with every precaution. Screw up and it will buckle and stay that way forever.

Lumber is typically dried to 7%. I am surprised at the 6% reading if indeed it is accurate. It is difficult to measure lumber less then 10% with a meter with much accuracy. I would confirm by oven drying and measure that way.

9% for wood inside an air conditioned environment in the summer sounds reasonable . The relative humidity of this room is a better measure of what the value is.

Given the price of walnut this must be an expensive floor. There is a lot to know about laying a floor. Hiring someone that is experienced, and bonded, could be a fraction of the floor cost with the guarantee it will be right

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