I've got a 2 story house over a vented crawlspace with engineered hardwood floors throughout that was completed construction in Sept 2016 in upstate NY. I had some initial high/low spots that were outside the 1/8" in 6' specification that were possibly subfloor or installation related. This summer I've developed some more visible spots where the floor exceeds the 1/8' spec. It looks like the floor is buckling and it is occurring on both floors. It has a rosin paper underlayment.

The contractor is saying " it is from humidity. That wood flooring will expand and contract."

I understand that wood floor expands and contracts but I don't believe it should be buckling like it is. What should I be looking for or asking the contractor to do? It's very noticeable and I don't want to live with what I have.

Thanks,

 

How was it installed? If it is floating, it is probably too tight. If it was glued down, the moisture is probably too high. Did the installer run a moisture test in advance? If not, he should have.

 

Interesting enough, I installed some hardwood flooring last Oct here in MI and this summer had some issues with buckling that caused me to have to pull up and reinstall 3 rooms of flooring.

Not as bad as it sounds but in retrospect last fall was very mild and despite letting the wood acclimate for 4 weeks I now realize that that mild weather was my problem.

Reinstalled this summer, hot and humid, floor was fully acclimated and not an issue to date.

Engineering wood is less prone but will still move with moisture.

 

Sorry, I should have included that in the original post. The flooring is nailed down. I can't speak for the moisture at time of installation. It was checked early March 2017 and the wood measured between 7.3 to 8.8% moisture. They tell me the wood was acclimated but I wasn't there to verify.

 

Sounds like a moisture problem.

 

Ok, I get that it's likely a moisture problem. But it's not from anything like moist concrete. It's both floors of a 2 story house and there is a vented crawls space under the first floor. So it's just the air humidity which I would not have expected to effect a properly installed floor the way it has. We did not have an overly hot and humid Summer. Does this sound like a properly installed floor? What can be done to fix it and prevent this from happening every Summer.

 

What type of expansion gaps were allowed for around the perimeter of the install? Check the flooring manufacturer installation instructions to see allowable runs without needing expansion gaps.

 

I can only see the edge gap in one section where the molding has been removed. It varies from 1/4 to 3/4" on the ends of the boards along a 4' section.

How important is the gap on nailed wood?

 

All floors expand and contract as do the subflooring that they are attached to. If there is no filler within the gaps (caulking), then the issues would most likely be moisture. Do an extensive check for leaks or other water sources. Make sure the crawl apace is dry.

You can upload a picture or two, but not sure if that will help us any. Was the flooring installed perpendicular to the floor joists or parallel to them? What type of subflooring and thickness do you have? Was the flooring random length boards or single length boards?

 

The flooring is engineered prefinished Oak 1/2" x 3 1/4" and is random lengths. The flooring is installed both perpendicular and parallel to the floor joists on the first floor and parallel to the open web trusses on the second floor.

The subfloor is Advantech. It has ESR-1785 printed on it.

The crawl space is dry
I've added some pictures. One shows some of the gap at the edge where the molding was removed. Another couple show the gap under a 6' level. They show two 1/8" shims towards the ends of the level and two 1/8" shims stacked in the middle with enough room to put another shim in the stack. The otther photo shows a spot with a 1/8" shim with room to spare a little further down from the larger gap in the other pictures

 

Here are the pictures as described in the last reply

 

With flooring you have deflection that occurs between the joists and is why flooring should always be installed perpendicular to the floor joists. If you have sections parallel, the issues you see may very well be deflection between the joists and are a result of improper installation.

 

It doesn't look like deflection. I definitely think it wasn't installed properly. I already know there were high spots at the time of installation that was improper subfloor prep where we took up the flooring in one spot. Now there are a lot more spots that our out of the 1/8" in 6' spec. The contractor is saying it was caused by humidity and therefore not his problem. I don't buy that so I'm trying to understand better what was done wrong to cause this.

 

Unless our terminology is different I see some installation issues with the floor not being level (weather it's due to being installed with or perpendicular to joists) but I don't see anything that looks like it is buckling!

Moisture has nothing to due with the gaps in the pictures, can you show us the buckling?

 

From the national wood flooring association

Part III – Subfloor Flatness and Integrity
A. Wood subfloors must be flat, clean, dry, structurally sound, free of squeaks and free of
protruding fasteners.
1. For installations using mechanical fasteners of 11/2” and longer, the subfloor should be
flat to within ¼” in 10 feet or 3/16” in 6 feet.
2. For glue-down installations and installations using mechanical fasteners of less than
11/2”, the subfloor should be flat to within 3/16” in 10 feet or 1/8” in 6 feet.


How was it installed?

 

Maybe I used the wrong term when I say buckling. It doesn't show up well in the pictures but I can see where there are peaks in the floor. It's a more subtle rise then just 2 boards bulging up. It's up around 1/8 to 1/4" in most places. It's a little subtle but definitely noticeable if you're looking.

The first and second photo shows a little bit of a peak towards the right end of the level

The third photo shows that same peak at the end of the level and then another one about 4' further up

 

A buckled floor is when two boards have a peak and has pulled the nails out of the floor, does not appear you have this.

So, in the pictures which way do the joists run, across the hall or along?

 

The open web trusses run across the hall so parallel to the flooring.

 

So that could explain the gaps, if the subfloor was not sufficiently stiff and was sagging between the joists then the flooring is just following the floor sags.

This does not seem like a moisture/water issue but an installation issue. As noted the flooring should be perpendicular to the joist so the flooring would have more support.