Thank you for your help and confirming what I thought about the 3/16" over 10ft span. Yes, this is a new build -- AND we mentioned our concerns 2 months prior to our closing date which is when they started installing the laminate. They lied and said it would be handled and addressed "well before our final walkthrough", then the day of our final walkthrough they informed us we had to pursue it with the flooring retailer (of which we did not have a choice in choosing the flooring retailer or installer) so we did -- and various people from both the retailer and the builder's side have come to look at our flooring multiple times...thankfully everyone is in agreement that something is not right. We've been working on this for the almost 4 months we've been in our home now. So, the pier blocks are step 1 of however many steps are needed to solve this. We're beyond upset about this because they will likely have to rip out the entire main floor for an issue that we mentioned months before moving in.

The particular laminate we have requires a moisture barrier less than 3mm on top of a wooden subfloor. We can't get around that, I've already asked. Obviously if they can't figure out how to fix the issue I will request a new flooring product.

Can self-leveling compound be applied to an OSB subfloor? I thought it could only be used on a slab foundation. That sounds like it would be ideal (assuming the joists can support the extra weight, I'm assuming that stuff is heavy) solution. I know for a fact that no subfloor prep was done beyond sweeping debris before putting down the moisture barrier. We were present during part of Day 1 install of the floor as well as mid-install on subsequent days. Not once did I see the installer with a level (I can't say for certain he didn't have one, but I don't have a single photo that shows a level anywhere). The retailer is Great Floors which is a terrible company...unfortunately we did not have a choice.

There are cementitious floating materials, trowelable and self leveling, that can be used on top of wood subfloor. It sounds like it wouldn't be very thick so weight isn't an issue. Also, slightly high spots could possibly be sanded down to get the floor within specifications.

Does your floor also have a foam underlayment? There are underlayments with integral vapor barrier under 3mm thick. Or a high quality foam like Floor Muffler or Silencer could be laid over your existing barrier.

I have seen plenty of complaints about creaking floating floors, usually related to unlevel subfloors or lack of expansion space.

BTW, putting a straightedge on the floor and pushing down on one end isn't generally a measure of level. You're only showing that there's a slope in one area and accentuating it with a straightedge. If you had a slope and a long enough straightedge, you could probably get it 2' high on the other end. That doesn't make it 2' out of level. The way to measure level is to use a long level set on a high spot, hold the other end up until the bubble is level and measure the gap from the floor to the level. Or you can do the same thing with a smaller level by setting it on top of a long straight board, shim it level and measure the gaps underneath.

The laminate planks have a foam pad pre-attached to them and the the plastic moisture barrier is loose-laid between the subfloor and laminate. It seems that maybe a moisture barrier with thin integrated pad could potentially help the crinkling sound (the cracking sound is something different).

I was using a 4ft level when measuring the floor and in several areas the edge of the bubble is outside of the guidelines slightly. When holding the level down at one end the bubble will show as level and at the other end there is a 3/8"+ gap underneath the level. And that is measuring on the extremely rigid laminate...I can only imagine the actual bare subfloor is worse.

Ugh, it just seems like a total nightmare to get this all fixed. Removing baseboards, tearing up the floor, etc...and since every room has issues and we have an open floorplan I'm not sure they can go room by room since they'd have to find the highest points and build up the rest.

That's pretty bad. I feel your pain but if you don't do it now it will probably never get done. Maybe the shoring from underneath will eliminate some of that.

Sounds like they didn't check the crown or use blocking between the floor joists. What material is the crawlspace floor? If it's dirt they need to pour a footer for each support, or it'll just sink over time.

UPDATE :

We just got word that our entire main floor flooring will be torn out and they will use Mapei self-leveling product on top of our OSB subfloor. Brand new laminate flooring will be installed.

Since our laminate has a pre-attached pad and *requires a moisture barrier under the flooring on top of the subfloor*, is there a different product we should request different than the regular plactic moisture barrier (ie: something quieter?)?

I would question the "requires moisture barrier". I would REALLY question that. The "requires moisture barrier" is normally reserved (only for) CONCRETE/CEMENT SLABS. As soon as a laminate is installed over WOOD (OSB, plywood, fibreboard = doesn't matter they are all wood based products), then the "requires vapour barrier" goes out the window.

The "requires vapour barrier" is for the CRAWLSPACE...the dirt/concrete in the crawlspace needs the vapour barrier - the OSB does not receive the vapour barrier. I would ask that you offer a link to your laminate brand so that I can read the installation instructions. I've read HUNDREDS of install instructions over the years and they are ALL VERY SPECIFIC. But the ONE PLACE they maintain consistency = wood subfloors vs. concrete subfloors.

"Best Practices" as set out by the National Wood Flooring Association state that wood based subfloors should NOT have vapour barriers installed over top. Concrete subfloors require vapour barriers when a floating floor is installed.

I'm sorry but something is wrong here. Very wrong. If you install a vapour barrier over wood, the moisture will gather underneath the plastic and then SOAK INTO the wood = full ROT inside of 10-15 years.

Please post the link. Let us look. If this is a product from "oversees" it is POSSIBLE the translation was written inappropriately (happens ALL THE TIME on Chinese import material). Post the link to your floor and we will check it out.

Cancork -- thanks for your help and knowledge. Here is the link for the flooring and if you look at the bottom of the page in very tiny letters there is a PDF link for the installation instructions : http://www.pacmat.com/product/calypso This is a Chinese flooring as far as I know. It's distributed by Pacmat but they told us it is "made" by Tarkett, though ours has the attached pad and is moisture-resistant with the special core. The floor itself is actually really nice.

Now that they will be using Mapei self-leveling product throughout the entire main floor, do we treat it as if it's a concrete subfloor (thus requiring the poly moisture barrier anyway)?

Ouch... that is some BAD language. Bad translations. Very confusing. They mention "must" have vapour barrier at the top (no mention of plywood subfloor) and then they mention the "foam underlay" and that over concrete it MUST have vapour barrier over concrete (and mentions the fact that many foam underlays can be a 2-in-1 or 3-in-1 product).

It sounds like the install instructions are for a product that does NOT have the foam underpad....because the mention foam underlay (foam on foam is known to be squeaky).

Hmmmm. Smacks of a bad translation. The National Wood Flooring Association notes that "manufacturers installation and maintenance instructions will override the NWFA guide to Best Practices". But the NWFA never had to come up against the bad translations we see today.

I would say the manufacturer did NOT pay someone enough to translate this document properly. It is confusing to say the least (I've had to do my fair share of translation so that installations are done "properly" and not how the manufacturer's "translator" thought it should read).

I would say, "Don't do it." But I am not the manufacturer and I will not hold the warranty for you. The wooden subfloor (and not all OSB likes leveling compound...just so you know) is always a wood subfloor...no matter how much concrete you pour over it. Wood is wood is wood is wood.

Just for fun, I would take some of that stuff that is being removed and hold on to it (maybe 2-3 boxes worth). I would click it together over the OSB WITHOUT the vapour barrier and see if you here the squeaking and the crinkling. I bet you won't here a thing.

And sometimes these drop locks (drop it and then knock it into place) can be a bit touchy...and sometimes (like all things) they can be noisy...all by themselves. Take those 2-3 boxes of "throw away" planks and try them out where you live. See if you can get them to make noise. See what it was that caused the noise.

Sometimes it is the joint itself...sometimes it is foam on plastic...and sometimes it is the wobbly subfloor causing all that movement. I would check it out - just for fun.

The noisy moisture barrier is only an issue in certain areas of the floor, in about 8 small areas over 1300sqft. They're all areas where the floor gives excessively because it's not flat. Most of the areas are silent regarding the moisture barrier so I think it will be okay once it's properly leveled.

We do have an extra box of flooring and the planks are silent at the joints so the cracking joints must also be due to an unflat subfloor.

You're scaring me about OSB not liking the self-leveler! I contacted Mapei today and they sent me a list of the specific products that must be used (primer, synthetic mesh, and leveler) so we will make sure the correct steps are taken. If they can't get it right they'll just have to figure something else out. We are concerned about how much height will be added all over because I can't imagine they will want to pull out our kitchen cabinets and counters...but they have to be able to slide the dishwasher in/out when the floor is re-leveled...

Sigh....this is why OSB can cause problems down the line. There are high-end OSB products that will accept anything that regular plywood will accept (they are as expensive or more expensive than plywood) and then there are others that are OK with SOME STUFF (a little cheaper than regular plywood) and then there is the bottom of the barrel type OSB which is SUPER cheap and has issues with staying together let alone self leveling being added.

The OSB can be covered. Yep. A new deck of regular plywood can be put down if need be (your builder won't like it because it DOUBLES his subfloor costs...which is why they go cheap OSB in the first place).

The guys at Mapei are the nicest, coolest science geeks (and I say that with the utmost love and warmth in my heart) you will ever meet. They care and are passionate about what they do. If they have given you a list of things...then you are well prepared to move ahead.

As for the kitchen....most laminates should not go into kitchens. I've read the specs on this laminate. They advertise the water and moisture resistance. Good. If they raise the floor height too much (very, very, very possible) I would look to a sheet material in the kitchen - such as sheet vinyl. I know it isn't what you want...but it will "fix" the issue without a massive renovation on your new build.

I would "think about it". I would go sheet vinyl shopping - just in case this occurs. It hurts NOTHING to be prepared. Nothing. Just a bit more time in the shops. Find 1-2 sheet vinyls in stone/tile patterns that would work with your laminate/kitchen stuff and then relax. You can relax knowing that you have a back up plan should this go sideways....preparation for a possible event will keep you calm and feel like you are in control.

Good luck.

Thanks, Cancork.

Before they start working on it we are requesting a detailed list of what they intend to do, how they're doing it, etc. Our builder is in the loop of all of this as well and everyone is being cooperative.

Under no circumstance will we accept sheet vinyl anywhere. This mistake is not our problem and ultimately if they need to remove cabinets that is their problem. We have somewhere to stay while they tear up the floor so a timeline isn't a big issue. Right now they said it would take 3-4 days but between removing baseboards, letting the self-leveler dry, cutting and installing the new floor, reinstalling baseboards, etc I'm guessing one week. These are details we will get in writing before work begins.

@Lisa G

If you spoke to Mapei im sure they told you self leveler over a wood structure is risky. especially when using it to level. There are very strict minumum or "feather edge" concers with self leveler and if by saying " mesh " you are likely referring to " 2.5 Lath (synthetic or galvanized) its very tough to terminate that with a feather edge. It usually requires a deeper pour or Lift to encapsulate the lath and meet mapei's mimimum thickness requirements " While terminating leveler anywhere in the field of the floor. ( or perhaps they are referring to bridging board seams with sheet mesh as well..) mapei does make a few different levelers as i recall.

Regardless. You have a bigger issue in either busted joists, crowned cantileavers, or a sil plate, support beam issue etc. and that needs to be dealt with properly FIRST. simply jacking the floor up at low spots im affraid is not always the fix.

At times we have to completetly remove all subflloring down to the joist themselves and plane down joists, cantieavers etc while also sistering and raising other settled joists. This can also involve failed footings, CMU issues rotted sil plates etc. ( i am not looking at youre homes structure here).

Everything Cancork said about Mapei and OSB OSB OSB is very true and remember that self leveler used over a deflective substrate still requires a properly installed and deflection rated substrate to work and it does not like feather egdging at all over wood as it is a great point of possible cracking/bonding/failure.

I would suggest getting a lot of stuff in writing and document things with a lot of pictures of both under the home @ post/beams/joists & cantileavers and sil plates/foundation/cmu.

In wood structured homes the best subfloor/substrate you can apply is EXP1 APA exterior glue plywood, double layered at 1/2 or 5/8" layers cross grain, glued and screwed and this is likely what mapei will tell you. For floating and wood floors you can at times get by with a single 3/4" layer (structure permitting) as well you need to be sure all and every board seam being properly perimiter and cross blocked.

Self leveler is great in the right scenario, but remember its not being used to add strength ,(the lumber and plywoobut are) but the leveler is only there to level out an ALREADY sound and properly prepared subfloor/substrate and it is ADDING more WEIGHT to youre joist system and substrates deflection..

sorry for the long winded typos, a subject near and dear to every flooring guy/gal!!! My free advice learned over years THE HARD way, the kick in the shins hard way!!. The thing about what we do is we learn immensly by failures, and tearing apart homes to see exactly what works over time and what doesnt. as well as staying on top of constantly changing industry standards and practices. Cancork included.

Perhaps you have an excellent builder, still tread lightly with levelers over lumber and try to find the structural cause of the out of level floor.- best