So I got the bid to install a couple of bedrooms with Mannington 3/8" engineered 5". After the contractor tore out the carpet and pad, I was able to check for flatness. Well, not to my surprise, the slab was off and out of spec. So I inform the lady and she says, "I don't have any money to fix it". I tell her fine, but you'll need to sign a waiver of liability, because there will be some hollow sounding spots. She agrees and I lay the floors. After completion, I was right; there are some "hollows" were the slab was low. So my question is, Outside of the flooring sounding hollow in those places, is there any other potential problem/s? It isn't flexing much because the hollows are limited to about one sq. ft. or less. I told her I could repair them for a fee with an injection kit but she says she'll just live with them and that her rug and furniture will cover most of them up. It sorta bugs me because I warned her in advance before I even got the job that slabs often need some work but that would be extra. Then she wants to cheap out and not pay me to do it right. Oh well, I least I got the waiver. Just hope she pays the entire bill.

I have walked from more then one of those jobs Gary .
That waiver of liability won't hold up in a lot of courts .
I know someone who had 3/8 solid installed over hollow spots around 5 years ago .

No other problems then the original popping .

I hear what you say Nick. The thing is, the general contractor is a regular customer and a friend. I couldn't leave him hanging. I explained the situation to him and he thought that all slabs were bad and I should factor in repairs to all slabs. I explained that would be unfair to the customers who's slabs didn't need repair and that no one can estimate what the repairs will take without seeing the concrete. He wasn't that concerned. I realize the waiver could go either way. And that many in the NWFA say it will not hold up. However, has anyone ever tested that? Does anyone know of a case that got shot down even though the contractor had a waiver? And we're not talking about a house falling apart here. There is no safety issues involved or code violations. The customer was fully warned of the possibility she may have hollow sounding spots in the finished floor, and now she does. They don't even make noise when you step on them. There's no popping sound. The only way you can find them is if you tap the floor with your knuckles and hear that hollow sound. So, in my opinion, the floor will not self destruct and should remain as it is now. Where it is adhered well, it's not moving. If it did go to court, it would be small claims and I'd put up an excellent argument that the customer was fully informed and that the customer refused to pay for the needed repairs. And since her old floors were already removed, she had to have the work done. She elected to have it done in an inferior manner and now, is living with the results. The floor is fully serviceable and usable. The only flaw is if one taps the floor in a few certain places, it will emit a hollow sound. Worst case scenario, court says I inject some glue. That's how I see it. But gotta tell ya, in 30 yrs, never went to court over quality issue. Got sued once over liability. Bogus case.

I can tell the quality of installer you are by your posts Gary . I wouldn't expect that you would have been in court for shoddy work .
I had a feeling there was a underlying circumstance for you to do the install .

Personally i think it would depend on the judge you went in front of .
My luck i would get one that just had his floors installed by the $1.00 a ft installer .

I've heard the same thing about waivers. My thought is to write up something saying ... my client requests that I disregard established guidelines and install a floor that will likely pop, feel hollow and show undulations in the surface..... I did what I could to accommodate my client and stay within her low budget. Also take a photo of the lady holding up a copy of the guidelines. I think even the Ninth Circuit Court of Appeals would rule in my favor

It depends how your waiver of liability is written.

In the waiver you have to be very specific about what has been asked of you. You then need to write the specifications pertaining to what they wish for you to do, against the grain, so to speak. Then you explain what is going to happen to the project after it is completed in that manner. Then in bold capital letters... THIS IS MEANT TO ONLY BE A TEMPORARY INSTALLATION. All temporary installations are done with the understanding that a full and complete replacement or correction to the customer's satisfaction is eminent. Any and all additional time and labor incurred. As a result, you will be billed for the additional labor as per our most recent price list.

Every time I present this waiver, the change order appears!!

Heck, the NWFA has a waiver form, so they must believe in them working.

Name one person that loves to hear those golden words, "I told you so"

I actually used the NWFA "Waiver of Responsibility" as a template for my waiver. I was pretty specific in the waiver as to what the problem was and what could and would occur if the customer chose not to have it remedied. It will have to do.

How much patch can a couple bedrooms take to fix a few low spots, really? Thats the way people will see it, and her friends as well.

My price includes one bag of patch which is a very common standard out here in CC land.

It was actually quite a few places. At least a dozen. It would easily have taken a day to deal with it. As it is, she refused and I laid the floor. Yep, there's some slight hollows, as I warned her there would be. She signed a waiver that specified there would be hollows. You cannot tell they are there unless one taps on the floor.

You ever try kerfing the backs and add weight, like that one pic with a thousand bricks??

I've gone over some incredible humped slabs as well, kerfing the backs and weighting. Couldn't realistically level it out flat due to doorways where the wood stops. They would be 3-4 inches deep just to get it flat.

Ya, I've encountered those irregular subfloors too. Never had to use enough bricks to build a house though, lol.
I am very clear to the end-user that whatever the plane of the sub-floor is, so too will be the finished product.
Generally, with some packing, and some grinding an acceptable surface can be had as long as the client isnt planning on using the floor as a pool table.

Ya, I'm involved with an inspection as we speak, The floor is well bonded, yet every big piece of furniture they have has layers of cardboard under one leg. The flooring dealer solution was to cut the leg... Seriously!
Place my straight edge on the finished wood flooring and it is 3/8 out in 6 feet, in the worst place.

So, that brings us back to the original question. Since most concrete slabs are out of spec, do we, as contractors, just figure that we will need to flatten them regardless? How do we inform the customer of the possible cost? In the bid/estimate or after we have inspected the concrete slab? Is there an "average" sq.ft. price we should use for concrete repairs?

If I'm typing up an estimate/proposal for a job I include one 45lb bucket of Planipatch as a given in the initial base price. I have not done a job yet that did not require at least a partial bucket. I explain all that to the client and then inform them that any additional buckets if needed are charged out at 220.00 (pick your own price) per bucket. The most I've had to use to date on any one job is 5 buckets. It's something you cannot accurately estimate and I believe this is a very fair way for everyone.

Usually during the estimating process, the area they want done is covered with other flooring materials, hiding what is really there to work with.

I explain it to the clients like this.

"Because I cannot see if the substrate is going to need a little, or a lot of floor preparation to prepare it to the strict requirements, of 3/16 in 10, as required by the manufacturer, It benefits you(the client) if I do all floor preparation as Time and materials @ XX.xx per hour and $X.xx per pound of portland cement patching compound. That way if it needs very little prep, I didn't charge you a "worst case scenario" flat fee per sq.ft. of $X.xx per and it take me 10 minutes, once the substrate is revealed and you feel I ripped you off. I get what I need to stay in business and you get an investment, installed to specifications and everyone is happy. If your still unsure, when you contact those listed on my reference page, ask about their experience with floor preparation".


Works every time.