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  1. #41
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    Listen to IdahoJim's advice. Its obvious he knows how things work in the contracting business, and his statement that money is your only leverage is a universal truth in construction work.

    A number of years ago, we furnished one of our cranes to pour the 3rd floor on a local building owned by the city. The GC decided to save money by having a crew of his laborers place and finish the mud. When they finished, they had 180 yards of concrete that woulda passed for a motocross track if you'd spread a little dust on top.

    They had to let it cure for 14 days, and then we had a crane and tractor/trailer on the job for almost a month as they'd jackhammer areas to expose the rebar, hook chokers into those areas, and saw out rectangles about 6 x 12 till it was all gone and they could start over. On the 2nd try they decided it was worth the money to hire a finisher

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    Jim, the contractor pays the guy who did the floor. I don't even know who that was. I pay the contractor every 15 days.

    Neil, I spoke with the contractor about the floor finish (on the original structure) thinking I would want a finish smoother than a "broom finish". But he suggested not to get too smooth due to a danger of slipping especially when wet with water or oil. So I backed off on that. But a smooth finish would be nice for the reasons you stated. Also a Gray/white finish would brighten up the shop but I decided, on the oirginal structure, I didn't have the money to "paint" the floor.

    Bruce

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    We own a curb and gutter business and we do some driveways and a few floors. i could see a 1/8 inch over a little area but not let that be. we would have removed the slab and re done it, if it one of are pours. i would place money that A over worked the con and it caused it to drop or B that they screwed up when they screed it. almost every floor we ever do is either fresnos it or power trowel it. we only broom sidewalk or drive ways. If the floor is broomed the only way to make it come close to clean is a shopvac. Their really is not over 1300 dollers in concrete in it. if its just a 5 inch floor. I would make them pay it.

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    Quote Originally Posted by BruceC View Post
    Jim, the contractor pays the guy who did the floor. I don't even know who that was. I pay the contractor every 15 days.

    Neil, I spoke with the contractor about the floor finish (on the original structure) thinking I would want a finish smoother than a "broom finish". But he suggested not to get too smooth due to a danger of slipping especially when wet with water or oil. So I backed off on that. But a smooth finish would be nice for the reasons you stated. Also a Gray/white finish would brighten up the shop but I decided, on the oirginal structure, I didn't have the money to "paint" the floor.

    Bruce
    Sent you a PM, Bruce. Since the general selected and paid the floor guy, you deal with the general...he's responsible. Dealing with the floor guy is the general's problem. Contact the ready-mix plant and find out how much the material cost. Deduct both material and labor for the floor, from the amount the general bills you, until the situation is resolved. See the PM for more info. Don't let the general tell you it's between you and the flatwork guy.....the general is responsible to you. The flatwork guy is HIS problem, he chose him, and pays him.
    Jim
    PS...by the way, your floor has about 15 or 16 cu.yds. in it. Around here that would cost about $1,900 for a 3,000psi mix

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    Oh brother, let's get more specific. Do you have a specification for concrete flatness in your house plans???

    I know I didn't when I paid for a concrete basement floor here and I bet you didn't either. So I ask again, who are you going to hold accountable? The only way 5/8 across that slab will be unsatisfactory is per the house plans, right?

    Funny thing, if it hadn't rained you wouldn't even have an issue right now.
    is this a real problem or not?

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    Quote Originally Posted by IdahoJim View Post
    PS...by the way, your floor has about 15 or 16 cu.yds. in it. Around here that would cost about $1,900 for a 3,000psi mix
    Probably over two grand where OP is. Where I am in CA, a 3,000 psi mix is about $140/yd ($2,240 for 16 yards). Placed concrete is about $5/sq ft, not including site prep or steel. Total installed cost (incl prep, steel, etc) for garage floor type slab around here is near $10/sq ft.

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    Quote Originally Posted by JL Sargent View Post
    Oh brother, let's get more specific. Do you have a specification for concrete flatness in your house plans???

    I know I didn't when I paid for a concrete basement floor here and I bet you didn't either. So I ask again, who are you going to hold accountable? The only way 5/8 across that slab will be unsatisfactory is per the house plans, right?

    Funny thing, if it hadn't rained you wouldn't even have an issue right now.
    is this a real problem or not?
    It is a shoddy job period, if he can live with it fine, and he may have to, but I would do a little squawking about it now if it was me. My guess is the finisher got on there to quick with a power trowel, you can dig a hell of hole with one in a little bit.
    James

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    Quote Originally Posted by BruceC View Post
    Jim, the contractor pays the guy who did the floor. I don't even know who that was. I pay the contractor every 15 days.

    Neil, I spoke with the contractor about the floor finish (on the original structure) thinking I would want a finish smoother than a "broom finish". But he suggested not to get too smooth due to a danger of slipping especially when wet with water or oil. So I backed off on that. But a smooth finish would be nice for the reasons you stated. Also a Gray/white finish would brighten up the shop but I decided, on the oirginal structure, I didn't have the money to "paint" the floor.

    Bruce
    Yes, all understandable. Sorry if I came on a little strong.

    Paint/sealer aids proper curing and resultant strength, too. The contractor wouldn't want to polish the slab-it's way more work and makes the construction site more dangerous. But once construction is done, will you frequently have water or oil spilled on the floor? I'm guessing not, but if so, slightly rough is a good choice. As you've noted, you're the one who'll have to live with it for years, while the contractor won't.

    Neil

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    My shop floor was poured with two inches of drop from front to back. If water gets under the door I have two inches standing in the back until I pump it out. Seems to be normal workmanship where I live.

    I see three options:

    1. Call LaFarge and talk to them about an Agilia overlay. This stuff pours like a thin milkshake, self levels, and is stronger than the base concrete. Agilia doesn't even need finishing so you can do it yourself.

    2. Fight with the contractor until they wear you down and you give up. They are better at this than you or they wouldn't be contractors. At best you might get them to pay for option #1.

    3. Cut a hole in the middle of the pond. Install a fake drain and tell people you intended it to be this way.

    I'm going for option #1 as soon as I can figure out where to put all my equipment during the process.

    Doug

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    PAYING FOR THE JOB IS LEGAL PROOF THAT YOU ARE SATISFIED WITH IT. If you aren't happy with it,don't pay for it,an take it to small claims court. Trouble is,can they get at the floor to repour it when the building has been built around it?

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    I agree it sucks , why not have the GC guy level it with one of the products mentioned and expoy paint it on his dime.

    Jay

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    You didn't say, how this is hurting you? It would be a cold day in H when I put something on it to level it. It will never look right or like the rest of the floor. I will agree 5/8" is a little much. Will you have water in the building often? Was the floor supposed to be level or was it supposed to be poured on a grade. No body or company can pour concrete dead level. If it has to be fixed, saw a square section out that encompasses the low area and repour. If flatness was not specified in the contract there may not be anything you can do legaly although most contractors would try to do something. If you go to court the other sides lawyer will ask to see the compaction testing of the entire site from an acreddited testing company. You will have to prove the whole thing didn't settle on its own. We know it didn't but it is hard to prove. I would ask Bob Campbell on this machinist forum. Have you noticed, everyone is a concrete expert. lol Kenny

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    Default What has the inspector/engineer determined?

    The city inspector has the engineer who reviewed the blueprints for support.

    They can review the documents and state weather or not the specifications of the project requires the slab to be flatter than it is.

    If the slab does not meet this spec, then it is not passed and there is no obligation to pay for it, the building process may halt until fixed, or allowed to continue, either way, you need to know what the actual requirements are, the inspector and building department can show you.

    The inspector works for the city, true, but you pare paying the city for their services, their job is to protect your interests from the contractors.

    If they state it is not correct, then the contractor cannot force you to pay until it is done correctly, IE the inspector passes it.

    If it is too costly or impossible to re-do, then the contractor must present the remidy to you, and it must be approved by you and the engineering folks, and be completed at their cost.

    And if you tell the inspector that you are not satisfied with a big pond in the slab, then they may be less reluctant to pass the inspection, or more willing to revise an already cleared one.

    Now if they state that everything is within the specification of the engineering, then you have more of a workmanship issue, good luck.

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    However, consider this. The "concrete contractor" may be nothing more than an unemployed cement finisher who owns a power trowel and a pick-up truck, and hires illegals as day labors. When the city inspector insists the floor won't pass inspection and must either be leveled or come out, the "mud guy" will simply disappear. If you pursue him, he declares bankruptcy.

    Meanwhile, back at the ranch, after the inspector gets involved, he now has a hard-on for whoever called his initial inspection into question, and now insists the floor be fixed before he grants an occupancy permit. Who's going to pay for this work now?

    The time to prevent problems like this are before they are "cast in concrete", so to speak. That's why big jobs have on-site inspectors, to catch this stuff as it happens. Little guys are supposed to be protected by having licensed and bonded contractors do the work, but it sounds like there is no clear agreement who actually hired the contractor who did the floor. Better determine exactly who ultimately has financial responsibility for this part of the job before stirring up the hornets nest.

    Dennis, who did this sort of stuff long ago.

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    Never thought of checking my shop floor for flatness untill I read this post. Just went out and checked and it is within 1/8" so I guess I got lucky. Peter

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    Quote Originally Posted by Tony Quiring View Post

    The inspector works for the city, true, but you pare paying the city for their services, their job is to protect your interests from the contractors.
    I am curious where you get this notion that inspectors are to protect consumers from contractors. Do you have some experience with this? I was a GC once, and have some other related experience, and I have never seen an inspector act in this sort of role. I know my local inspectors from being a customer, and I'm pretty sure they'd laugh if I suggested this to them.

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    Thanks again to all who gave input and suggestions about my shop slab floor "birdbath". Thanks to Jim for all his time.
    I measured a birdbath depth of 5/8" and the contractor, last week, measured it dry at 11/16". I think he strung a line across it to measure. He said he will measure again with a straight edge. Beyond that nothing has progressed. He has multiple jobs going on and it rained all last week. He really can't fix the dip (if that's what happens in the end) until they finish putting up the beams holding up the roof because of all the braces in the way.
    With my wife prodding me from behind, I indicated to the contractor I didn't feel comfortable paying the full two week payment ( I pay every two weeks for labor and material used) and we agreed for me to hold back $3000 until the issue was resolved.
    I have continued doing research on the internet and have found a way of measuring flatness call "F" number. Following is a definition and some references if anyone is interested. I don't think it is directly useful to me (unless I paid someone to measure the dip for me using this system), but interesting. A number of articles suggested trying to measure birdbaths with a straight is not reliable and that they have a special tool to measure for the "F" number.

    "1. What are F-Numbers?

    The F-Number System is the American Concrete Institute (ACI 117) and Canadian Standards Association (CSA A23.1) standard for the specification and measurement of concrete floor flatness and levelness. F-Numbers replace the familiar "1/8th inch in ten feet" type specs that had proven unreliable, unmeasureable and unrealistic. "

    The Face Companies - The 40 Most Asked Questions about F-Numbers

    ASCC position statement #7: birdbaths on concrete slabs | Concrete Construction | Find Articles at BNET

    Concrete - Slab Flatness and F-numbers

    http://www.ltrc.lsu.edu/tec_07/prese...imitations.pdf

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    One of the web site:

    ASCC position statement #7: birdbaths on concrete slabs | Concrete Construction | Find Articles at BNET

    is the "position statement" from the American Society of Concrete Contractors (ASCC) concerning "Birdbaths on Concrete Slabs". This position statement was given to me by my contactor. I contacted the ASCC Technical Hotline asking for more information on the issue. In his reply he the technical director of the ASCC indicated there are 5 concrete floor surface classifications as listed in the Table below. The description of "conventional" and "moderately" flat floors are:

    "Floor surfaces in the CONVENTIONAL category can be routinely produced using strikeoff and finishing techniques that include no restraightening operations after initial strikeoff. This classification of floor surface is generally not compatible with floor coverings such as carpeting and vinyl flooring. Conventional floor surface tolerances are appropriately applied to areas such as mechanical rooms, nonpublic areas, or surfaces under raised computer flooring or thick-set tile.

    The MODERATELY flat classification of surface tolerances will routinely require the use of float dish attachments to the power float machines or some restraightening of the concrete surface during finishing operations to consistently achieve flatness requirements. The moderately flat surface can routinely be produced by using a wide bull float (8 to 10 ft) to smooth the concrete and a modified highway straightedge."

    The "gap" is measured under two high spots using a 10'straight edge. I tried to include a diagram of this but couldn't get it to show up on this Thread.

    I am not sure this is overly useful for one large dip as opposed to multiple undulations in the same amount area. But at least it is a standard in writing.

    Below is suppose to be a TABLE of information but I couldn't get it to transfer to this thread so I improvised using (----) to separate the colums so it sort of looks like a TABLE.

    "Manual straightedge method" of measuring extent of birdbaths:

    Floor Surface--------Maximum gap-------Maximum gap
    Classification------- 90% compliance----100% compliance

    Conventional-----------1/2 inch---------------- 3/4 inch
    Moderately flat---------3/8 inch----------------5/8 inch
    Flat----------------------1/4 inch----------------3/8 inch
    Very flat-----------------N/A-------------------- N/A
    Super flat---------------N/A---------------------N/A
    Last edited by BruceC; 03-29-2011 at 06:51 PM.

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    Thanks for the update, Bruce. I didn't want to get into the "F" number business, because it is fairly complicated system to understand, and, for most shop floors the straightedge method works well enough.
    I'm glad the contractor understands there is a problem. Looks like you'll get something in the way of compensation for a lower-quality product.
    That "conventional" floor spec is for floors that see little foot traffic...mostly slabs under equipment, and as it said... slabs that are under the actual walk floor surface, like in computer rooms, etc. Those floor also, usually, don't have a great finish...maybe broom, or once-over with a hard trowel.
    The lowest spec, for a floor that is used, as is, with no floor covering, is what used to be called a class 'C' floor, and was 3/8" to 1/2" under a 10' straightedge. Most shop floors were assumed to be a class 'B', which was 1/4". Class 'A' was 1/8", though it is now widely accepted that few floors that were accepted as within 1/8" actually were....they just couldn't measure them accurately enough to know, and many class B floors were accepted as class A simply because they worked OK, and nobody cared enough to really check.
    We concrete contractors were warned by ACI, once really accurate measuring devices were produced, that we should be careful about accepting contracts speccing 1/8" because it was a difficult spec to meet, and that just because our previous floors were accepted as meeting 1/8" didn't mean they actually did. This whole floor flatness subject has turned into a "nest of snakes" since high-tech came into the concrete industry. They'll be arguing about it for years IMHO.
    On your floor....it may meet the "flatness" spec, as the 5/8" dip is over a fairly large area, but would probably fail the "levelness" spec because of the 5/8" depression from level.
    That's why there are two numbers in the 'F' system...one for flatness, and one for levelness.
    Jim

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    Core a hole in the center, install a drain, poof, problem solved, now that area is designated for drainage! lol

    Good luck with the situation, worst case, it's not a huge deal, but best case, it gets resolved and is more of a bird wading pool vs a bird bath.


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