Low Spots in Concrete Floor

[stomperxj]

Yes it's another "low spots in my floor" thread. I have searched and read as much as I can but Haven't really decided what to do about this. I thought I'd throw it to you all and see what kind of suggestions/comments I get.

First off I'd like to admit the mistakes I made with the concrete contractor I chose-

-I picked the lowest bidder
-I paid him as he went
-I paid him more than the contract stated
-I believed him when he said he would come back to fix things

The concrete contractor talked a big game and then showed up and proceeded to screw up a lot of items on my shop-

-felt not installed with chalk line, he measured from the top of the stem wall
-hold downs at the garage door installed on the wrong side of the stem wall
-wrong concrete mix used for the pad (3000psi instead of code minimum 3500psi)
-bad low spots

Yeah I pretty much screwed myself by paying him as he went... anyway on to the pics and hopefully some good discussion.

Below are pics of 2 of the 3 bad spots. These spots are all roughly the same size (about 4ftx3ft). the pics show the worst area/middle of these spots... about 5/16-3/8" over 3ft which is horrible.

I have read about some concrete patchs that are 8-10k psi like the Garon stuff. I have looked into having someone diamond grind the higher spots. I'm leaning towards the patch stuff because I think the grinding would make it worse...

Any comments or suggestions?

Thanks!
Jess

 

[77thor]

I've got a low spot in one corner of my garage and I plan to use this Rapid Set TRU Self Leveling product once the weather here warms up.
http://www.ctscement.com/TRU.asp

The problem is that so far I have not been able to find it locally.

 

[pauloman]

cements like the one above generally don't feather out, bond well, and tend to crack. Still this product claims otherwise. In commercial settings epoxy ($$$$) is used.

 

[CNGsaves]

Yes it's another "low spots in my floor" thread. I have searched and read as much as I can but Haven't really decided what to do about this. I thought I'd throw it to you all and see what kind of suggestions/comments I get.

First off I'd like to admit the mistakes I made with the concrete contractor I chose-

-I picked the lowest bidder
-I paid him as he went
-I paid him more than the contract stated-I believed him when he said he would come back to fix things

The concrete contractor talked a big game and then showed up and proceeded to screw up a lot of items on my shop-

-felt not installed with chalk line, he measured from the top of the stem wall
-hold downs at the garage door installed on the wrong side of the stem wall
-wrong concrete mix used for the pad (3000psi instead of code minimum 3500psi)
-bad low spots

Yeah I pretty much screwed myself by paying him as he went... anyway on to the pics and hopefully some good discussion.

Below are pics of 2 of the 3 bad spots. These spots are all roughly the same size (about 4ftx3ft). the pics show the worst area/middle of these spots... about 5/16-3/8" over 3ft which is horrible.

I have read about some concrete patchs that are 8-10k psi like the Garon stuff. I have looked into having someone diamond grind the higher spots. I'm leaning towards the patch stuff because I think the grinding would make it worse... Any comments or suggestions? Thanks! Jess

Have you had "Come To Jesus" meeting with this concrete guy?? Provide him written complaint of the poor workmanship and request refund of overpayment on contract within 10 days. See how this shakes out if HE WILL PAY for poor work . . . you should not be paying for this fix!!

Worst case, take him to small claims court. Document all your interactions along the way with emails and record your phone calls.

 

[stomperxj]

Have you had "Come To Jesus" meeting with this concrete guy?? Provide him written complaint of the poor workmanship and request refund of overpayment on contract within 10 days. See how this shakes out if HE WILL PAY for poor work . . . you should not be paying for this fix!!

Worst case, take him to small claims court. Document all your interactions along the way with emails and record your phone calls.

I actually tried to get him to fix it. He said he would initially, then stopped communication about a month ago. His main argument is that I "didn't ask for a flat floor". I have everything documented, all receipts, contract etc... I was trying to figure out how expensive this fix would be and if it was worth it to try and fight for it. If I get a judgement against him then I have to get him to pay me. Not sure how hard that would be as Ive never been to Small Claims before. I dont want him doing the work either. I'd want someone else to come in and fix it. Small Claims is a very good option though. I just need to know the best way to fix these low spots and get a cost on it. Then I can decide if its worth taking him to court....

Thanks for the comments so far-
Jess

 

[TDabney]

I wish I had some easy answers for you... but I don't. I have a similar thread about the floor in my shop here: http://www.garagejournal.com/forum/showthread.php?t=193459 although my concrete slab was pre-existing, not new.

What I would like to ask of this discussion is this: what are realistic expectations to have when it comes to pouring a new slab floor? Jess's slab as described in this thread would be below my expectations... but I don't pour concrete for a living. Is there a standard unit of flatness that one could have in a contract that is measurable - and if the end product (the slab) meets it then great, and if not, then it needs to be fixed? Is it 1/4" over 10' or 1/8" over 10'? I have no idea what is realistic to expect or how to measure flatness?

I ask because as I ponder removing the existing slab in my shop (1,100 sq.ft.) and pouring a new one, one of my fears is that the new one wouldn't be any better! I don't know if I have realistic expectations or not...

Tom

 

[LegacyIndustrial]

Jess:

When you say low spot...
How bad are we talking? 1/32", 1/64"??

A "perfectly" flat floor is difficult to achieve. All floors have a little bit of undulation in them.

In response to the patch it would have to be polymer/urea based or it will be weak in one or more departments.

We make a good one, MG-krete is said to be good as well although I have never used.

 

[stomperxj]

I wish I had some easy answers for you... but I don't. I have a similar thread about the floor in my shop here: http://www.garagejournal.com/forum/showthread.php?t=193459 although my concrete slab was pre-existing, not new.

What I would like to ask of this discussion is this: what are realistic expectations to have when it comes to pouring a new slab floor? Jess's slab as described in this thread would be below my expectations... but I don't pour concrete for a living. Is there a standard unit of flatness that one could have in a contract that is measurable - and if the end product (the slab) meets it then great, and if not, then it needs to be fixed? Is it 1/4" over 10' or 1/8" over 10'? I have no idea what is realistic to expect or how to measure flatness?

I ask because as I ponder removing the existing slab in my shop (1,100 sq.ft.) and pouring a new one, one of my fears is that the new one wouldn't be any better! I don't know if I have realistic expectations or not...

Tom

Tom-
Here's a link to ACI guidelines for conventional floors. It seems to me that 1/8" over 10ft is not out of the question at all. Conventional floors should be an Ff of 20.2 which is the upper left on the linked chart:

http://www.concrete.org/FAQ/afmviewfaq.asp?faqid=26

Jess:

When you say low spot...
How bad are we talking? 1/32", 1/64"??

A "perfectly" flat floor is difficult to achieve. All floors have a little bit of undulation in them.

In response to the patch it would have to be polymer/urea based or it will be weak in one or more departments.

We make a good one, MG-krete is said to be good as well although I have never used.

Well the pictures pretty much show it. the low spots are 5/16" plus in some areas, the others are closer to 1/4". all are over a span of no more than 36-48"

Can you epoxy coat over the top of the polymer/urea patch?

 

[cbracer]

I've got a low spot in one corner of my garage and I plan to use this Rapid Set TRU Self Leveling product once the weather here warms up.
http://www.ctscement.com/TRU.asp

The problem is that so far I have not been able to find it locally.

Note you will have to apply a topping over this, as it is not wear resistant. Tile or something?

 

[LegacyIndustrial]

Tom-
Here's a link to ACI guidelines for conventional floors. It seems to me that 1/8" over 10ft is not out of the question at all. Conventional floors should be an Ff of 20.2 which is the upper left on the linked chart:

http://www.concrete.org/FAQ/afmviewfaq.asp?faqid=26



Well the pictures pretty much show it. the low spots are 5/16" plus in some areas, the others are closer to 1/4". all are over a span of no more than 36-48"

Can you epoxy coat over the top of the polymer/urea patch?

Yes, post application you need to grind very smooth, prime and then apply topcoat.

 

[ConCretin]

What I would like to ask of this discussion is this: what are realistic expectations to have when it comes to pouring a new slab floor? Jess's slab as described in this thread would be below my expectations... but I don't pour concrete for a living. Is there a standard unit of flatness that one could have in a contract that is measurable - and if the end product (the slab) meets it then great, and if not, then it needs to be fixed? Is it 1/4" over 10' or 1/8" over 10'? I have no idea what is realistic to expect or how to measure flatness?

Floor flatness on commercial jobs is generally specified using whats referred to as Ff / Fl, which is basically a measurement of localized bumpiness and overall levelness respectively. The problem is most residential contractors won't know what your talking about or how to achieve it - plus you need special equipment to test the floor.

The old standard is to measure the space under a 10' straightedge. A good floor would show have few to no gaps greater than 1/4". An exceptional floor would be closer to an 1/8"

I wouldn't hesitate to write this spec into the contract with your finisher. This will ensure he knows what you are expecting and you've established a standard to evaluate the finished product.

 

[stomperxj]

Floor flatness on commercial jobs is generally specified using whats referred to as Ff / Fl, which is basically a measurement of localized bumpiness and overall levelness respectively. The problem is most residential contractors won't know what your talking about or how to achieve it - plus you need special equipment to test the floor.

The old standard is to measure the space under a 10' straightedge. A good floor would show have few to no gaps greater than 1/4". An exceptional floor would be closer to an 1/8"

I wouldn't hesitate to write this spec into the contract with your finisher. This will ensure he knows what you are expecting and you've established a standard to evaluate the finished product.

Ff for a conventional floor should be around 20 according to ACI which is 1/8" over 30" using the straight edge method...

So in looking at the pictures and info above, do you think my floor is "out of normal tolerance" or should I be happy with the job he did?

I read your whole thread on your house BTW... Amazing work. You seem to know a lot about concrete. I am interested in what your opinion is on my situation...

 

[stomperxj]

Bump-

Any other comments on this?

 

[stomperxj]

Bump again - I filed a small claims case against this guy. I'll report back and let you know what happens. I'm trying to get enough to have the current floor demo'd and re-poured by a reputable company-

Jess

 

[stomperxj]

Well I won my small claims case against the concrete guy. Now just waiting for a reputable company to stop by this week and give a quote to demo and replace the floor. I may do the demo myself to save some money but not sure if I want to due to being an out of shape CAD jockey

Hopefully i'll have a new floor in about a month. Then its on to insulation, sheet rock, paint, lights etc.....

 

[CNGsaves]

Well I won my small claims case against the concrete guy. Now just waiting for a reputable company to stop by this week and give a quote to demo and replace the floor. I may do the demo myself to save some money but not sure if I want to due to being an out of shape CAD jockey

Hopefully i'll have a new floor in about a month. Then its on to insulation, sheet rock, paint, lights etc.....

Sounds like good news that you "won" your small claims case !!

Does that mean you got all your money back (amount paid to schmuck) . . OR. . are you getting "Made Whole" of demo'ing the bad floor and repouring a proper floor??

I'd want to have proper floor, AND not be out any more money overall.

 

[stomperxj]

Sounds like good news that you "won" your small claims case !!

Does that mean you got all your money back (amount paid to schmuck) . . OR. . are you getting "Made Whole" of demo'ing the bad floor and repouring a proper floor??

I'd want to have proper floor, AND not be out any more money overall.

I got enough out of him to have the floor demo'd and get it re-poured by another reputable contractor based on bids I got for the small claims case. I should not be out of pocket for anything.