We had a slab laid for our cars just a couple of months ago under the new roofed area, it was trucked in but when the mix was released onto the prepared area it was absolutely overloaded with blue metal and sand, obviously the company that was supplying it was making profits by using more of each with a smaller amount of cement, The workers had a very hard time trying to get a good finish as it would not level/smooth over and blue metal was showing through the surface all over it. It started to break down within a very short time and if we tried to hose it off the surface would break down even more and would wash away the cement/sand. It is a large area so removing & replacing is out of the question, if I was back in Australia I would use Bond crete to try to stop it breaking down but not sure if they have anything here that would do the same thing so need some help to find out what I can use/do to stop the surface breaking down. Needless to say we used a different supplier to finish the driveway with no problems and the finish is great, seeing this it is easy to see why so many buildings etc fall apart in Thailand, profits before quality.

3 minutes ago, seajae said:

Needless to say we used a different supplier to finish the driveway with no problems and the finish is great, seeing this it is easy to see why so many buildings etc fall apart in Thailand, profits before quality.

Was the second supplier same price per cubic as the first one?

You could tile the area, but as it's a large area maybe too expensive.

If it is breaking up everywhere, maybe the best is to jackhammer it up and do it again.

If you specify the concrete strength and buy it from a CPAC (I think) supplier, they will give you a sheet of paper with the concrete delivery with the specifications of the mix on, then if it fails you have them to contact.

2 hours ago, seajae said:

blue metal

I'm not familiar with that term. Why do you mean?

1 hour ago, Bredbury Blue said:

I'm not familiar with that term. Why do you mean?

Crushed aggregate (rock).

1 hour ago, Artisi said:

Crushed aggregate (rock).

Ok got it. Aggregate.

You could mortar over it

You could pour a fresh layer of concrete on top of it.

You could break it up and pour a fresh layer mixed with it.

You could break it up, haul it away, and pour a fresh slab.

You could seal it with epoxy.

23 hours ago, CallumWK said:

Was the second supplier same price per cubic as the first one?

there was a couple of hundred baht difference but not enough to explain the garbage the first one supplied, we used the first one because we like to use local businesses and they are only 100 metres away, they supplied the mix for the roads through our area and it was all good and finished well. The area is 8 x 5 metres so its a big job, we cant put another layer over it or it will cause flooding of the area around it

3 minutes ago, seajae said:

there was a couple of hundred baht difference but no enough to explain the garbage the first one supplied, we used the first one because we like to use local businesses and they are only 100 metres away, they supplied the mix for the roads through our area and it was all good and finished well.

Did you try going to them to make it right?

1 minute ago, Yellowtail said:

Did you try going to them to make it right?

Not as yet, my wife does not do arguing very well unless its with me, she tends to be submissive to other thais but I will be pushing her to lodge a complaint as the mix was just so bad

1 minute ago, seajae said:

Not as yet, my wife does not do arguing very well unless its with me, she tends to be submissive to other thais but I will be pushing her to lodge a complaint as the mix was just so bad

It has been my experience (and a lot of guys will disagree) that most Thai contractors will try to make it right.

Do not do anything until you call them out and have them look at it, they might just fix it for you, particularly if they are close by.

How many cubic meters was it?

around 4 metres

21 minutes ago, seajae said:

around 4 metres

I would talk to the contractor first and give them a chance to make it right.

Post a few photos of the worst areas

Buy large cheap rough texture tiles . Tiled over sand wash on my car port area , tiles looked so much better and easier to clean. Left it about a week before parking car on them and never had any problems with tile cracking with car weight.

On 2/3/2026 at 9:03 AM, seajae said:

there was a couple of hundred baht difference but not enough to explain the garbage the first one supplied, we used the first one because we like to use local businesses and they are only 100 metres away, they supplied the mix for the roads through our area and it was all good and finished well. The area is 8 x 5 metres so its a big job, we cant put another layer over it or it will cause flooding of the area around it

Jackhammer it up and start again

7 hours ago, wombat said:

Jackhammer it up and start again

Doesn't sound like there will be much actual hammering required

Good for next time, or as a hot tips

Pour cement samples in to plastic cups for every slabb or mix, make sure to moisture spray your cement every 2 hour/ 7-10 times a day with water while it cures for the next week, but I guess most do it only for 24 hours in daylight if ever. 

The cement samples is a good measurment of the quality later if there is anything wrong. Give them date, time and number of mix.

On 2/3/2026 at 9:43 AM, Yellowtail said:

I would talk to the contractor first and give them a chance to make it right.

Post a few photos of the worst areas

Well its worth a try , there's no way it was a deliberate way to save on costs by the supplier

sounds more like a mistake at the mixing plant maybe the cement silo got blocked or even ran out could be any number of things

There's not much else he can do , The mistake was made when "somebody" allowed the mixer truck to discharge its load , It would have looked wrong as it travelled down the delivery chute, It should have been stopped and sent back to the mixing plant ( which is probably what the previous recipient(s) did by the sound of things, it a bit late now, rather like checking ones change after leaving a shop

If he has a receipt for what he ordered It will specify a certain mix which could reasonably be expected to achieve certain strength, Its possible to test this , and probably not that expensive assuming he can find a testing lab but then what ? once the polite requests have been ignored, that only leaves threats and intimidation or legal action. The first would be ill advised and the second could be costly and take forever, and how much are we talkin about? 4 cube= 8000bt + a bit of labour? hardly worth it

Personally I'd leave it for a while let it get hammered and compacted by normal daily use once its settled and cracked to its hearts content he could think about skimming it with some expensive resin product if he can find any, or tile it with some concrete looking tiles , or he might have gotten used to it and decide to just leave it

8 minutes ago, Bday Prang said:

Well its worth a try , there's no way it was a deliberate way to save on costs by the supplier

sounds more like a mistake at the mixing plant maybe the cement silo got blocked or even ran out could be any number of things

There's not much else he can do , The mistake was made when "somebody" allowed the mixer truck to discharge its load , It would have looked wrong as it travelled down the delivery chute, It should have been stopped and sent back to the mixing plant ( which is probably what the previous recipient(s) did by the sound of things, it a bit late now, rather like checking ones change after leaving a shop

If he has a receipt for what he ordered It will specify a certain mix which could reasonably be expected to achieve certain strength, Its possible to test this , and probably not that expensive assuming he can find a testing lab but then what ? once the polite requests have been ignored, that only leaves threats and intimidation or legal action. The first would be ill advised and the second could be costly and take forever, and how much are we talkin about? 4 cube= 8000bt + a bit of labour? hardly worth it

Personally I'd leave it for a while let it get hammered and compacted by normal daily use once its settled and cracked to its hearts content he could think about skimming it with some expensive resin product if he can find any, or tile it with some concrete looking tiles , or he might have gotten used to it and decide to just leave it

Apparently, it was only about half a load, so he may have been a second/last stop, and they added too much water.

1 minute ago, Yellowtail said:

Apparently, it was only about half a load, so he may have been a second/last stop, and they added too much water.

Could be , It might also have been a part load that was leftover from the final delivery to a large job ,these are often slow to discharge as the concreting lads are busy smoothing off as they pour the last bit,

It could have started getting hard and the driver mistakenly thought adding water would sort it out , which it would have done up to a point , but it looks like that point had long passed

On the other hand maybe Somchai just forgot to add the cement anything's possible here

A couple of years ago I concreted my driveway concrete was due at 8.30am 10am still no sign so I phoned up , turns out the driver was too drunk to climb into his cab , lol

but by 11am he'd managed the ascent all's well that ends well , all part of the fun here

https://www.civilconcept.com/signs-of-bad-concrete-pour/

Guess you have to start all over, as if you do only top, it can continu lower part.

And then you are back to square one.

Bad mixture? Or drying to fast, too hot day to poor? You can hold that by covering it by plastic, so evaporation will go slower. Yes, I know it is large.

However you should go to contractor with the problem first.

It is just a car-park. 10cm on top with good wire and it'll likely be good for a long while, if the existing in not crumbling.

OP, how thick is the slab? Try hitting it with a pick...

Some pics of the worst spots would help.

it seems Seajae is not interested in his own post anymore.....

On 2/22/2026 at 7:26 PM, PJHassselt said:

it seems Seajae is not interested in his own post anymore.....

I have been trying to sort the problem out since posting, sorry if it wasnt fast enough for you, after having it checked by a few different people and the replies in here we have decided to go with tiles over the effected area, we have been given a really good price to do it all by the tiler we have used previously. I wasnt going to post an update till it was done and we could make sure it was the right solution but apparently it upset this poster who has not commented at all in this post apart from this whinge, boredom must be a real problem for them

Painting over peeling paint

1 hour ago, seajae said:

I have been trying to sort the problem out since posting, sorry if it wasnt fast enough for you, after having it checked by a few different people and the replies in here we have decided to go with tiles over the effected area, we have been given a really good price to do it all by the tiler we have used previously. I wasnt going to post an update till it was done and we could make sure it was the right solution but apparently it upset this poster who has not commented at all in this post apart from this whinge, boredom must be a real problem for them

We had a few crumbly bits, so I tiled over and it's been good for 9 years.

@seajae just remember that non-slip tiles are still slippery when wet, so make sure you pick the best tile or the least slippery tiles, not the prettiest tiles and leave a reasonable expansion gap between tiles for expansion and contraction.

I bought Kera tiles or big solid tiles to go around the pool area but SWMBO wanted some of the area to be pretty, cheaper, thinner locally available tiles. A few of the pretty ones have cracked.

23 hours ago, carlyai said:

@seajae just remember that non-slip tiles are still slippery when wet, so make sure you pick the best tile or the least slippery tiles, not the prettiest tiles and leave a reasonable expansion gap between tiles for expansion and contraction.

I bought Kera tiles or big solid tiles to go around the pool area but SWMBO wanted some of the area to be pretty, cheaper, thinner locally available tiles. A few of the pretty ones have cracked.

we bought ceramic tiles that will not get slippery when wet, they are looking great and are very solid, tiler does a fantastic job. Did take pics with my phone but are unable to transfer them as the samsung smart switch refuses to work properly