Concrete Driveway - Sealing

[Tubby2]

Hi guys, I had my driveway poured 2 weeks ago, a colour thru oxide concrete and from the first day I noticed a couple of white patches have come thru. We have a broomed finish and the patches look like the concretor has dipped the broom in a watered down white paint and done a couple of lines. They start from the middle of the driveway and get fainter closer to the edge.

I have spoken to a couple of people about this. The original concretor offers no explaination for it and just says to colour seal it and it will be fine....of course it will, me covering up your dodgey work!..... I spoke to a couple of places that sells sealer and they recommend just putting clear sealer on it (which I had planned to do) and that will 'disolve' the white lines. Some one else descriped it as flouresence coming thru or salt from the sand coming up and to clean it with a light acid wash.
I bought some Hydrochloric acid diluted it and tried scrubbing the lines. The white pateches did not dissapear but I did start to notice the concrete starting to wash away and the aggregate coming through. I gave the acid idea away then.

I was told the clear sealer would make the driveway look the same as when its wet. Unfortunately when the driveway is wet the lines are still very much visable, not as much when dry, but still stick out like dogs balls.

Can anyone offer any solutions or will I have to colour seal it.
The olny problem I have with colour sealing is that firstly I have already bought the clear sealer and secondly putting a colour sealer on defeats the purpose of spending $600 on coloured oxide.

Any ideas?

Cheers

[dazzler]

Is it lime discolouration coming through similar to when you have new bricks laid

[Tubby2]

Not sure what it is, I do know that it doesn't come off with hydrochloric acid


I'll take a photo or two, Not sure if that will help at all but it cant hurt.

Cheers

[dazzler]

Photos good.

Tonight a concreter or brickie should be online so check back.

Maybe give it a few more weeks to completely dry and then see how it is.

best of luck

[Black Ned]

Whatever the problem - the tradesman should be made to fix it. He should have insurance to cover his work. Once you get involved with you own methods and try and fix it you are on your own. think carefully before attempting any more fix ups yourself.

[Bleedin Thumb]

It doesn't sound like salts to me because salt should scrub off when new - dont know who told you to give a coloured concrete slab an acid wash!

.. if the batching plant is real close to your home maybe it wasn't mixed well enough.. or did they add anything to the concrete to make it go off slower or quicker?

[Pulse]

http://www.dectech.com.au/PDF_Files/ColThru_guide.pdf


They say an acid wash is OK, It surprised me too. Sounds like laitance then?


Cheers
Pulse

[patty]

so the oxide was mixed into the concrete when poured? Was it mixed prior to delivery? or was it "thrown on" and trowled in? I guess only being 2 weeks old it was not a hot day most likely windy? did they wet the area that is dis-colured to prevent it going off prior to finishing? If you have hit it with acid and it has come off it to me and I am no expert, but have done alot of concreting, is that the oxide has not bonded into the concrete surface when finishing, possibly because it was too dry , and you thinking it is someting else like salt leaching through to the surface, have basically bleached the surface with the acid removing the colour even further...

Now that you have tried to fix this with the acid I dont like your chances of "coming back at the concretor" and arguing the point about the initial poor work...

The sealer coat will definitley help with the overall colour appearance but with the area that you have taken back to exposed agg the oxide will have to be re-mixed and applied over the existing cement possibly through a spray on application and tried to blend as best as possible then finish with a colour seal over it... Just dont be too heavy handed with the sealer as I have seen some Diy Jobs that are absolutley terrible put on too much and you get this what i call " turtle shell finish on top" looks very crazed"

good luck

[Tubby2]

so the oxide was mixed into the concrete when poured? Was it mixed prior to delivery? or was it "thrown on" and trowled in? I guess only being 2 weeks old it was not a hot day most likely windy? did they wet the area that is dis-colured to prevent it going off prior to finishing? If you have hit it with acid and it has come off it to me and I am no expert, but have done alot of concreting, is that the oxide has not bonded into the concrete surface when finishing, possibly because it was too dry , and you thinking it is someting else like salt leaching through to the surface, have basically bleached the surface with the acid removing the colour even further...

Now that you have tried to fix this with the acid I dont like your chances of "coming back at the concretor" and arguing the point about the initial poor work..."

good luck

The oxide was mixed at the plant which is about 20mins away. Your right it was a friggin freezin day and no they didnt wet the area before putting the concrete down.
I was told to give the drive a 'light acid wash' by 2 people. The first was from CCS the people that supply the oxide and the other was from the guy at "Sydney Wholesale Concrete Supplies" or something like that at Wetherill Park.
The aggregate is only just coming thru and if you didnt get down on your knee's you would know about it. I stopped cleaning as soon as I saw it.

Photo's attached below

[MrFixIt]

Hi

After seeing those photos there is NO way that is salt or leaching or ANYTHING else other than poor workmanship. The colouring put on the top of the concrete has been "brushed" away and/or made MUCH to thin.

The guys doing the work SHOULD have been able to see the problem WHEN it occurred and they should have fixed it THEN.

It is unlikely that you will be able to "repair" this, AFAIK there is nothing other than completely PAINTING the driveway that can hide/remove the light marks.

Either the concretor has to redo the driveway OR at least pay (materials AND labour) to have the driveway painted. If the driveway IS painted, this means you will have to repaint it very few years to keep it looking good.

[Bleedin Thumb]

Yes I agree with Mr fix it as far as not salt, but I don't know if the problem is with the concretor or the concrete supplier.

If its the later I bet there is a disclaimer that says any additives that are requested by the client are not guaranteed etc etc..

The concretor will blame the concrete and oxide and the concrete supplier will blame the concretor or the oxide manufacturer which leaves you up a certain creek.

If you can't live with it.... I recon it will fade into insignificance within 2 years... try Nutech paints. I think there paving paint is guaranteed for 10 years.

Sorry I can't see you getting a result from the concretor...unfair as it may seem, unless you want to spend big bucks on lawyers.

[Tubby2]

Thanks for the feedback guys. I'll wet the driveway again and take another look at it to see if the clear sealer would lessen the mark (as I was told clear sealer looks similar to the concrete being wet). If all else fails colour sealer it is.

The colouring put on the top of the concrete has been "brushed" away and/or made MUCH to thin.

The oxide was not put on top after the pour, it was put in the mix at the concrete plant and was mixed in on the 20min drive to site. Apparently 20mins is more then enough to mix in the oxide.

The concretor did offer to seal it for me if I provide the sealer. I may just take him up on that.

[patty]

Now that i have seen the pictures it does look as though he has used a broom maybe with a light coat or residue of cement on the bottom of the bristles as everyone has said it certainly

[patty]

Now that i have seen the pictures it does look as though he has used a broom maybe with a light coat or dried residue of cement on the bottom of the bristles or maybe even the broom being too wet when finishing and it has taken that section of colour away on brooming it off...

Mate if he has offered to apply the seal coat let him go ahead and do it ask him does he think it will hide the imperfection in the slab before e applies it just to get an answer? And if it does not ask him how he is going to fix it throw it back on him!

[Bleedin Thumb]

I think Patty may be on the money there. It has something to do with the broom finish it would seem, maybe you do have a good case against the concretor.