Concrete repair and paint

[DexterOz]

I am looking to repait small cracks in the concrete before i plan to repaint backyard concrete.Can you please suggest concrete repair product and application method.

Next i am going to repaint the concrete i have seen few videos on bunnings site but they have it on unpainted surface mine is already painted i am planning to give it a good wash and then repaint on that would that work. existing paint does not have any sealer or anything.

[MitchellMc]

Hi @DexterOz,

I've contacted one of our concrete paint suppliers, and the old paint will need to be removed before re-coating. As the paint has degraded to the extent of the concrete coming through, it all needs to be removed with an angle grinder and diamond disk. The issue is that the concrete needs an acid etch which will turn the paint gummy. Your re-coat needs to be done before the concrete becomes exposed.

Once the paint has been removed, I'd recommend you start by cleaning up all the cracks from any debris that might be trapped in them. Once the cracks are clean, apply Timbermate 500g Concremate Expanding Cement as per the directions on the packaging. 

Please let me know if you need further help or had questions.

Mitchell

[DexterOz]

Hi @MitchellMc,

Thanks for sharing valuable inputs.

Just so i understand correct  to fill up the concrete crack " old paint will need to be removed before re-coating"  where the crack is i need to grind that section the apply the Timbermate product as per product instructions.

Second  regarding painting the whole concrete area  i need to do re paint as early as possible "re-coat needs to be done before the concrete becomes exposed."

Thanks

[MitchellMc]

@DexterOz,

You can fill the crack as it is now with no issues. Removing the old paint is regarding repainting the whole area.

The advice I have received is that all the paint needs to be removed in order to repaint. This is done by grinding the paint off, back to concrete, for the whole concrete area. The paint supplier I have spoken to believes that your paint is too worn to be coated over. It's up to you if you wish to follow this advice. Personally, given the amount of work it would be to grind all the paint off, I would clean it thoroughly and paint over it. Even if the new paint doesn't bond well, you can always remove it all later.

Mitchell

[DexterOz]

Yeah not sure as paint area is not small its more than 50 sq m. I will do a clean up with water and detergent and see how it goes then i can plan.

[kel]

@DexterOz  I have used grout to repair cracks in concrete and have found it to extremely good for the job. Last year I had to replace some floor tiles in a commercial kitchen that I work in, after grouting the tiles I had a bit of grout left over so instead of throwing it out , I used it to fill in some rather large cracks in the concrete .  Considering the concrete gets pressure washed every day, the grout has withstood this perfectly. A few months ago I was assisting a mate with his Reno job, and I filled all the cracks in his driveway and paths with grout before we painted it all. Came up a treat. 
cheers kel

[DexterOz]

@kel  thanks, Are you referring to this

[kel]

@DexterOz i used the davco grout,@ around $8 for a 1.5kg bag. the driveway had previously been painted,i filled all the cracks with grout and the gave it 2 coats of berger jet dry  paint .came up a treat.

[Prawns]

I had leftover roof tile pointing that  i used to fill some damaged concrete with around my backyard and just left it exposed, its flexable so seems to withstand temperature changes no issues (3 years and repairs still looks like the day i put it in) its also paintable (https://www.bunnings.com.au/dunlop-10l-tile-pointing-charred-ash_p1142417)  I had used a cement slurry in the past but it always seemed to dissapear over time my mix mustnt of been too good maybe but i imagine painting would have protected it

[DexterOz]

Thanks @Prawns @kel