How do i remove concrete 'stain' from tarmac?

[Purist]

I recently had my patio paved and the builder did a splendid job but unfortunately has left a bit of a mess behind him.

He mixed the cement on boards on my tarmac drive. When he came to wash off the boards with water, the diluted concrete has ran down my drive and now I have a nice runoff of pale cement - in all honesty it isn't too bad but is more noticable the further away you are.

I was wondering if a power spray would remove this or whether there is some kind of solvent that can remove this mark ? A couple of friends (not builders) have remarked that it will be a nightmare to remove.

(Apologies if this is in the wrong forum by the way, but I could'nt think where else to put the post!)

[Dave_L]

This thread might help! Don't forget to pop back and let us know how you get on, ok?

http://ext.pavingexpert.com/cgi-bin....;t=3339

[Purist]

That's great.

Hydrochloric acid it is then, just hope his tarmac eventually blended in Ok.

Thanks for the thread.

[Puzzles]

Hi Purist

I have replied - see the last posting on my epistle! Hope it helps.

I also brushed in fine soil into the new tarmac that joins the old. This has helped blending.

I did think of getting some of the tarmac renovator to run a half metre by four metre bank to cover the worst bits and cover the joins in the tarmac.

The emulsion type sold by my local BMs is £20 for a tub. They suggest adding grit if you need grip.

That too can wait until the spring.

Regards.

[TarmacLady]

Purist, if the tarmac is fairly new, just wait it out -- the volatile oils within th tarmac will work their way out of the mix and will dilute the HCl salts along with it.

Just mind that what you are getting at the builder's merchant is made with asphalt/bitumen...many of the "driveway coatings" being sold in the UK are nowt more than a latex emulsion -- thus they don't stick to the drive, and don't fix the problem.

Supadrive is one that really is of a similar material to that used in the bitmac mix itself, and so will not only bind, but is somewhat like using Oil of Ulay to renew the surface and extend the life of your drive.

[Dave_L]

If the stain really annoys you we'll come along with our planer and take your drive up and relay it! :p

[Purist]

There are a number of articles on the net that say Coca Cola dissolves concrete - due to the phosphoric acid content.

So I can clean my drive with refreshments!

[Dave_L]

*Note to self - Must stop drinking coke!

[seanandruby]

throw away the pnematic tools that caused my h a v s then?
no more need to scabble etc.

[geoffdance]

Hi Purist,

brick acid is good. Be careful with the pressure washer - tarmac is relatively soft, I always turn the pressure way down.

TarmacLady is right with the sealant. Don't know about Supamix but Liquid Road works a treat.

Geoff

[Purist]

I just thought I would mention this.

About six months ago I did try the brick cleaner from B&Q to remove the concrete that the builder had spilt on the tarmac.

It removed the concrete .... and turned my tarmac green !

Six months on and my tarmac shows no sign of fading back to its natural colour. I guess I will be paying for some of that shiny black sealant.

[Dave_L]

Thanks for coming back to us with your not-so-good success story!

[Purist]

I think the 'green effect' are the salts. When it rains the drive returns to it's normal appearance. It is only when it's dry you notice the green.

It hasn't been too dry recently and I only picked up on it about three months ago. I was hoping it would go but that doesn't appear to be the case.