Concrete Drive Way Turning Black

[tartempion]

I had the drive way and more concreted (to avoid perimeter wall to slip away).

I was told the concrete would turn ugly black within one year and I think it begins to do so (rain etc?)

Is there a solution to this and what would the cost be per sqm?

I thought there might be some special oil absorbing paint, but could that be used outside?

I saw some nice finishing of drive ways in some star pattern and heard the cost would be 350B sqm, and I wonder if that resist the monsoon here.

[Bangyai]

Never heard of concrete turning black before ??? Do you mean it is black from oil leaks from your car or something else. You might try mixing up a large bucket with some washing powder with just a little bleach then throw that over it once a day. If its in a shaded area it might be caused by a sort of black mould so the bleach should kill this off.

[tartempion]

I was warned this would happen by an other farang here in Isaan. Therefore that man used small stones (gravier in French)

I first had concrete poured outside along the perimeter wall to avoid the wall slipping off and some concrete in a corner.

Must have been 1 year ago, that's the one getting black, exposed to sun mostly.

Then I had the drive way concreted 6 months ago and I suspect it will have the same fate.

It's really a big area also to throw bucketssss with washing powder and bleach

I am looking for some permanent solution, coating or something similar.

Strange this would only happen to me

[MMR]

There are concrete sealers available at hardware stores.

Would still require a good scrub every now and again.

[Rimmer]

I had the drive way and more concreted (to avoid perimeter wall to slip away).

I was told the concrete would turn ugly black within one year and I think it begins to do so (rain etc?)

Is there a solution to this and what would the cost be per sqm?

I thought there might be some special oil absorbing paint, but could that be used outside?

I saw some nice finishing of drive ways in some star pattern and heard the cost would be 350B sqm, and I wonder if that resist the monsoon here.

Have you tried jet washing the 'black' off? It may just be be algea.

Anti algea add mixture is available to mix with cement when it is put down to stop this problem.

The star pattern you are talking about is probably stamped concrete, very nice finish using a rubber stamp on concrete then putting on a color hardener and sealing it. For 350 baht a meter you can also sand wash or put down tiles over the concrete.

BUT IF you put anything using cement on top of the old drive make sure you use a bonding agent or else the new cement will crack and lift.

[jojothai]

hiconcrete itself does not turn black. it is not the concrete unless possibly the water includes the algae forming agent. if so the contractor should have known to use tap water and not from the local canal / pond.as previous comment it must be a local algae. so you will need to seal the surface and then it is easier to clean.if you already have some black then get it cleaned first, then put the surface sealer.Ask what the locals do for it.if it repeats then the locals will most probably know what causes the problem and how to treat it.jojo

[Crossy]

The active ingredient in these stay clean concretes is Titanium dioxide (the same stuff used to make white paint white) added to the mix before laying.

http://concretedecor.net/All_Access/504/CD504_New_Tech.cfm

[Beardog]

I am not sure if they carry muriatic acid here in Thailand. I used to have to clean 33 greyhound bus stalls with it when I was a kid working for my dad. It will strip any matter down to the original finish cement will be gray again. if you do find some be careful using it as it is very caustic + the smell will or can give you a headache. Apply with a cement raking broom come back 1 hr later hose off. Very easy to use. It will also stip the gunk & grime from vehicles that leak like washing mud off of cement. If you do find some wash any areas on your body that get backsplash immediately & do not get it in your eyes. Same if you do flush it out with copious amounts of drinking water & or boric acid (eye wash)

Edited September 19, 2008 by Beardog

[jaideeguy]

Yes, they do sell muriatic acid here....[go to a swimming pool shop or chemical supply] i get it for swimming pool water balancing by the 5 gal pail and yes it is dangerous/and unpleasant to work with...get a good resperator and set up some fans to blow away the fumes.

but it sounds like the Op's problem is fungus/mold and can be killed with househole bleach, again...be careful if you can get it in industrial strength. If it is mold, then it will leave a residue behind that can be cleaned with a power cleaner.

And a cheap good finish is a paint that they sell locally in limited colors and I think it's called 'tennis court and roofing paint' ....it's water based and dries to a hard and semi smoth finish that last long.

[Beardog]

Yes, they do sell muriatic acid here....[go to a swimming pool shop or chemical supply] i get it for swimming pool water balancing by the 5 gal pail and yes it is dangerous/and unpleasant to work with...get a good resperator and set up some fans to blow away the fumes.

but it sounds like the Op's problem is fungus/mold and can be killed with househole bleach, again...be careful if you can get it in industrial strength. If it is mold, then it will leave a residue behind that can be cleaned with a power cleaner.

And a cheap good finish is a paint that they sell locally in limited colors and I think it's called 'tennis court and roofing paint' ....it's water based and dries to a hard and semi smoth finish that last long.

thanks for the news it is available. i am sure at some point I will be in need of some & do appreciate you saving me a lot of legwork on where to find it. Cheers To You!!!!

[sometime]

I had the drive way and more concreted (to avoid perimeter wall to slip away).

I was told the concrete would turn ugly black within one year and I think it begins to do so (rain etc?)

Is there a solution to this and what would the cost be per sqm?

I thought there might be some special oil absorbing paint, but could that be used outside?

I saw some nice finishing of drive ways in some star pattern and heard the cost would be 350B sqm, and I wonder if that resist the monsoon here.

My path to the rear of the house is also black due to the constant rain; it rarely dries out due to the concrete being very very porous, a totally crap mix ,builders skimping on cement.

I first used pool acid (hydrochloric) this leaves you with a sloppy mess to hose off, and you need gloves goggles and wellingtons.

Then I reverted to pool chlorine 10% liquid, this costs around 360 baht for 25lt, the dilution I used was 5lt water to 1lt chlorine in a garden watering can, then watered the liquid all over the path, at this dilution no risk to the skin.

Then you can sit back and watch all the black just fade away, with the occasional scrub using a deck brush on the obstinate parts, and you don’t have to hose off as it soon dies off.

This I will have to continue to do until I take drastic measures and replace the path.

[Milo]

Pressure washer only good for the first year or two, takes the 'fat' off the surface leaving it more open, more difficult to clean each year. Global House etc sell roofing paint that's pretty cheap, reasonably hard-wearing, done three different driveways with this now and no wear complaints. Drying time bit of a nightmare though, can't park on it for a week without it sticking to your tyres. Before anybody points out shouldn't have bought roofing paint for a driveway, you know how it is here, ask for the correct coating, give you what they've got with a shrug of the shoulders and 'same same'!

Goes on really well with one of those airless sprayers too, which driveway paint wouldn't with all the grit in it, and not too slippery when wet either. Certainly better than all these houses you see with a tiled drive, asking for bones broken!

[tartempion]

Thanks, think that roofing paint idea is good for the driveway. Driveway still looks good though.

It's the outside perimeter wall concrete that's turning black, concrete from different company and older that driveway, think it's fungus and will try "sometimes" idea of to water with pool chlorine 10%.

[mdechgan]

If the concrete surface is not smooth it will get dirty. Dirt, oil, algae. Concrete itself never turns black, it turns whiter over the years.

Especially the "sai lahng" or the concrete with the small stones/gravel mixed. Concrete walls are also like that.

Just have to physically brush the surface and clean it often.

Sometimes just use a sealer to seal the surface. Its kinda like a urethane that keeps the surface clean and a shiney gloss. Home Pro sells them. Can't remember the name though but I know the bucket when I se it.

[rubik101]

http://www.radonseal.com/color-sealer/color-sealer.htm

This type of product will cure your problem. You will need to prepare the surface properly with a good cleaning, pressure wash should do it. Allow to dry and then apply this stuff.

You can get a great finish with just two coats. You can make it any colour you like, within reason. I would go for the earth tones or the reds. I've seen it in blues and green and it looked good.

It is water based and dries with a near gloss finish. If your concrete is rough or you want a smoother finish, skim the surface with a thin layer of new concrete and then apply a few days later. You can pattern the new skim any way you like or leave it plain.

I've seen a resort in the North where all the floors, inside and out, were done in this manner and they looked really cool!

[rubik101]

btw, you can use this in ponds, fish tanks, water tanks etc.

These people have it here in Thailand

http://thaibondall.com/naturalseal_eng.php

[JRinger]

http://www.radonseal.com/color-sealer/color-sealer.htm

This type of product will cure your problem. You will need to prepare the surface properly with a good cleaning, pressure wash should do it. Allow to dry and then apply this stuff.

You can get a great finish with just two coats. You can make it any colour you like, within reason. I would go for the earth tones or the reds. I've seen it in blues and green and it looked good.

It is water based and dries with a near gloss finish. If your concrete is rough or you want a smoother finish, skim the surface with a thin layer of new concrete and then apply a few days later. You can pattern the new skim any way you like or leave it plain.

I've seen a resort in the North where all the floors, inside and out, were done in this manner and they looked really cool!

Is this product available here? according to their website:

MADE IN USA

Products not sold through retail stores. Available exclusively from:

Radon Mitigation & Concrete Waterproofing Co.

Novion Inc., 18 L'Hermitage Drive, Shelton, CT 06484 USA