Not DIY woman needs help, re stains on patio slabs- please!

[phoenixwoman]

Dear All
Hope I have posted this in the right place? If not please forgive me- a bit new at the concept of DIY...
Please help if you can- have searched the internet but can't seem to find the answer.
Basically, I had beige patio slabs laid last year in a new patio. This summer I noticed a strange rusty orange stain on a few of the concrete slabs in the centre. I have not left anything rusty/metal out. Can't think what it might be.
I have tried power washing it with a Karcher and bleach- twice- and it didn't touch the stains
Does anyone have idea what caused the stains and more importantly, how to get of them? Ideally by myself (speaking as a woman who struggles with working out a Havelock hose pipe)
Many thanks for your help

Phoenix

 

[JohnD]

I suspect it is coming from ironstone in the aggregate of the concrete. There is a very slim chance they were made from contaminated ballast which included scrap iron fragments.

If any metal was cut up, ground off or welded nearby, particles may have flown through the air and landed on your paving. Even a tiny particle will do this. So will nails, screws etc dropped on the slab

I doubt you can do anything about it. There are acids that remove rust stains, but acids attack concrete too.

If you are lucky it will stop happening after a while and perhaps you can rub it off the surface with a lump of mortar or something (which will abrade the surface). Don't use brick which will stain it red.

If you can post a photo the staining pattern may give us some ideas
//www.diynot.com/forums/viewtopic.php?t=129539

 

[WabbitPoo]

Were the slabs natual stone or concrete imitiations?

 

[phoenixwoman]

Many thanks for both replies, guys

The slabs were concrete-ish- definiately not stone.
Staining pattern looks like something orange/rusty has pooled on one sqaure slab and run in little rivers onto 6 of the other slabs and into the indentions. The rest of the patio is untouched. It does look like something external and on the surface has caused it rather than something in the concrete

I can't post a photo (yet) as I haven't learnt how to upload (I know I am a sad case! Not very practical. Have decided my talents are in other areas, excluding using Havelock hosepipes)

I'll have a go at uploading a photo this weekend

I can't think of what might have caused it- the other slabs the only thing I can think of was that I left a petrol lawn on the patio for about two months, covered up. No petrol leaked and the majority of the casing was plastic/pvc, and it was about six feet away from the staining

No metal nearby that I am aware of, or nails etc in the slabs, but then what do I know?

It looks awful- like my own version of the Texas Chain Saw Massacre in the middle of the patio. I was hoping to sell up the house as well.

It is driving me nuts. (Especially as next week I have to tackle the idiot's guide to filling in my brick path where the little bits of concrete (pointing?) have disappeared between the bricks and that looks a bit daunting and that's another whole new experience. They are going to love me at B&Q....)

Will try and post a photo for some futher advice- thanks so much taking the time to reply
Phoenix

 

[joe-90]

If you go to Wickes and go to the cement bags and additives you will see some concrete cleaner for £5.69 for 5 litres. (Not patio cleaner).

If that doesn't get it off then nothing will. It's good stuff.

 

[phoenixwoman]

Thanks for that Joe90- will try it this weekend

Fingers crossed....

 

[^woody^]

I would not use concrete cleaner.

This will be acid based and will remove a bit of the cement from the surface of the slab and open some pors which will lead to more stain and dirtier slabs - requiring more frequent cleaning.

If the cause of the stain is iron in the mix then you wont get it out and have to wait for it to erode naturally.

A photo would be good.

Have you tried a strong fairy liquid solution and a stiff brush?

 

[ian18]

I too have got orange stains but this came from using evergreen grass fertilizer on the grass and some landed on the slabs. when it rained it left orange dots and stains.

Anybody know haw I can get rid of it.

tried patio cleaner and bleach to no avail

 

[phoenixwoman]

Thanks guys for that.
I have used lawn feed in the past bit but this is not drops and drizzles- it looks like someting has pooled on one slab and collected and then run into little rivers on to half a dozen other slabs. Orange/rust coulered as I said.

I don't want to spoile or ruin the slabs buy using the wrong stuff

I know how to use a digital camera but will have a go for the first time at up loading a picture this weekend for any suggestions

many thanks again

Phoenix