Garden paving slaps - algae off?

[Bebs]

Further to my request of limescale remover and all your kind answers, I have another question.

Anyone know the best product/procedure to clean up garden paving slaps? They have become almost black and green over the years and need some serious work to get back to the original white/grey colour.
A stiff brush and some kind of liquid I assume or a compressor?

Cheers all

[OllieC]

I clean my slabs with a power washer, a bit messy, but a million times easier than srubbing on your knees with a brush !

[Bebs]

OllieC said:

I clean my slabs with a power washer, a bit messy, but a million times easier than srubbing on your knees with a brush !

Thanks Ollie, but the slaps are seriously bad and I'm not sure plain water pressure is going to do it..

[bga]

Bebs said:

OllieC said:

I clean my slabs with a power washer, a bit messy, but a million times easier than srubbing on your knees with a brush !

Thanks Ollie, but the slaps are seriously bad and I'm not sure plain water pressure is going to do it..

I had similar when I moved in to my new place. I got a Halfords pressure washer and it will clean a slab in a couple of minutes. I was really impressed as it was much more effective than scrubbing the damn slabs.

[pmanson]

Pressure washer will do the job but you will get very wet!

I think Karcher do a specific add on for cleaning patios (a round thing that spins on the end of the lance).

[Penny-lope]

Pressure washer is defo the best thing.....great fun, and so satisfying

I need to get a life!

[Bebs]

Penny-lope said:

Pressure washer is defo the best thing.....great fun, and so satisfying

I need to get a life!

[hornetrider]

Bebs said:

OllieC said:

I clean my slabs with a power washer, a bit messy, but a million times easier than srubbing on your knees with a brush !

Thanks Ollie, but the slaps are seriously bad and I'm not sure plain water pressure is going to do it..

I thought it was a typo in the title but you've used it again. You do know it's slabs, right?

[DAVE-W]

Armillatox http://www.armillatox.com/

Great stuff.

Edited by DAVE-W on Wednesday 3rd March 13:13

[whitechief]

I use a Karcher washer with dirt blaster lance on my patio spring time every year and the difference is astonishing.

[Bebs]

hornetrider said:

Bebs said:

OllieC said:

I clean my slabs with a power washer, a bit messy, but a million times easier than srubbing on your knees with a brush !

Thanks Ollie, but the slaps are seriously bad and I'm not sure plain water pressure is going to do it..

I thought it was a typo in the title but you've used it again. You do know it's slabs, right?

Forgive me horne, I'm 100% foreign

[poo at Paul's]

Patio Magic from homebase. Just spray it on with a gargen sprayer or brush it on, make sure it is not due to rain for a day or so, then just leave it. Incredibly, a coupel of weeks later, the algae and moss are gone.

Really works, although I tend to use if for moss and algae on tarmac not slabs.

[_dobbo_]

Pressure washer for sure - it will also bring up decking a treat.

I used mine to blast the decking, shed and fence, then painted the fence and shed and it all looked brand new!

[fido]

Pressure washer +3 - but be careful to avoid the mortar in between slabs -unless you want to redo them.

[anonymous-user]

Penny-lope said:

Pressure washer is defo the best thing.....great fun, and so satisfying

I need to get a life!

Nope, it is a fact. Immensely satisfying. The only issue is aiming for perfection and removing every last ounce of dirt!!

[Wings]

I use diluted brick acid and a deck scrubber, a scrubbing brush on a handle.

[B17NNS]

A Karcher or similar should clean them up a treat.

Failing that, some Patio and Drive cleaner from B&Q will.

[taz turbo]

wings said:

I use diluted brick acid and a deck scrubber, a scrubbing brush on a handle.

+1

Brick acid, is hydrochloric acid based, hydrochloric acid dissolves organics, and is by far the best way to clean flags, block paving. Just watch out for colour fastness of cheap flags or blocks.

Chris.

[Simon Brooks]

jet spray any day of the week, great fun on a hot day (if ever we get one again !!) best to work in a set pattern (one slab at a time) and work towards a drain, remember to check that the drain does not get blocked by all the rubbish you lift with the washer

good luck and have fun

[Simpo Two]

taz turbo said:

Brick acid, is hydrochloric acid based, hydrochloric acid dissolves organics, and is by far the best way to clean flags, block paving. Just watch out for colour fastness of cheap flags or blocks.

It will dissolve limestone too. Is that the stuff garages use to get burnt-on brake dust off alloy wheels?