Weapons grade patio cleaner - slate

[Davie_GLA]

I have a lot of slabbed area in the garden and it’s slate, fairly porous.

I neglected it last yet and regret that now.

I’ve tried everything I have, including sodium hypochlorite. Meaty stuff but even that isn’t touching the sides, and I’m using it neat.

I think I need to leave it longer or try something else.

Where can I buy the absolute best, brutalist cleaner? Jet washing helps but takes ages. And needs multiple passes to avoid visible crossover between sweeps.

[JoshSm]

You can absolutely destroy slate if you put the wrong thing on it, so be careful.

Too late now but what you should do with slate is a) start with a decent quality slate and b) seal it, maybe even before laying it.

Try a biocide on it (like BAC50), then wait, assuming it's growth not dirt.

[Davie_GLA]

JoshSm said:

You can absolutely destroy slate if you put the wrong thing on it, so be careful.

Too late now but what you should do with slate is a) start with a decent quality slate and b) seal it, maybe even before laying it.

Try a biocide on it (like BAC50), then wait, assuming it's growth not dirt.

Thanks. It’s a blend off all sorts. Some growth and general dirt and there are patches where the dogs have peed. The urine seems to lift quite easy though but it’s the stubborn grime.

I plan on sealing it this time after cleaning which is part of the reason of wanting to do it right.

[richhead]

Ive always found a stiff brush, washing up liquid and lots of elbow grease to be the best cleaner, i do mine this time every year and thats it.

[Simpo Two]

Davie_GLA said:

Jet washing helps but takes ages. And needs multiple passes to avoid visible crossover between sweeps.

Have you tried a patio cleaner attachment?

[OutInTheShed]

Try bio washing powder or liquid.

[David A]

A rotary floor polisher with a brush attachment. Like the things you see being used on school corridors and hospitals etc put down lists of soapy water and use a brush if uneven or a pad if flat porcelain. Super fast and very very effective.

Forgot to add about £200 used on eBay.

[richhead]

i use a hand held scrubbing brush, less likely to cause damage than a jet wash
and a bucket of soapy water, my patio is about 10x4m and it takes me about 3 hours, looks good as new after, its hard work tho.
https://www.amazon.co.uk/Scrubbing-Brush-Limescale...

something like this

[Davie_GLA]

richhead said:

i use a hand held scrubbing brush, less likely to cause damage than a jet wash
and a bucket of soapy water, my patio is about 10x4m and it takes me about 3 hours, looks good as new after, its hard work tho.
https://www.amazon.co.uk/Scrubbing-Brush-Limescale...

something like this

Commendable but mine is at least twice that size and on 2 levels with stairs. I do have a fairly robust scrubber though but it’s chemicals I’m hoping to find that at least helps things along.

[David A]

Chemicals like hypochlorite will bleach and kill stuff. Bac 50 will kill it. You need something physical to get it off and then you need to rinse it so it doesn’t just sit back down.

We’ve nearly a couple of hundred sq m of porcelain and the hospital style rotary is the best thing and quietest and really fast to do.

One of these and buy a brush
https://ebay.us/m/nQRzFn

[Davie_GLA]

Thanks for that. I might see if I can hire one to see how it goes. Having a look the area is around 120m2 plus some stairs so not massive.

What about sealant? Any recommendations?

[richhead]

Davie_GLA said:

richhead said:

i use a hand held scrubbing brush, less likely to cause damage than a jet wash
and a bucket of soapy water, my patio is about 10x4m and it takes me about 3 hours, looks good as new after, its hard work tho.
https://www.amazon.co.uk/Scrubbing-Brush-Limescale...

something like this

Commendable but mine is at least twice that size and on 2 levels with stairs. I do have a fairly robust scrubber though but it s chemicals I m hoping to find that at least helps things along.

I get what you are saying, but i always wonder what chemicals do to the stone, thats why i use just scrubbing, doesnt sound like a huge area, do you have kids you can use lol
As for sealents, the same aplies, how will they change the stone.
i chose not to seal mine as i prefere the natural look, and haent seen a sealent that doesnt change that.

[smifffymoto2]

Pureseal in Crewe will have chemical suitable for slate.They only do exterior cleaning chemicals.