Lichen, what lichen!! - Sandstone Patio cleaning

[RAPressureWashing]

Couple of before and after photos of a Sandstone patio we did this week, home-owner wasn't sure if we could clean it better then him and there's "no-way" you remove the lichen (black spots) he says.

Before-1
[IMG]http://img.photobucket.com/albums....MG]

After-1
[IMG]http://img.photobucket.com/albums....MG]

Before-2
[IMG]http://img.photobucket.com/albums....MG]

After-2
[IMG]http://img.photobucket.com/albums....MG]

Nuff said

[local patios and driveway]

credit where its due, that second set of pics really shows the difference

[Bob_A]

Yes the second of pics really does show how well it has come up.
Without giving away too many trade scecrets can you say what chemicals you used?

[rab1]

hot wash with steam?

[RAPressureWashing]

Sorry everyone photos should have just opened? maybe things have changed loading photos via photo bucket?
And the thread title shouldn't have looked like that either?
If a mod wants to change anything please do so.

rab1
No steam or heat just a chemical wash with cold water.

[higgness]

StoneTec Sandstone cleaner?

[RAPressureWashing]

StoneTec Sandstone cleaner?

No not Stonetec

I can out the answer up, but anyone else want to have a guess?

[seanandruby]

BLEACH.

[lutonlagerlout]

roger you need to go into your album settings on photobucket and switch off link back to album
it completely threw me the other night as well

i guess you are talking "roger's jollop"?
LLL :;):

[RAPressureWashing]

BLEACH.

Sean
Sodium Hypochlorite please,
Same as the "Roger's Jollop" but no soap and mixed at 2:1 with a dwell time of 30mins plus, there was also a load of tree sap which had turned the paving black in a couple places but the mix took care of it.

[r896neo]

I have a customer with some riven sandstone thats been down 10 years and its under an acer and trellis with climbers so endless stuff dropped on it.

I tried qualgex which really helped but Hypochlorite was the only thing to really get the lichen and weird stains from the acer off but it came up like new. I even tried a dash of baby shampoo so thanks for that tip!

Worth all the effort trying to dam it. Using the blower to direct washings afterwards was a big help.

Have you ever had an problems around plants or lawns roger?

Cracking job by the way.

[Al Jardin]

Roger
Does sodium hypochlorite work on block paving? One of our customers has a block paved drive with the usual dark algae & some lichens. If so do you apply with a watering can or sprayer then brush in? I'm assuming the run off can go down a road drain?

Cheers.
Al

[RAPressureWashing]

I have a customer with some riven sandstone thats been down 10 years and its under an acer and trellis with climbers so endless stuff dropped on it.

I tried qualgex which really helped but Hypochlorite was the only thing to really get the lichen and weird stains from the acer off but it came up like new. I even tried a dash of baby shampoo so thanks for that tip!

Worth all the effort trying to dam it. Using the blower to direct washings afterwards was a big help.

Have you ever had an problems around plants or lawns roger?

Cracking job by the way.

You need to be careful around plants and lawns, what we do is water plants and grass first, cover any low lying and tender plants with polythene so to protect them from spray, once past the said plants, and no more chance of them being sprayed remove polythene and re water the plants esp. on hot days.

[RAPressureWashing]

Roger
Does sodium hypochlorite work on block paving? One of our customers has a block paved drive with the usual dark algae & some lichens. If so do you apply with a watering can or sprayer then brush in? I'm assuming the run off can go down a road drain?

Cheers.
Al

Yes it does work on block paving, I use a pump-up sprayer to apply, dwell for around 20 mins, the run off down drains is an issue, I've never had a problem but understand there can be issues.

[Al Jardin]

Thanks Roger
I'll hunt for some locally.

Al