Jetwash for patio - how powerful?

[ben_eunos]

I've got a Karcher K2 pressure washer which I understand is max rated at 110bar.

To clean the algae off the patio I have to hold the nozzle no less than about 15cm away from the tiles. This takes about 90 seconds per tile, and means it takes me half a day to do them all.

How much more pressure should I be looking at to speed this up significantly? And what would you recommend?

[OutInTheShed]

Get some chemicals and/or a brush.

A garden sprayer to damp the surface with a bit of detergent, then a soft broom and rinse it away, is often far quicker and quieter than a jetwash.

Mre pressure will often damage the grout or even slabs.

[M1AGM]

Yes as above, use a chemical anti-algae treatment with a watering can and after a couple of weeks it will all be gone, and wont grow back quickly. If you jetwash it with force it will still grow and you risk popping the grout out of the joints.

[butchstewie]

Have you got an actual patio cleaner attachment?

I have a 20 year old Kranzle pressure washer and last year I bought a proper patio cleaning attachment for it.

Winced a bit as I think it was £160 but it took two hours to do the whole drive.

If the Karcher attachment does the same thing it's a cracking piece of kit.

[Radec]

As above, use the dedicated patio attachment.
I use it on my Karcher, makes light work of the patio and doesn't take that long compared to just using the lance by itself.

[Earthdweller]

Yup just get the karcher patio cleaner attachment it's night and day to just using the lance

Very little spray and takes 1/3 of the time

[dhutch]

Its not really the pressure you want to look at, but the flowrate.

[renmure]

5 liter bottle of BAC50 from Amazon, diluted at about 20/1 liberally sprayed over the algae on a dry day and you will be sorted.

[Simpo Two]

As said, get the patio cleaner attachment (round thing with brushstrip edges). It's 10x quicker and annoys the neighbours 10x less.

[ben_eunos]

The patio cleaner attachment in my experience is a chocolate teapot.

The only benefit to using it is to avoid splashback, but otherwise is much slower to use

[ben_eunos]

dhutch said:

Its not really the pressure you want to look at, but the flowrate.

What flowrate should I be looking for then?

[butchstewie]

Nicest way possible the K2 is a cheap cheerful domestic pressure washer.

It'll do what you want but the patio cleaner or dirt blaster will make it easier than trying to use the nozzle you'd use for washing the car.

[Huzzah]

ben_eunos said:

dhutch said:

Its not really the pressure you want to look at, but the flowrate.

What flowrate should I be looking for then?

I have one of these.

https://www.screwfix.com/p/titan-ttb2200prw-150bar...


It's okay, but I regard it as the minimum spec for my use, 100 sqm takes most of the day.

[smifffymoto2]

Alot of the time it’s quicker and easier to get a chap in with the right kit.
21l/min machine and hypo after.

[dhutch]

ben_eunos said:

dhutch said:

Its not really the pressure you want to look at, but the flowrate.

What flowrate should I be looking for then?

More is better, and will get the job done faster what is your budget! How often do you plan to use it?


Kärcher...K4.....1.8kW...420 l/h .......similar to my 25yo Kärcher 411
Nilfisk....E145...2.1kW....500 l/h .....refurbished item link below

https://www.cleanstore.co.uk/products/Product.asp?...


I also agree a patio head is well worth it if that is what you are using it for, in terms of keeping the mess together if nothing else.

The other thing to consider is the hose length and quality, but most are awful and after market ones readily available.

[The Gauge]

ben_eunos said:

The patio cleaner attachment in my experience is a chocolate teapot.

The only benefit to using it is to avoid splashback, but otherwise is much slower to use

I've always assumed this. Reducing splashback aside, I cant see how an attachment can lift more dirt than just holding the lance above it? If the high pressure water coming from the lance can't shift the dirt then surely a spinning attachment with 2 or 4 nozzles is only going to reduce that direct blasting power?

[reggie747]

Get some sodium hypochlorite and read the instructions.

[butchstewie]

The Gauge said:

I've always assumed this. Reducing splashback aside, I cant see how an attachment can lift more dirt than just holding the lance above it? If the high pressure water coming from the lance can't shift the dirt then surely a spinning attachment with 2 or 4 nozzles is only going to reduce that direct blasting power?

I thought that.

Tried to clean the patio and drive with the Kranzle dirt blaster and gave up and reluctantly paid for the patio cleaner.

It's a fking beast.

I assume there's a difference between cheaper and more higher end washers but trust me a good pressure washer with a patio cleaner attachment will absolutely clean the patio or driveway.

[Simpo Two]

The Gauge said:

ben_eunos said:

The patio cleaner attachment in my experience is a chocolate teapot.

The only benefit to using it is to avoid splashback, but otherwise is much slower to use

I've always assumed this. Reducing splashback aside, I cant see how an attachment can lift more dirt than just holding the lance above it? If the high pressure water coming from the lance can't shift the dirt then surely a spinning attachment with 2 or 4 nozzles is only going to reduce that direct blasting power?

My Nilfisk machine came with a patio cleaner and it's far more efficient than using the lance directly. I'm not sure why, it just is.

[Alorotom]

reggie747 said:

Get some sodium hypochlorite and read the instructions.

This.

I ordered 2x 5l bottles from Amazon last year

Diluted as per the instructions, hosed the area to dampen and then used a soft broom to brush it on.

Did about 150sqm in about 2hrs - then rinsed and over a day or so it all came up as-new. I was really surprised how effective it was - especially after taking days jet washing it earlier in the year!

(I only used one bottle of it)