Advice and Recommendations for Cleaning Roughcast

[petej42]

Hello

My house has roughcast finished walls which are starting to get a stain which looks red/orange when rubbed with a damp cloth. I gather that this is algae.

I understand that this type of finish should be soft washed rather than pressure washed and preferably not with a bleach based product.

The walls are quite high and I would prefer not to be working off ladders, so I need something that will project the water/cleaner mix perhaps 6 to 8 meters.

This is where I come a bit unstuck, I need a washer with enough power to spray the cleaning solution this far yet not so powerful that it strips the roughcast off from the walls. Is it just a case of aiming at the walls but not standing too close, or am I missing something?

Has anyone any experience of this type of cleaning and can anyone recommend a suitable pressure washer and cleaning solution to remove the algae

I have an old nilfisk pressure washer, but I need something that allows the detergent to be mixed with the water when spraying which this doesn’t do and I dont know whether its too high pressure either.

Any help greatly appreciated

Pete

 

[Tigercubrider]

One suggestion is one of those telescopic poles with a brush fitted, intended for ordinary garden hosesdoes your nilfisk need to be connected to mains water? My cheap b&q plus karacher can be connected to a water butt

So a plastic dustbin filled with a mix of water and bleach then sent up the pole might work?
Also, I had a cheap water butt pump that connected to a garden hose- cost me £25

 

[petej42]

The telescopic pole certainly is an option, just found a 17 ft one on amazon but dont think it will be long enought to reach the top of the gable end. The nilfisk is very good, but wont work directly from a water butt so I would need to get a pump. While I was looking for the telescopic pole, I did come across a lance from nilfisk for about £85 that talks about a reach of about 15 meters which would seem ideal, unfortunately, it doesnt fit my version of Nilfisk - typical, may have to invest in a new pressure washer !!.