Pressure Washing

A high pressure water jet can (and will) cut rubber, lift graphics and remove paint so must always be used with great care.  Only use it on areas where the finish is sound and original and never closer than 15cm to the surface.

In my experience I have found that the most effective way to remove green algae is with a good quality microfibre cloth and a bucket of water without detergent/soap etc.  You need to keep rinsing the cloth and you will have to change the water a few times but you only have to attend to any area once and its safe to work around vents, aerials etc.

If any marks remain after that then I would spot clean with a damp loth and Fenwicks motorhome cleaner.

Hope this helps.

Peter

It is the Motorhome cleaner I use. Quote from their web site:

Fenwicks Motorhome Cleaner - Safe for use on all motorhome surfaces

Fenwicks Motorhome Cleaner Concentrate easily removes streaks, green algae, road traffic film, diesel fumes, and over wintering grime, etc. It is suitable for cleaning plastics, aluminium, acrylic windows, GRP, ABS, fibreglass, decals, sealants and much more. Highly concentrated formula, guaranteed results.

Available in 1 Litre bottle

How to use Fenwicks Motorhome Cleaner

Step 1: Pour 2 capfuls of Fenwicks Motorhome Cleaner Concentrate into 5 litres of warm or cold clean water.
Step 2: Apply to surfaces from bottom to top using a spray, sponge or brush.
Step 3: Allow 30 secs to 1 mins to soak in, but do not allow to dry.
Step 4: Agitate with a sponge or soft brush.
Step 5: Rinse thoroughly with water from top to bottom, or for that showroom finish just add Fenwicks Bobby Dazzler to the rinse water.

Handy hints

1) A 1 to 10 solution will remove stubborn marks and black streaks.
2) Rinsing with Fenwicks Bobby Dazzler protects and makes cleaning easier.
3) If using a pressure washer, use a dilution rate of 200-1 at the lance end.

End quote.

I've had no problems with it.

Peter