Cleaning a van roof, my tip and a question

Yesterday I cleaned the roof of our Kemerton XL of all the accumulated mold and debris. It took me several hours, today I'm nursing a slightly swollen knee from going up and down the ladder so many times.

My tip, our Status TV aerial, the white plastic dome from the bathroom extractor fan and some white plastic conduit for our 2nd solar panel came up a treat in just a few minutes after a few sprays of Domestos Mold and Mildew Remover. After an initial wash with Turtle Wax car shampoo these plastics were still mottled with dark spots. Well, I was amazed how little time it took after a spray with the Domestos product, soon they wee looking as new.

This success got me thinking, could an application of patio cleaner achieve the same miraculous results on the black mold without the hours it took me yesterday, even prevent its formation?

A significant constituent of patio cleaner is usually sodium hypochlorite, which in its weaker dilutions is known as bleach. You may also think of it as chlorine. Sodium hypochlorite may attack some forms of plastics and rubber, causing embrittlement, fading etc. It can also cause corrosion in some metals. Do I need to write any more?

I use sodium hypochlorite for cleaning algae etc. from rendered walls, block paving etc. I buy it at much cheaper prices in agricultural merchants rather than buying proprietary patio cleaners and it does a wonderful long lasting job, but I take great care when spraying it near upvc windows. I wouldn’t dream of using it on my van roof. Sorry!

A while back , Wet and Forget was being hailed as the greatest thing since sliced bread for van roofs. Its a patio cleaner like any other and it had caravan roofs in its list of uses but I believe it no longer lists that.

The Bargee wrote:...
I use sodium hypochlorite for cleaning algae etc. from rendered walls, block paving etc. I buy it at much cheaper prices in agricultural merchants rather than buying proprietary patio cleaners and it does a wonderful long lasting job, but I take great care when spraying it near upvc windows. I wouldn’t dream of using it on my van roof. Sorry!
...

You might be talking about Deosan Red Label Hypochlorite which can be bought from Mole Country Stores.  It's extremely powerful and effective on patios and has to be used with great care.  I certainly wouldn't use it on a motorhome.  

In the past I have used a small amount of toilet bleach gel applied to the affected areas on the motorhome with a toothbrush and then rinsed it off 20 minutes later.  That is quite effective as it is in the bathroom.  However, through the Forum I was introduced to Cillit Bang Black Mould Remover which is easier and probably safer to use and does a very good job.

All the cleaning solutions mentioned contain a certain concentration of sodium hypochlorite (aka bleach). Cillit Bang is about 2.2%, Domestos type bleach is usually around 4%, patio cleaner (or the agricultural products) can be 15%. Then it depends how you dilute it. These products are basically diluted bleach, repackaged and branded. HG also make a good mould remover which my wife uses, and I managed to bleach the knees of my jeans white when using that a few weeks ago! Even swimming pool “chlorine” is basically bleach. I use bleach to shock treat our pool, but do use the proprietary chlorine tablets once the pool is put into use just in case anybody complains!

If you are talking about careful attention to small areas then provided these are carefully rinsed I suspect there will be no damage. A van roof is more like a parade ground and I suspect most squaddies would be splashing the bleach around rather than use the toothbrush when the RSM wasn’t looking. I suspect RV was thinking more of splashing the stuff around generally as one would do with a patio, but on a Sevel type PVC roof there are lots of corners for this to lie trapped and potentially damage plastic skylights, rubberised seals, paint etc.

Some algae remover solutions include caravans in the list of applications, e.g.Jarder Concentrate Spray & Leave which specifically says no bleach or acid content. Just need to check the manufacturers specification.
They don't work immediately, need a few days but then last for a while preventing regrowth.

I know it sounds self-righteous but I find cleaning the roof little but often is far better than leaving it until the algae grows and then having to do a major cleaning job with chemicals and polish.  Frequent cleaning needn't take long and gets faster as the technique improves.

I happen to have some patio cleaners and none seem to contain any Domestos type hypochlorite ingredients.

Defenders concentrated path and patio cleaner which I picked up after clearing out a house of a recently deceased relative containes 5% cationic surfactant, 5% Sodium Triphosphate, Sodium Metasilicate and NTA. My guess is that this was bought some time ago by her.

Spear and Jackson "Spray and Leave" contains 5% Benzalkonium Chroride.

Stone Guard Anti Moss that I bought some years ago on QVC, It was made in France. My container doesn't list the ingredients but looking in Amazon it would appear to contain quartenary ammonium surfactant, CAS 68424-85-1 which is Benzalkonium chloride again and alkyl benzyl dimethyl ammonium chroride.

The Stone Guard product suggests it can be used on plastics.
Incidentally from Wiki I read that Benzalkonium Chloride is widely used but can be poisonous if taken in large amounts, deliberate or accidentally.

We previously asked the AS Forum about annual cleaning of algae from the roof of our van, Muc-Off Motorhome and Caravan Cleaner was recommended. We purchased this online from Amazon UK and were delighted with how easy it was to use to clean the roof and no worries about damage to seals or fittings on the roof or the van. Thanks to all who answered our query last time. Twins on 2R

One Chem Spray and Leave from Amazon. No acid, No bleach Non caustic and biodegradable.

Just to stick my two pennorth in, we recently had a new porch and front door installed at home.
The (local, very quick, reasonably priced and reliable) fitter recommended Wonder Wipes (B&Q/ Wickes etc) for cleaning the white upvc.

They also clean the roof area of our van with ease after a (prior wash). Ours has cleaned up a treat !!  Other cleaning wipes are available !!

Sorry if you've already tried it, but a strong solution of Fenwicks Motorhome Cleaner worked wonders on my roof last week.
Rod

Wonder wipes are great but I cleaned some paint of a rubber covered phone case the other day and it took the rubber coating straight off too!

I used both Fenwick's motorhome cleaner and Wonder Wipes yesterday. 
The motorhome cleaner did an excellent job on the 'van and the Wonder Wipes were used to extract baked-on grime, mud and cr*p off the motorhome lead.
I wouldn't have wanted t use them the other way around.