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Removing mould on 987.2 / 2009 roof?


PCGB Member
I've tried lots of potions on this growing fungus growth on my roof, all to no avail, inc Autoglym.
The lives outside and has done for 6 years in my ownership. During winter a top cover is fitted.

We have big trees around the house, so not ideal i suppose.

Anyone with good solutions or is it best to go to a pro detailing shop?


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Vacuum to lift the whats there, Milton sterilising tablets - very diluted, supposed to kill the spores, your choice of cleaner to get rid of the residue.

Would suggest this may be made worse by a cover - especially if it's non breathable.....

Looks like tree pollen to me in _DCS0082.JPG, although pics may deceive

I'm not even sure the 1st pic is fungus.

Milton do a sterilising fluid too which is good. Just dilute it with water and apply.

When I had my 987 Boxster I always used 303 Convertible Roof/Fabric Cleaner and then the 303 Convertible roof protector
Great products.
As been said try Miltons to kill the the mould .
Thoroughly clean the roof with a fabric cleaner many to choose from use a soft brush to agiitate may take a couple of goes, I have used a powerwasher on extremely bad green roofs yes I know it's not advised but done carefully not much choice with a roof that bad.
Once as clean as possible it will need a reproof tried a few over the years my go to is Fabsil Gold .
Do it at least once a year or even twice.
As a detailer it can be hard time consuming work but if not left to get to green or dirty is best practice.
Have soaked a small area with Miltons, 1/4 tablet in 1.25 L of cold water. Soaked an old towl in the solution too and laid to rest on the soaked area for an hour. Rinsed down, agitated the spots with a old tooth brush, but still there as before.

Local detail shops charge about £150 to clean and seal.
When this hot sun has passed will try again, thanks for the advice as ever Cliff.
Try some autoglym int shampoo after works as well anything might have to agitate a bit more vigorously on stubborn marks .
Not really rocket science just a bit of graft and time you can save yourself some money doing it yourself.
Yeah do it out of the sun .
I would go with a brush on Fabsil Gold save masking up time spray goes everywhere even the slightest breeze .
A careful brush section a time works, if you do get a drip have a cloth ready to remove from paint or windows .
All the best.
I have the 303 protector and Fabsil Gold

I apply both by either sponge or brush.
Decanted out into a Chinese takeaway container :)

@911hillclimber I would have though the tooth brush would have agitated the marks out, maybe try a Meguiars Triple Detail Brush, but gently, stiffer bristles
Bought some magic detergent powder off eBay..
cool day, no full sunshine, so followed the instructions!
wet, soak the hot solution, brush with nylon brush.
wait 20 mins.
washed like mad with hose water.

Dry it all off and examine those marks…
Still there, but slightly diminished.

Foam was very green in the soiled places, so something positive.
Think I’ll do it again.
Overall, the top looks much blacker, so I presume cleaner, but far from done.
Step in the right direction remember once happy it's as clean as possible and once dry give it a hoover with a soft brush pick up any fluff bits of dust before reproof.
Yes indeed, first job to to get these green spots off, they may be 'ded' by now.

Will use the Autoglym potions I have to clean after the spots are gone and to seal the whole top.

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