Decking - What causes this?

[terryhawkins]

I laid a new deck in the summer, and it's been treated with 2 coats of Liberon decking oil.

6 months on, and I have marks like this on the decking:

What causes this? And is there any way to get it off?

 

[big-all]

its mould
was the decking pressure treated ??

 

[terryhawkins]

its mould
was the decking pressure treated ??

Yes, it was pressure treated.

Any way to get it off?

 

[freddiemercurystwin]

First get one of these:

 

[freddiemercurystwin]

then add some of this:

 

[freddiemercurystwin]

then a little bit of this:

 

[freddiemercurystwin]

Get yourself one of these:

 

[freddiemercurystwin]

Then use plenty of this:

 

[freddiemercurystwin]

Or alternatively just use on of these:

 

[terryhawkins]

I've already been out with the pressure washer, that didn't shift it.

If I wait until next year to clean it off, will that make my job harder? Will the bleach affect the oil that's on there?

If I clean it now, I won't be able to get a coat of oil on because of the weather.

 

[imamartian]

bleach is good at killing mould. But i personally think exterior timber will go through a whole range of colours and hues... and that spotted effect is just one of many... i'd say only get involved if the structure of the wood is compromised, i.e. rotting.. apart from that enjoy its changing nature.

Incidentally the worst thing about decking in the winter is how slippy it gets !!!

 

[terryhawkins]

bleach is good at killing mould. But i personally think exterior timber will go through a whole range of colours and hues... and that spotted effect is just one of many... i'd say only get involved if the structure of the wood is compromised, i.e. rotting.. apart from that enjoy its changing nature.

Incidentally the worst thing about decking in the winter is how slippy it gets !!!

I don't mind the spotting as it is, my concern is that the whole deck will go black with mould.

Do you think it will get really bad over the winter? Or am I worrying about nothing?

 

[imamartian]

i'm only going by mine.... it's not the rich golden brown colour i put down, but it's not black....

i reckon the pressure washer is a good idea in the spring, and then give it a decking oil treatment to give it its glow back. If the mould gets bad, do the bleach in a bucket thing....

 

[big-all]

i would just live with it all the decking has a chance of going the same way as the wood gets wet
you either have to do the whole lot or you will end up with a patchwork quilt
as said its part off the wood

 

[terryhawkins]

I'll keep an eye on it over the winter.

Does anyone know if the bleach will effect the oil in anyway? Will I need to re oil after using bleach?