Merbau Leaching over Painted Render

[Wid]

I have a merbau deck which is surrounded by freshly painted rendered walls. I am planning the build a small fence with matching merbau on top of the painted render but I am worried that the merbau will leach and permently stain the paint. The paint is a light cream\bone colour.
I know the merbau tanins stain concrete but I am not sure about painted surfaces. Does anyone have experiance with this and if so is there any easy ways to avoid it.

[sol381]

depends on how long the deck ha s been down. If youve had a storm or wet the deck then it may be ok. It does stain wood but can be cleaned a lot easier than concrete.
Normally when a merbau deck goes down its a good idea to wait for rain or soak it thoroughly with a hose to remove all the tannins.
Usually only bleeds once or twice so you might be ok.

[silentC]

He's talking about building a small fence on top of the painted render, which would be new timber, not the existing deck.

It most definitely will stain it. Not sure how permanent a stain it will be but as it's a light coloured paint, I wouldn't take the chance. You can get products designed to leach the tannin out of merbau and similar timbers. Try your local hardware. You'd want to make up your fence and then either apply some of this stuff, or leave it outside to weather before putting it near the paint.

It can take weeks or months for all the tannin to leach out. I've got a deck out the back that I finished about 6 weeks ago and even with all the rain we've had lately, it's still leaching out.

[Wid]

Thanks silentc,
I have some room in the back yard so I will weather them for a little while first. I was hoping to get it done for Xmas but never mind

[David L]

When my new merbau decking was laid I was advised to hose it off several times
to give it a good wash that certainly made a difference.
If you are allowed to hose it sure speedes up the process of getting rid of tannins.