new merbau deck, laminated merbau-does it need to be weathered?

i have just built a new deck in merbau i am a little confused on whether i have to weather it before sealing, hearing too many different opinions. we used spa & deck on an old deck which came up great, what i am wanting to know is do i have to weather this deck before applying spa & deck or will it be alright to just clean with what i have heard oxalic acid or napisan or spa & deck have a product called powerlift. By cleaning it with 1 of these products can it be sealed straight away? once it has been coated with spa & deck will the tannins still come from the timber?

I also have the same decking timber in which i am wanting to put up as a screen in an undercover area i am worried about it staining the wall under it not sure what to do am i best to seal it then put it up?

Another thing i would like to ask is i have laminated timber to build posts & a hand rail for outdoor stairs ie timber posts & rail with stainless cable, does laminated timber still leech tannins? The reason i ask is that i am also using it for internal stairs as well i just dont want it to stain everything so im just not sure if i coat it/seal it straight away

any information will be greatly appreciated thanks:)

Regarding letting it weather, good luck getting a straight answer on that one. Probably best to follow the directions on the tin of whatever finish you use. I let mine weather (it said to on the tin) and it came up OK.

Regarding leaching of tannin, it will only do that if it gets wet. The staining will only occur on areas that the water runs off to. If it's undercover and doesn't get wet, it wont leach.

Hi Jods,

I did a fence in merbau over cement render. I coated the timber first with cabot's aquadeck and then assembled it. I got caught with the leaching problem when it rained 2 days later, where I drilled the holes to screw the merbau to the fence as I was putting it up. I couldn't clean the stain from the render. :C Hind sight says that I should have let it weather in the rain first or predrilled the holes and painted them with the aquadeck before they went up.

Cheers

Bryan

Hi Tung Tied

What did you do about the leaching onto the render? I have the same problem, my render sugggested a Dulux product which has a stain in it that can be applied to cover over the leaching as well as provide protection against future leaching.

Hi bluprint,

Sorry about the late response, I've been away. The best remedy for the merbau is to let it weather, preferably before it's used, but you learn something new every day. I've let it just sit there now for around 6 months to let the rain do its job.

I've bought some paint to cover the render again when the leaching is over. I tried nearly everything at the time from metho, turps, floor cleaner, car cleaner, pressure hose to clean the render but nothing would move it. The staining has faded and I'll get to it when the weather warms up.

Cheers

Bryan

Hi Bryan

Thanks for your response. I was interested to know how you dealt with it, because I've got the same problem. I had a brand new merbau fence put in about 4 months ago and the first rain made it leach all over my brand new rendered wall. Not happy!
I did a bit of research and found this link:

http://www.renovateforum.com/showthread.php?t=75429

It says to use Napisan to clean the Merbau, as this has the same active ingredients as DeckClean products.

Well, I gave it a try on my new deck and it worked a treat, so then I tried my new fence. And, not only did it clean the wood really well, it also (surprisingly) took the leaching stains off my newly rendered wall. I think it'll probably need another clean at the end of the winter months and then I'll oil the wood, but so far, I'm very happy with it.

Perhaps it may be worth a try for your wall too? Seeing as you've tried everything else it might just work?!

Good luck with it all, I'd be interested to know how you go.

Cheers
Bluprint

Blueprint, is you wall an acrylic render or cement?

And how did you apply the napisan to the render?


Tools

Hi Tools

To be honest I don't know if it's acrylic or cement....
I applied the Napisan as per the instructions at:

http://www.renovateforum.com/showthread.php?t=75429

Basically it's a third of a container of Napisan to half a bucket of warm water. Dissolve the Napisan, take a good strong brush and scrub. It'll take quite a few buckets of water and a couple of kilos of Napisan depending on how big your area is.

I'd suggest you try it on an inconspicous spot on the rendered wall first to make sure that the colour doesn't lift, but it didn't on my wall.

Cheers
Bluprint