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Can you put polyurethane on a Merbau deck?

khwajas
Growing in Experience

Can you put polyurethane on a Merbau deck?

We have an under cover merbau deck.  I used Cabot’s aqua deck to cover it.  As it is not very shiny and requires more maintenance I was wondering if I could put a coat of polyurethane on top of it to make it look better and blow dust off.  Is there any issue doing this? 

EricL
Bunnings Team Member
Bunnings Team Member

Re: Deck Maintenance

Hello @khwajas 

 

Thanks for sharing your question about your deck. Can you please tell us if you sanded the surface of the deck, or did you just paint straight over the existing cover of the deck? I don't recommend putting polyurethane on a deck surface as it is prone to chipping. 

 

If you are looking for a smooth deck surface, I suggest sanding the surface of your deck and finishing it off with a high grit sandpaper and sanding between coats. 

 

If you have any other questions we can help with, please let us know.

 

Eric

 

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MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: Can you put polyurethane on a Merbau deck?

Hi @khwajas,

 

I thought I'd jump into the discussion and ask if you could post some images of your deck so our helpful members can provide advice. Let me know if you need a hand uploading those pictures.

 

Polyurethanes are not used on decks for a number of reasons. As @EricL has pointed out they scratch, chip and wear in an outdoor environment. Once they've done so, you'll need to re-sand the whole deck to restore it. Also, your deck will become extremely slippery in wet weather and will be a hazard. Polyurethanes look great, but in a high-wear situation like a deck, they are, in fact, more maintenance than oil, and when they do need maintenance, it's a huge process.

 

Please be aware that whenever you see a glossy deck, it's more than likely an oiled deck that has had water sprayed over it for some glamour shots, not a deck that is glossy all the time.

 

Mitchell

 

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khwajas
Growing in Experience

Re: Can you put polyurethane on a Merbau deck?

Many thanks. I gave finished putting aqua deck coats.  It looks good.  And I am not going to use polyurethane as it is oil based and plus your recommendation.  

what I am annoyed by us the filler I used which was supposed to be me eBay but left visible marks. It was intergeain beand.  

IMG_4907.jpeg

IMG_4905.jpeg

Can’t cover it.  Attached sone photos. 

MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: Can you put polyurethane on a Merbau deck?

I'm sorry to hear that the filler did not match your board colouring well, @khwajas. Was it the Intergrain 180g Jarrah / Merbau Woodblend Putty? Apart from sanding the filler back and recoating the deck, there's not much I could suggest to resolve that issue.

 

Mitchell

 

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khwajas
Growing in Experience

Re: Can you put polyurethane on a Merbau deck?

MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: Can you put polyurethane on a Merbau deck?

What sort of damage were you filling, @khwajas? It doesn't relate to the colour difference, but there appears to be a fair bit of filler left on the surface of the boards. Were all the holes that large, or would sanding the area flat and removing the filler from the top of the board where it would not be needed reduce the amount of filler in those areas? 

 

The problem with fillers is that there's only one colour for Merbau, whereas timber from different suppliers, or even from the same tree, can consist of various colours. My Merbau deck has different boards ranging from a red hue to a darker brown. Any one filler would not match well with all the boards.

 

Mitchell

 

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khwajas
Growing in Experience

Re: Can you put polyurethane on a Merbau deck?

Thx.  The deck builder was a useless guy he installed some of the timber which had large holes. I tried to sand down.   

MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: Can you put polyurethane on a Merbau deck?

I'm sorry to hear that @khwajas

 

Is this a new deck, and did you add the filler?

 

Mitchell

 

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