Blackbutt Deck, Oil or Stain

[strangerep]

Hi there, my hubby and I have just built a new deck made of blackbutt

Welcome to the deck slaves club.

I am no longer a member of that club, having sold my house ~2 yrs ago. But I will never again buy a place that has an exterior timber deck.

and we love the colour of the timber and are receiving a lot of mixed messages re oil/stain etc

Presumably you've already looked through the previous posts in this thread (and I hope you've also read lots of other posts in this forum)? Lots of info here (sadly, needs to be repeated over and over again).

Blackbutt (especially) will go dirty and ugly over time, regardless of finish. Actually, all timber species do this as tannin leaches out and mould grows.

We have been recommended Cutek CD50 as well as Sikkens Hlse.

I have used both. The Sikkens product started to degrade (in a visually obvious way) after about 3 months, and by 6 months it looked quite crook. So I used Cutek on my deck over quite a few years. Each coat would last 12 months and still look reasonable.

We are thinking an oil or something clear w no colour but not sure about maintenance.

Don't use clear unless you're happy for UV rays to grey your timber rapidly. The Cutek website talks about this.

It isn't a big deck so ok w oiling every 12- 18 months if need be.

It's not just the oiling. You've also got to clean it thoroughly. See older threads which talk about Napisan treatments, oxalic acid, etc.

For new decks, I'm an advocate of letting it weather for some time, while also hosing it off liberally until no more tannin leaches out. Try this experiment: Pour a small cup of water on the deck somewhere not too obvious. Let it dry, and you'll probably see tanning stains left behind where the water has leached it out of the timber. It's desirable to keep hosing the deck until this behaviour stops, or becomes minimal.

BTW, I hope you used 30mm decking, not the thinner 19mm stuff. When I was selling my house, I got professionals in to sand it back to bare timber. Their big sanders remove a LOT of material -- I doubt this could be done more than twice on 19mm boards without seriously compromising the strength of the deck.

[DomAU]

Sadly, I am also a member of the deck slaves club . Mine is also in a full-sun location with just occasional cover from a retractable awning. 80 square meters of ongoing maintenance; it's a love-hate relationship. Just about to re-oil it again tonight actually.

I use Cutek Extreme on mine, with a few different pigments mixed together to get a colour that we liked. I haven't tried other brands of oil on the blackbutt deck. I use Cabots on the front Merbau deck because that's what we started with - I'm not a huge fan of the colour but it seems to last a long time and is much thicker than the cutek. It's a much thicker oil than the cutek. I also think Merbau is just a lot more durable in terms of colour retention than the Blackbutt.

Oh, your blackbutt deck will darken/turn more amber with UV, before then going grey. So if you add pigments to the oil, realise that it will get darker with age; particularly the first 6-12 months.

Cheers,

Dom

[DomAU]

Couple of small things to add;

Having just re-coated my 80 square meters of blackbutt, it took nearly a full 10lt tin of Cutek Extreme; that's over $300- per re-coat which i do at least every 12 months and was doing every 6 months the first 18 months - hadn't ever thought about it, but that's a lot of ongoing expense.

Also, I had to sand-back my front deck today as it was looking a bit rough. I realised that the Cabbots oil is basically more like paint, with the areas of the deck that still looked like wood-colored/ok first going grey upon sanding off the top layer (showing that the wood was actually grey, and it was just the cabbots oil / colour on top that made it look wood coloured). This is different to the cutek product which does not form any film on top of the deck and instead soaks into the wood. The Cabbots keeps forming a thicker and thicker film on top of the wood which later flakes off / ends up like a coat of paint.

Cheers,

Dom