What is the best size wood for decking?

[titusudawatta]

What is the best size wood for decking 90*19 or 140*90 ?

[EricL · Accepted solution]

Hello @titusudawatta

Welcome to the Bunnings Workshop community. It's wonderful to have you join us, and thank you for sharing your question about which decking panel size is best.

That is a fantastic question and I believe a lot of our members who have built their own deck will have their own take on which one is the best to use. Aside from the obvious differences in size and price, I think using the larger panels gives your deck a bigger look as you don't see as many gaps.

Using the larger panels also means that you won't be using as many screws when attaching your deck panels to your decking frame. The number one benefit I think is that you won't be using as many panels on your deck when using the bigger size. Panel gap also plays a big part in your deck panel layout strategy. 

Here is a link for ideas and inspiration: Inspiring low-level deck builds

Let me call on our experienced members @Adam_W, @Neo19, @Backyardtradie and @diy_hausdesigns for their recommendations.

Please keep us updated with your progress, we look forward to seeing your deck ready for use.

Eric

[Adam_W]

Hi @titusudawatta ,
In some respects it's a personal preference for how it looks. Personally, I prefer the look of wider boards.

At first glance wider boards will seem more expensive but, as @EricL pointed out, you end up using fewer boards & screws and they are faster to install as there are less boards. A 1m wide section uses approximately 11 x 90mm boards whereas you'd use approx 7 x 140mm boards.

[Neo19]

@titusudawatta I agree with Adam in terms of the board size being a matter of personal preference.

I went with the 90x19 for both decks that I have done. Although I liked the look of 140 mm boards, i felt both my decks were not big enough to pull it off! 

I have read wider boards have comparatively higher chance of cupping which needs to be taken in to consideration while planning/installing. Experienced members might know more about this. 

Are you planning to build a deck?

[titusudawatta]

Yes

[EricL]

Hi @titusudawatta

It's good to know that you are proceeding with your decking project. Any photo updates you can provide while you build your deck would be much appreciated. 

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

Eric

[Brad]

If you are doing an ultra low deck the 90mm will give better airflow and wider gaps will help as well, my decking jig does 6mm or 8mm gaps and I personaly prefer 6mm for the less likely to have something drop through the gap.

Cupping will look worse on a wider board and I wouldn't use a cupped board in a new build, at best you will put strain on the fixings trying to flatten it out. A well maintained deck with proper fixings spaced at recomended intervals should resist cupping.