# Forum Home Renovation Pergolas, Gazebos, Strombellas & Rotundas  Post size for roofed pergola

## geeseman

Hi Guys
Building a new pergola with a colourbond roof in the backyard. 4.3m X 4.3m.
Had previously built one using cypress pine posts 185X185, and this one was 4mX5m.
I'm looking to use merbau posts this time.  140 x 140mm Merbau Posts, K/D F/J, Decking, Pergola, Fencing, Screening | Fencing Supplies Melbourne, Timber Fencing Supplies, Mornington Peninsula Timber
Similar to those but from Bunnings most likely.
Roof will be simple colorbond. 
Question is do you think the merbau would be sturdy/strong enough at 4.3mX4.3m single span?
Im thinking they are quite a bit stronger than the cypress I used previously. 
The next size up is 190X190 and Im thinking this may be overkill.
Design is similar to those on this page https://www.aaronsoutdoor.com.au/lif...ment/pergolas/ 
thanks for any help.

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