# Forum Home Renovation Pergolas, Gazebos, Strombellas & Rotundas  Best timber for Pergola posts

## Colsy

Hi all, 
I am building a pergola at the back of my place, 9 by 3.6. I have been going to Bunnings to get 90 x 90 permapine posts but they all look warped or they are wet to the touch which makes me think they may warp when dry. 
What is the best timber to use for a truly straight post? 
I saw the Merbau laminated posts, they looked pretty true and straight but are they intended for outdoors? I am at this moment intending to concrete them directly in to the ground. If I was to use stirrups, has anyone got any tips on installing so that they are level height and lined up? 
Cheers people!

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## president_ltd

if you are going into the ground (or concrete) then your ONLY choice would be H4 treated pine.  if on stirrups (i.e. not actually in contact with the ground) then you can get by with H3 instead. 
you can get the above in structural rating too, e.g. F13/F17 etc - but you will need to know what you need to use relative to the load it is supporting. 
treated pine posts are fine if you are painting them. 
if you are after a hardwood look (e.g. something that you oil instead), then my suggestion would be to use Cypress posts.  there is a brand of them called "Cypress Gold" or "Gold Cypress" which are available in 100x100 or 125x125 specifically for that purposes and are nicely dressed already without too many knot holes. 
here is what cypress posts look like along with a 'hardwood' pergola structure over a deck.

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## Colsy

Thanks president. I have seen the Cypress Gold in Bunnings and yeah, I really like that hardwood look. Decision made on posts.

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## president_ltd

in the pics the cypress gold posts are just oiled with a Sikkens product of some description - can't remember which but either SIkkens Cetol HLS or Filter 7 (or both). 
the rest of the pergola roof structure shown in the pics is laminated KD hardwood, probably Tas Oak also oiled with same said sikkens product(s). 
the idea here is that Cypress is far more able to withstand the elements (rain, sun) but DOES require a re-oil (just with a cloth) probably once every 12 months or so. 
if you cannot be bothered doing that then suggest you go with paint over treated pine instead.

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## Colsy

Thanks again president, you must have ESP. I was going to ask two more questions:
1. which oil product did you use?
2. what is the roof timber? 
But you already answered, thanks heaps!

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