What pergola beam length?

[Libbie]

Hi all, 

Ive recently bought a property which has a 1200 mm deep north facing pergola which is a simple pergola with a deciduous grape vine. 

Due to the heat and to use the top of the garden bed as entertaining area I am extending this out / north by 4000 mm - all the way across the front and over the drive. 

I Will leave the existing posts and relocate / repurpose some of the roof Timbers that allow the climber to create a canopy

Thid  be a simple structure nearly for the purpose of holding deciduous ornamental / non fruiting grape vine. 

 Beans - so you can see in the pics I have positioned fence posts where I want these new posts

The horizontal beam for the garage door ( I think it’s laminated timber) is 8 metres long / sits abutt the brick wall. 

My questions 

1. Beam length - I’d like 10 m beams - less posts than existing how long can the beams for the pergola be ie post to post noting this will be positioned vertically on its edge on top of the posts and won’t really be load bearing

i am wanting to 

2. Beam material - suggestions - LVL  laminated ???? these will be painted in Palm beach black, like the rest of the pergola ( WIP) 

Ive since found this link to laminated beam lengths / down however it’s a bit too technical for me

https://wesbeam.com/Wesbeam/media/Documents/Design%20Info%20Docs/WESB0674_e-beam-Brochure-AUG24.pdf

  

 

[MitchellMc]

Hi @Libbie,

It comes down to how many posts you're will to have over this 10m span. According to that span table, there are not beams capable of the 10m without support. So, say you have one post at the 5m mark, you could then use a 240 x 63mm beam.

The more posts you have, the smaller the calibre of beam you can use.

To span a larger distance, you'd typically need to go with an LVL, or you could use solid timber, but you'd probably need two posts over the 10m.

Please let me know if you have any questions.

Mitchell

[Libbie]

Hi Mitchell, 

thsnkyou for helping me out. 
Early this morning I phoned Wesbeam tech support over east & they are excellent for answering power builder & general enquiry, a big shout out to Terry 🙏⭐️✅

as follows; 

Gluepin (?) or another hardwood could do that distance - would beed to investigate further. 

If using Lvl

For 7.8 m span

Must nail or screw together 2-

2 ply 400 x 45 wide - 2 pieces 

Or I can achieve 7200mm span with no lamination - LVL 400 x 63 wide

[Libbie]

Hi Mitchell

I decided on posts 6.5 apart so that’s 3 each side of the house entry. 
Was at my local Bunnings this morning & looked at H3 for the beams over LVL. Would you recommend standard brackets for the fixings? 
again this isn’t load bearing, it’s for a deciduous ornamental grape vine.
cross members (?) will be H3 smaller doc like the existing structure. 

[MitchellMc]

Hi @Libbie,

Were you referring to brackets that fix the beams to the posts? If so, you'd typically notch the top of the post so at least half of the thickness of the beam will sit on it like a shelf and then bolt them together.

Mitchell

[Libbie]

Hi Mitchell

Yes correct brackets hat fit to the beam, 

ok notch & bolt, that is similar to existing, thank you