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My cousin is wanting to erect a 4.1 X 5.0m free standing pergola. It will be single span with only four posts in each corner.
What kind of 100x100 posts would you advise to be exposed to the weather elements?
How do I read the span tables for this to determine the size of beams. Im assuming 240x45 or there abouts would be rough size.
Can i simply notch out the tops of the 100x100 for the bearers and use bolts M10s for these and also use stirrups on the bottoms concreted into ground?
If the length of the pergola is 5m what space could i get away with for additional joists etc and can these simply be joist holders installed.
If there is overhang needed for a visual impact are you better to install the joists above the bearer and notch out or have separate pieces each side with joist holders?
And if installing a sheeted roof does it need to have 15 degrees minimum pitch for water runoff and there fore gutters installed?
Hello @funky-millar
Before you begin, I suggest checking your local council's rules and regulations regarding the size of your pergola. I suspect that there are height and size restrictions that must be followed. Because of the size you'll be building at, I propose engaging the services of a draftsperson to draw up a basic plan for you. They'll be able to integrate all of your requests into the plan including the pitch of the roof and the overhang you're looking for. Plus, it will be safe, built to code and will pass inspection.
In regards to reading span tables, I suggest looking at this discussion - How do you read span tables? by @dowd_hardware. It gives a very good example of how to read span tables.
Here is a link for ideas and inspiration: Top 10 most popular pergola projects
I also suggest having a look at this guide - How to build a pergola
If you need further assistance, please let us know.
Eric
So if i was to build this. Reading from the span tables etc for a 1.2m wide span I can get away with 5.6m @ 240x65 and 4.9m @ 200x65. If I slightly reduce this for cosmetic purposes and exact spacings to 1m then the 5.6m etc will still apply.
Hello @funky-millar
My apologies for the late reply. Please allow us to double check if your proposal is viable. As soon as we have more information, we'll get back to you.
Thank you for your patience.
Eric
Hi @funky-millar,
Could you please try uploading your image again? I am unable to read the span table you're referencing.
Mitchell
The span table is from Hyne.
Hi @funky-millar,
According to the span table, that appears to be correct. However, it's always best to confirm your plan with an engineer or builder. Remember that if you do need to submit plans to the council for a permit, they'll need to be drawn up by a professional.
Mitchell
What is the best way to connect a corner post to a beam on both sides?
If i notch out the post on top to allow for the beams to sit on so the load goes down the post, im fine with this.
But where do the bolts go in to secure it? If one side goes into the posts then the other beam wont have any room also to have the bolts. I will stagger them but no matter which way you do it the bolts will clash.
Hi @funky-millar,
You should be able to offset the bolts so they don't run into each other. I've included a render I created to illustrate.
Mitchell
My sister wants to erect the pergola flat.
Is the best method to build the pergola with the rafters etc set on joist holders so it is flush with the cross beam? Then she wants it to protrude 1m further out. Do you just do this with joist holders also? Effectively the only thing holding up the protruded part will be the joist holders?
I was going to angle it slightly so I could notch the rafters into the cross beam but she doesnt want that look
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