Pergola Wobble

Sorry but those footings are incorrect.
A footing of that type firstly should be 450x450x450 and more importantly the post anchor should be a 300mm long one and set inside the footing!!.
Post anchors should only be dyna-bolted if going on to a large existing slab etc.
The purpose of a footing is to prevent uplift from the wind. I think you should prop up the pergola and re-pour your (larger) footings with the post anchor in-situ.
That being said you will find it much more stable laterally when you screw your battens on

Well spotted with the bolts - there definately should be two per post through the beam.
Your battens need to be (min.) 70x35 if your using sheet roofing otherwise you can use 45x45 or 42x19 (both available in rougher header) if using shadecloth or no cover at all.
Another thing - what pitch have you set your rafters at? They need to be 5' minimum for corrugated colorbond/Lasrelite. You can use trimdeck/Greca type profile at 1' minimum

My rafters are approx 2' pitch. depending on the type of roofing i will probably double up the batten along the back wall to increase the pitch.

Hi Duke,

Im definitely not putting a roof on until i fix the footings.

I will take your advise and use the same design post anchor but at 300mm length.

I left my footings for 3 weeks until i drilled them, is that a decent amount of time to wait before i insert the posts back in?

Just to confirm, when you say i cannot use corrugated do you mean Roma? Can i use the Greca type profile sheets??

Eddie

[quote="Dukekamaya"]You need to dig the concrete out and increase the hole to 450x450x450. With the 90x300mm post anchor fitted to the bottom of the post and 'dangling' in the hole then fill with concrete.
You can prop up the structure with some F-clamps and 90x45 pine etc
http://i31.photobucket.com/albums/c351/Dukekamaya/100_1268.jpg

No worries thats what the forum is for. The pic is actually my house too
Its only a small roof area so should be okay to use 340x340x450-500 deep. I would actually put your battens on and add your extra bolts before re-pouring the footings. It will keep it much, much more stable whilst they set. Use concrete mix too, not rapid set - its much stronger.

How long are the rafters and how far apart are they?
I'll need to check the min. pitch for Greca in polycarb - Roma is definately 5'.
Corrugated colorbond is 5' also so you wil nedd to go with the Trimdeck type profile which has a min. pitch of 1'

Hey Duke.

Still havent done anything yet regarding the posts. I've been away and the rain isnt helping either.

As soon as the weather clears i will be adding the battons and extra bolts no the top of each post.

As i had prevuiously mentioned i am gonna take your advise and remove the existing concrete and bracket, dig the hols a bit deeper and connect 300mm post stirrups and then pour concrete into that!

I will need to hire something from kennards to break the readimix concrete (345x345x345). Can you please suggest the right tool from the kennards website??

My mate has the equivalent to the "Rotary Hammer - Medium Electric". Is that sufficient enough to break the 2 blocks in a couple of hours?

Finally a decent weekend with hopefully a decent week to follow.

I finally redid the footings. I hope you approve this time..

I added an extra bolt to the top of each post as well and braced them against the beam.

Im thinking of adding another set of bracing, on the corners of the ledger beam and the end rafters to keep the rigid left and right, I have plenty of off cuts from the rafters so ill probably use those and ill mount my speakers on them later on.

Unfortunately i didnt get the battens done, so thats next. The pergola is zero pitch, so im gonna need to do some batten slicing i guess to create a 1 to 2 degree pitch for the trim deck roof.

Incase you were wondering the size of the roof (rafters) is 3240 wide by 3100 long.

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Ok - Heres the deal with the roof.

I spoke with the local roof guy and he suggested the following.

For trimdek profile im gonna put a 100mm batten against the wall, a 50mm half way down and something thin or nothing at the end. (or 90x90 then a 45x90)

Still dont know how im gonna nail a fricken 90x90 to the ledger beam and rafers, i might go 3 of 90x45, 2 on the top end nailed (or screwed) in one at a time then the other one half way down.

To cover the width Ill need 4 sheets to 'almost' cover the 3240mm width (i will be short though) at 3150 long including the overhang into the gutter.

Ill screw in the sheets so that the 4 are centred to allow an even gap on each end (about 90mm i think). The guys can make custom barge caps so that the base of the side section of the barge will run evenly along the side of the rafters instead of along with the slope. Ill get the flashing apron and the gutters at that time as well.

Hopefully now, after the footings are now proper, i redo the bracing properly and put the battens, the wobbling is reduced. I feel much more confident though with the new footings. I used about 4.5 bags for each footing!!

I havent removed the props yet either, ill do that on saturday before i return them to Kennards.