# Forum Home Renovation Decking  Joining posts to stirrups?

## Headbelt

When joing posts to stirrups do you sit the post's weight down on the stirrup and the bolts are there to stop sideways movement or do you keep the post bottoms of the stirrup and the bolts hold the load?

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## ringtail

Give clearance at the bottom of the post. Depending on what type of stirrup you have you can vary the clearance. On the high wind type I use a piece of decking board, on the other types, use a 2 pieces of fibro. Dont forget to seal the bottom of the post before you mount it up. Probably just as easy to use 2 opposing wedges, get the clearance you want, clamp and drill first hole, install 1 bolt then remove the wedges, drill 2nd hole.

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## cherub65

Post must bear on the base of bracket to comply with load specifications

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## Headbelt

ok,thanks but now im confused, who is right???

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## cherub65

Note 1 page 6 http://www.pryda.com.au/uploads/Prod...uly%202010.pdf

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## ringtail

Believe what you want, I'm over it

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## ringtail

These are the only type of stirrups that should be used for decks that are not built on top of a existing slab and this is how they should be set up. No ifs, no buts, end of story

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## Keg

> These are the only type of stirrups that should be used for decks that are not built on top of a existing slab

  Hmm, sorry to hijack, but does that mean that as almost all of ours are above an existing slab that they are actually ok.?

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## ringtail

Firstly, sorry for snapping it earlier - having a bad day. Keg, by existing slab I'm referring to building a low deck over a concrete patio slab where you would have to chemset studs into the slab and use a different kind of stirrup. As discussed a while ago, yours will do the job but are not ideal, dont stress it. I really dont understand why there are so many choices of concrete in stirrups when all are inferior ( some massively so ) to the high wind type stirrup

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## Keg

Can't believe you threw a little tantrum, te he. Guess not everyone has heard that you wrote the book.

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## ringtail

Woke up and just had the sh$ts this morning. Dunno, maybe cause I'm 40 today. Anyway, went fishing, caught a feed - all good.

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## Keg

Oh, Happy Birthday!! I reckon maybe it was because you were up all night last night re-writing the book.

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## ringtail

Cheers Keg. Could be, those books dont write themselves. Could also be the fact that I'm officially now a crusty old bastard  :Tongue: . Good thing I only look 20, the perfect disguise, rock out with the nieces and nephews and get all grumpy old man when its suits me  :Biggrin:

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## cherub65

Ringtail, Had a job recently knocked back by an engineer for not having posts correctly installed in striups. Couldn't pack out had to replace. Can tell you we were not impressed.

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## ringtail

I'd say your engineer needs to go back to uni. With the high wind stirrup, the crossbar is not a load bearing member. It is only there to hold the two sides of the stirrup together, not to take the weight of the structure. The 2 x M12 bolts should take all the load and transfer it to the stirrup via clamping action not weight bearing on the cross bar. I would have engaged a different engineer. You could have just packed it fibro as it is not compressible and a perfectly legal packing material and the engineer can jamb it up his you know where.

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## cherub65

Cross bar is designed to take load, check with pryda

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## ringtail

I dont use pryda stuff, not because it isnt any good but my builders yard doesnt stock it. Even if the cross bar is designed to take load, why dont they make the whole stirrup out of 90 mm flat bar instead of 50 mm. I did have a look at the pryda site and all those figures that they give are for uplift only. Having the post sit down hard on the cross bar has zero effect on uplift. The bar also has no bearing on the live or dead load of the structure and it does say that the load will more than likely be limited by the post, not the stirrup. Each M12 gal bolt will shear at around 12 tonne. There are 2 per post. You could support almost the entire weight of the average timber house on 2 x M12 bolts alone. I also noted that the uplift force of those high wind jobs is massive compared to the girly stirrups they also make. It also says that those high wind stirrups should not be used to support a post that has balustrading attatched to it - what bollocks. Heaps of builders put the stirrups too low when placing them into the concrete and end up wedging the post up to get the 75 mm clearance for termites. You would have to be the first person I have ever heard of getting knocked back by an engineer. I guess its the first time for you and can only assume that before this engineer incident you also left the post higher than the cross bar ?

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## intertd6

> These are the only type of stirrups that should be used for decks that are not built on top of a existing slab and this is how they should be set up. No ifs, no buts, end of story

  There are many types of stirrup designs which are all adequate to do the job, as longs as they are strong enough for the loads applied to them thats all that really matters. The bolts will tear out of the endgrain long before they reach their shear failure point. Keeping the post off the bottom is just good trade practice to prevent rotting of less durable timbers.
regards inter

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## cherub65

Ringtail, 
Irrespective of how many times i have done things in the past if the manufacturer and or a engineer tell me to install a product a different way it would be foolish and irresponsible of me not to listen. Maybe my engineer was being picky, but that's what he's paid for. Anyone that works on our sites works to or above standard, I wouldn't expect less from him. 
I would also expect that most people on this site (due to the big green shed) would be using Pryda brackets or equivalent and should follow there installation instructions.

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## ringtail

I hear what you are saying cherub but, for the engineer to throw good building practice out the window and ignore common sense is not been picky IMO, its been very conservative. A engineer is meant to look outside the square and make his/ her own conclusions about what is safe / sound / right/ wrong etc... simply by applying what he/she has learnt at uni. Just because pryda state that the post must rest on the crossbar to achieve the stated results in their brochure doesnt make it gospel. As I said before, the crossbar has zero effect on uplift and these are the only figures that pryda state. Did the engineer give reason for having to drop the posts down ? if not why not ? I never take anything they say as gospel until they can qualify their judgement with logic. If he simply says - because it says so on the pryda website - then thats just ridiculous. Of course there are certain things that are set in stone in the building industry but this is not one of them. Engineering is all about coming up with acceptable solutions to a given problem. If something cant be done one way then the engineer must come up with another way. Engineers should question their peers judgements and draw their own conclusions with confidence as a qualified professional. Of cousre the posts can be placed on the crossbar, but should they be? I lift them up to give the post added protection from rot and ant attack and allow inspection of the base of the post - to me this is logical and only increases the performance and lifespan of the post without comprimising the strucural integrity of the deck. I would like to meet a engineer that can disagree with me based on logic and enginnering principles, rather than the " because I say so " method. A lot of engineers will put all sorts of rubbish out there but at the end of the day its not their time or money that is wasted just so they dont have to use their brain. Question everything.

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## Stan 101

> I hear what you are saying cherub but, for the engineer to throw good building practice out the window and ignore common sense is not been picky IMO, its been very conservative.

  What I get from the above quote is that a qualified engineer is to disregard the manufacturer's spec, their engineering testing department, the independant auditing and think, 'bugger it I'll just do what the carpenter wants. I don't want to be seen as conservative.'  
The reason many certifying engineers don't override what a manufacturer's in house and testing engineers specify is that they are not fully aware of all all codes and manufacturing specifics. A very smart move by the certifying engineer. 
If however the builder / carpenter wishes to use the product in a manner that is not completely in line with the spec, a quick call to the reputable manufacturer's engineering department could offer up an alternative certification for a one off nominal fee up to a mutually agreed set of load cases. Used to do this often.  
The trick is to inform the certifying engineer in advance, often by faxing or email the cert with cover letter before inspection. Certifying engineer then has time to call the manufacturer's engineering department and seek clarification and authenticity and no time is lost.  
Ringtail, I'm curious to know the brand of the high capacity uplift post supports you use.   
Regards,

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## ringtail

Thats not what I'm suggesting at all Stan. What I'm saying is that a professional engineer should be not be so hasty to hind behind the skirt of a manufacturer. If the engineer knocked the post because it was not sitting on the cross bar and demanded it be rectified ( at great cost I'm assuming) I would sure as hell demand he prove it to be structurally inadequate. Like Ive said before, the cross bar provides no up lift benefit and 2 x M12 bolts are easily able to cope with any load imposed on that post - so prove it or get stuffed. Thats all I'm saying - know your subject and be prepared to walk the walk if someone questions you. Anyway, I'm going to continue to set my posts up as I and everybody else I know does and whether people choose to keep them down or lift them up is their own choice. As long as there is 75 mm clearance to the ground it matters not. 
I use GBC brand stirrups and brackets, but only because thats what my builders yard stocks. Judging by the phone number they are on the sunny coast.

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## stevoh741

I'm with you ringtail. I've been building decks for years and you are spot on. I wouldn't do my footings any other way. That brochure probably came from bumrings which would explain the dodgy drawings!

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## Stan 101

> ok,thanks but now im confused, who is right???

  Now common sense states the manufacturer and design engineers who wrote the specification unless there is another *suitably qualified* person who can offer you calcs to back up their statements.

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## Stan 101

> Thats not what I'm suggesting at all Stan.

  No? Why state the following?   

> What I'm saying is that a professional engineer should be not be so hasty to hind behind the skirt of a manufacturer.

  Yes how incompetant of the qualified engineer to blatently disregard the tech sheet of the one of the most qualified timber engineers in the country. I bet the silly goose follows all the building codes.   

> If the engineer knocked the post because it was not sitting on the cross  bar and demanded it be rectified ( at great cost I'm assuming) I would  sure as hell demand he prove it to be structurally inadequate.

  You are in no position to demand anything. You installed outside the scope of 'fit for purpose' for that product. At your expense you could call the engineering department of the manufacturer and request a letter of compliance for your situation if they passed. If not you rectify.    

> Like Ive said before, the cross bar provides no up lift benefit and 2 x M12 bolts are easily able to cope with any load imposed on that post - so prove it or get stuffed.

  Again the onus is on you to prove it or stay stuffed. Have you ever even considered the reason for the post being supported on the cross member is required for the extra edge distance of the lower bolt? Forces are with the grain, but I'm sure you calculated that before you told senior engineers to get stuffed because you know better. 
And besides, I thought you said this in a previous post:   

> Having the post sit down hard on the cross bar has zero effect on uplift.

  Have you ever even considered the reason for the post being supported on  the cross member is required for the extra edge distance of the lower  bolt?  Having forces with the grain, holding the post up from the cross member can eventually force split / delamination under dead load.  As I said, forces are with the grain, but I'm sure you calculated that before  you told senior engineers to get stuffed because you know better.   

> Each M12 gal bolt will shear at around 12 tonne. There are 2 per post.  You could support almost the entire weight of the average timber house  on 2 x M12 bolts alone.

  The governing factor is the bolt with the grain, not the bolt. That's why you will see as the joint group capacity of the post gets higher, the post support capacity goes up.   

> I also noted that the uplift force of those high wind jobs is massive compared to the girly stirrups they also make.

  The 'girly' post supports you refer to are 'fit for purpose'. That's a first year term. We saw the same mentaility again recently after the Yasi home inspections. Builders demanding green hardwood roof trusses because 'that pine sh*t' is no good.
Pity they had no idea that pine trusses perform just as well as hardwood and couldn't be convinced but data collection and testing do not lie.  
A few knew better and refused to follow installation guides as well. Like the guy who refused to run binders on the bottom chord of their ceiling less shed roof. He blamed the building code for his trusses sheering through the nail plate at the truss heels. He's been putting up trusses for 20 years. He thought engineers should go back to uni, just like you. 
Pity the guy couldn't be bothered following the code and the install guidelines and simply install row rows of 70x35 f5 binder on the truss bottom chords. 
You just can't tell some people. 
Cheers,

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## r3nov8or

Seems to me that Pryda is simply ensuring a simple way for their high wind stirrups to be installed ensuring that there is a 'certain engineering minimum' of solid timber below the bottom bolt for uplift resistance. I'd say that anyone that raises a post in this Pryda stirrup is non-compliant to that inherent design feature.

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## ringtail

Hmmm, I guess I touched a nerve eh stan. You wouldnt be an engineer by chance would you ? Lets get one thing perfectly clear. I follow my engineers instructions to the absolute letter. For you to suggest that I dont is both arrogant and presumptuous. I have never been instructed by a engineer to sit posts on the cross bar or knocked by a certifier for having clearance. We are talking about post stirrups ONLY here and whether leaving a gap under the post is good building practice, which it is. I would rather sacrifice 19 mm timber section on the bottom bolt in order to preserve the integrity of the post rather than have the bottom of the post rendered useless through rot and ant infestation. I'm sure you are not niave enough to think there is no difference between theory and reality ? Yes, in theory the uplift may be comprimised by having the lower bolt closer to the end of the post, in reality however it will never pull through as the top bolt would have to either sheer completely at both the bolt head and nut simultaneously or pull through aswell, which we all know wont happen. I think you are also forgetting the massive amount of clamping force the opposing flat bar sections have on the post. Tell me stan, who has more uplift resistance, the people on this forum and all around the country that are building verandahs using the " girly " but fit for purpose (thats a first year term you know) stirrups or me using a high wind stirrup with clearance under the post ? Because thats what it comes down to. If the uplift is still far superior to other stirrups that could be legally used then what is the problem ? 
As far as spltting post - again, theory vs reality stan. Have you ever seen it happen ? no, me either. I have seen plenty of rotten post bottoms that have ants nesting in them though. 
 The fact that they are engineers does not make them god. I have, on every occasion, substituted M12 bolts for the M10's that engineers spec as I believe the M10's are inferior but the engineer says they will do the job. Does that make me wreckless and wrong too ? I do, despite what you may think, have the utmost respect for engineers. I put the my life and lives of my clients in their hands. I also repsect my doctor but question his every move. Why not ask questions stan ? worst case scenario is you might learn something - but engineers know everything right ?

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## Stan 101

> Hmmm, I guess I touched a nerve eh stan.

  Yes you did. By offering advise on this forum that goes directly against the specifications of the engineering spec of the manufacturer.   

> I follow my engineers instructions to the absolute letter. For you to suggest that I dont is both arrogant and presumptuous.

  Arrogant and presumptous? Following are your quote.  

> I have, on every occasion, substituted M12 bolts for the M10's that  engineers spec as I believe the M10's are inferior but the engineer says  they will do the job.

   and this one   

> If the engineer knocked the post because it was not sitting on the cross  bar and demanded it be rectified ( at great cost I'm assuming) I would  sure as hell demand he prove it to be structurally inadequate.

  And this doozy.   

> These are the only type of stirrups that should be used for decks that  are not built on top of a existing slab and this is how they should be  set up. _No ifs, no buts, end of story_

  So should your statement should have been "*I follow my engineers instructions to the absolute letter.* but only when I want" because you are showing blatent disregard to the Pryda engineer's specification. 
So what is it Ringtail? You follow the the engineer to the letter or you make it up as you go along? You have contradicted yourself enough on this by now, surely?     

> I have never been instructed by a engineer to sit posts on the cross bar or knocked by a certifier for having clearance.

  You claim to not use the Pryda post supports in question. It's a mute point.    

> in reality however it will never pull through as the top bolt would have to either sheer completely at both the bolt head and nut simultaneously or pull through aswell, which we all know wont happen.

  Thank god we can now close down the Cyclone Centre at JCU because Ringtail thinks it's unnessessary. What would those fools at the Cyclone Testing Centre know, anyway?      

> Tell me stan, who has more uplift resistance, the people on this forum and all around the country that are building verandahs using the " girly " but fit for purpose (thats a first year term you know) stirrups or me using a high wind stirrup with clearance under the post ? Because thats what it comes down to. If the uplift is still far superior to other stirrups that could be legally used then what is the problem ?

  The probloem Ringtail is not in the bracket at all. It's your blatent disregard for building codes and the engineers who designed and specified the post support in question and then passing it on as fact on this forum for DIY people to read. 
Now twice I have noted that based on the spec of your job, you could have the post to post support connection checked, by the certifying engineer, with the post not bearing on the cross member. This is the correct method.   

> As far as spltting post - again, theory vs reality stan. Have you ever seen it happen ? no, me either.

  Well actually, yes I have. You should get out more.

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## ringtail

Geez you draw a long bow stan. 
What is wrong with substituting M12 for M10 - enlighten me. Is it wrong to substitute gal decking nails with SS for better corrosion resistance ? Same argument. Do you run the exact tyre pressures that the manufacturer of your car recommends ? if you dont then you are blatently disregarding the engineers recommendations, even though you will get better tyre life and fuel consumption running different tyre pressures - give me a break. 
I do follow my engineers instructions to the letter - when there are instructions to follow. If the designer had noted on the plans that the posts must sit on the crossbar, then thats where they would go. As there has never been the detail on any plans, I set the post as I always have. If the plans had to pass through the engineer first and he / she noted the post on bar, then thats what would happen. Again, it has never been required. Does the big green shed hand out pryda how to manuals with every pryda stirrup sold - I dont think so. I guess thats why the OP raised the question in the first place. I have merley passed on my experience in setting up posts, based on how I do it as drummed into me doing my time. So it seems I cant win. It is widely regarded as good building practice yet is frowned upon ( apparently) by engineers. I suspect that your attack on me is based on the fact that I have suggested that I dont believe engineers advice and everybody else should do the same - you are quite wrong. I believe it, but if it can be improved by something as simple as upsizing bolts( for example) then I am guilty. When a lot of engineers detail says something like - *4 x M10 gal bolts min,* how is upgrading to 4 x M12  disregarding the engineers advice. I have read and understood the advice, but choose to use M12 bolts instead. Its my call. If I used M8 bolts then that would be a issue. I suppose tightening the bolts without a certified torque wrench is also disregarding the bolt manufacturers engineering department ? 
The no iffs, no butts end of storey comment, was wrong and I apologised for it. In non cyclonic areas there are a variety of stirrups that will do the job - none however, aswell as the high wind and that was the only point I was trying make at the time. 
" I'm with you ringtail. I've been building decks for years and you are  spot on. I wouldn't do my footings any other way. That brochure probably  came from bumrings which would explain the dodgy drawings! "
Better have a crack at Stevoh741 too eh. :Tongue:  
Please tell me exactly what building codes I am violating and I mean exactly -page number and clause in the BCA  
Perhaps the certifier does not require a engineer to sign off on the stirrups prior to approval because their is no issue - I dont know, I'm not the certifier but Ive never had a request for a engineers inspection of stirrups from one. Pryda should technically provide a form 15 with every stirrup sold. 
And finally  WARNING Information supplied within posts is not to be considered as detailed formal instructions to complete a task.  * Members following such information do so at their own risk.*

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## chrisp

I don't want to get caught in the crossfire between Stan 101 and ringtail - both who I respect as forum contributors. 
But there has been several mentions of 'engineer' so I thought I'd throw my 2 cents in.  :Smilie:  
I'm not a civil or mechanic engineer, but I have done a bit of stress and stain calculations in my time.  I'd be concerned on a few fronts:   Firstly, Pryda state: "The design loads tabulated above require that: (a) the timber post must bear on the Post Anchor base and (b) all posts must be a minimum of 90x90 mm section."  There is no 'it might be a good idea to...', etc.  They state '*it must bear*'. I appreciate the end grain rot considerations, but to sit the post up off the base means all the force is on the bolts.  Say 2 (bolts) x 90mm x 12mm.  The bearing surface is 2190 mm2.  If the post sits on the plate, the bearing surface is 90mm x 90mm = 8100 mm2.  The on the bearing part of the timber (force / area) is ~4 times greater if the post is suspended by the bolts. There will be some extra coupling between the post and anchor due to the 'clamping' action of the bolts, however, I wouldn't depend upon it over the life of the installation.  i.e. timber shrinks and the clamping force is lost.Won't the bolt holes 'rot' too?
As an engineer, I'd be very reluctant to ignore manufacturer's explicit instructions. 
Stepping back a little, I'd be more concerned about the choice of timber for the posts for its stress rating and rot resistance.   :Smilie:

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## ringtail

Agree chrisp, but those load ratings are for uplift only, not live or dead load. Therefore, by moving the post up you are only altering the uplift capacity slightly - how much, who knows, but the ratring would still be significantly higher than that required in non cyclonic areas. In your figures are you calculating the crossbar as 90 x 50 mm or 90 x 90 ?

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## chrisp

> In your figures are you calculating the crossbar as 90 x 50 mm or 90 x 90 ?

  I was assuming a 90 x 90 post/crossbar with 2 x 12mm bolts.  Hence the 2 (bolts) x 90mm (length of bolt in the timber)  x 12 mm (diameter of the bolt) = (the vertical cross sectional area of two bolts on the end grain). 
I do note that some of them have access holes in the plate which will reduce the cross sectional area too. 
Anyway, my post was really meant to be a little bit of an insight to how an engineer might look at the problem.  I appreciate that there is also a 'real world' (where we engineers don't live  :Smilie:  ) where other considerations such as long term rot come in to play.   :Smilie:

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## Stan 101

[QUOTE=ringtail;843086]  

> Geez you draw a long bow stan.

  I'm not the one recommending to disregard manufacturer's spec.   

> What is wrong with substituting M12 for M10 - enlighten me.

  Where edge distance comes into play.             

> Is it wrong to substitute gal decking nails with SS for better corrosion resistance ? Same argument.

  I have no idea what you are referring in the above quote..      

> Do you run the exact tyre pressures that the manufacturer of your car recommends ?

  and therein lies the issue you seem to be avoiding in your replies. Tyre pressures are a 'recommendation' The Pryda Post Support spec is not a recommendation. It is an installation spec that is to be adhered to to the letter. That's the part you can't seem to come to terms with.     

> If the plans had to pass through the engineer first and he / she noted the post on bar, then thats what would happen. Again, it has never been required.

  Because the guidelines for installation have been either misinterperated, or missed all together by your certifier / engineer does not make it right and is no rational point of recourse for you. Ignorance or disregard now the facts have been pointed out to you is no excuse.     

> When a lot of engineers detail says something like - *4 x M10 gal bolts min,* how is upgrading to 4 x M12  disregarding the engineers advice. I have read and understood the advice, but choose to use M12 bolts instead. Its my call.

  I've already told you; edge distance. You're a carpenter. That should be in the forefront of your mind.      

> Better have a crack at Stevoh741 too eh.

  He's not digging himself into a hole trying to prove an incorrect point for others in the forum to read. He's just simply misinformed regarding his whole statement. 
And Ringtail, I'm not having a crack at you. I'm having a 'crack' at your misguided views you are stating in this thread.   

> Please tell me exactly what building codes I am violating and I mean exactly -page number and clause in the BCA

  No, the onus on you is to prove Pryda wrong. Their product is already independently certified.   

> Pryda should technically provide a form 15 with every stirrup sold.

  So isn't that an issue of your certifier being a little flaky on his form 15 requirement if he is passing the project without one. I'm sure Pryda would be happy to offer form 15s. They do whenever requested, however the onus is not on them to supply the form 15 without request.  
Anyway, I've spoken enough on this. Any rational person reading this thread will now, hopefully not be sidetracked into disregarding installation guidelines. 
Cheers,

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## stevoh741

[QUOTE=Stan 101;843156][QUOTE=ringtail;843086]
Where edge distance comes into play.  
The high wind anchors that we use come with a m12 hole. Of course if the hole only allowed an m10 then you would use an m10.          
I have no idea what you are referring in the above quote.. 
changing gal for ss (stainless steel) - not a hard one for those in the building game...            
I've already told you; edge distance. You're a carpenter. That should be in the forefront of your mind. 
He is not suggesting drilling out a bigger hole in the anchor   
He's not digging himself into a hole trying to prove an incorrect point for others in the forum to read. He's just simply misinformed regarding his whole statement. 
And Ringtail, I'm not having a crack at you. I'm having a 'crack' at your misguided views you are stating in this thread. 
And who made you the building god where the buck stops? You fail to heed your own advice: "If you don't like what's typed above or the short to the point way it's typed, please, simply ignore it." These forums are for 
people to ask questions and convey experiences to which the original poster can make up their own mind. It doesn't need people going out of their way to prove others wrong. You are basing your whole arguement on a single technical brochure posted by someone you don't even know. For all you know the next 10 brochures could state the need for the gap. Engineer's aren't always right and the last deck I had engineered I found a mistake by the engineer for which he had to make changes. 
QUOTE]

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## ringtail

x 2 stevoh64  
 [QUOTE=Stan 101;843156][QUOTE=ringtail;843086]
I'm not the one recommending to disregard manufacturer's spec.  *The manufacturers spec is for uplift only. If you need to achieve this amount of uplift resistance then you must place the post on the cross bar. If the amount of uplift resistance required is less, moving the post is totally valid.* Where edge distance comes into play.  *Naturally, and holes are located to suit the application. I’m not talking stirrups here * 
  I have no idea what you are referring in the above quote..  *If a engineer specs gal nails and I substitute ss nails because they are a better product am I ignoring the advice of the engineer ?* 
and therein lies the issue you seem to be avoiding in your replies. Tyre pressures are a 'recommendation' The Pryda Post Support spec is not a recommendation. It is an installation spec that is to be adhered to to the letter. That's the part you can't seem to come to terms with.  *No it is not. It is a installation guide that gives parameters to be followed in order to achieve a desired result  The design loads tabulated above require that: (a) the timber post must bear on the Post Anchor base and
(b) all posts must be a minimum of 90x90 mm section* *This is copied from the pryda site - read it very carefully. It is repeated for all of the stirrup types. No where does it state that the post must bear on the cross bar at all times. It does state that to achieve the design loads in the table the post must bear on the cross bar and be 90 x 90 min. Big difference there.* *INSTRUCTIONS FOR INSTALLATION* *These notes are provided to ensure proper installation.
1. All fasteners used must be manufactured by reputable
companies and be of structural quality.
2. Connectors must not be installed on timber which is split before
or during installation. If the timber is likely to split as fasteners
are driven, fastener holes must be pre-drilled.
3. Do not overload the joints- during construction or in service.
4. Bolt hole diameter must be 0.8 mm to 1.5 mm larger than the
bolt diameter and the specified washers must be installed.
5. Use proper safety equipment and due care in installing these
connectors
6. Any gaps in joints between the timber members must not
exceed 3 mm
7. Do not over-tighten screws. 
Above are the installation instructions copied from the pryda site. There is no mention that the post must sit on the cross bar.* 
Because the guidelines for installation have been either misinterperated, or missed all together by your certifier / engineer does not make it right and is no rational point of recourse for you. Ignorance or disregard now the facts have been pointed out to you is no excuse. *Again, maybe it is not required in non cyclonic areas as the stirrup is so strong and provides so much resistance to uplift that engineers and certifiers dont pay any attention to the installation other than 75 mm clearance for termites and has the correct minimum embedded depth into the footing. The facts you refer to are only relevant if you need the required uplift performance from that joint.* 
I've already told you; edge distance. You're a carpenter. That should be in the forefront of your mind. *I am a qualified carpenter, qualified welder/steel fabricator and qualified motor mechanic and a member of the society of automotive engineers. * 
He's not digging himself into a hole trying to prove an incorrect point for others in the forum to read. He's just simply misinformed regarding his whole statement. 
And Ringtail, I'm not having a crack at you. I'm having a 'crack' at your misguided views you are stating in this thread. *No, he is agreeing with me that placing the post off the cross bar is sound building practice* 
No, the onus on you is to prove Pryda wrong. Their product is already independently certified. *No, you made the accusation that I violate the Building Code of Australia - prove it * 
  So isn't that an issue of your certifier being a little flaky on his form 15 requirement if he is passing the project without one. I'm sure Pryda would be happy to offer form 15s. They do whenever requested, however the onus is not on them to supply the form 15 without request. *Not really. Where do you stop - form 15 for nails, bolts, washers, timber, joist protectors etc...they all play a vital role in the quality of the structure yet it is impractical to request form 15's just to cover ones @@@@@*  *Maybe because Brisbane is a non cyclonic area uplift it is not an issue - I dont know how the certifiers work but I do know that Cherub65 (in post # 14 ) is the first person I have ever heard of having this issue with an engineer or certifier* 
Anyway, I've spoken enough on this. Any rational person reading this thread will now, hopefully not be sidetracked into disregarding installation guidelines.  *Nice chatting with you*

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## cherub65

> You are basing your whole arguement on a single technical brochure posted by someone you don't even know. For all you know the next 10 brochures could state the need for the gap. Engineer's aren't always right and the last deck I had engineered I found a mistake by the engineer for which he had to make changes.

  Stevoh, That PDF I posted is a link to Pryda's website. I didn't underline must bear on post, they did. And they have done it on every page, go figure.

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## r3nov8or

When in PrydaLand, do as the Prydians do. 
When in GBCLand, do as you like unless you can, unlike me, find anything whatsoever to do with GBC post supports or their specifications or capabilities. 
EDIT : When in GCBLand, do as GCBians do.

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## bpj1968

> ...... It also says that those high wind stirrups should not be used to support a post that has balustrading attatched to it - what bollocks. .....

  They say it for all their post stirrups 
"Post anchors unless approved by a registered structural Engineer, shall not be used to support balustrade support post." 
That would relate to using it for a _balustrade post only_, such as at the edge of a concrete verandah

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## ringtail

Sorry guys it not GBC. Its GCB  Glacier Ceiling Battens P/L are your ceiling batten and building supplies specialists. Ceiling Battens Qld Australia 
page 8 of the cataluge gives suggested installation methods.

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## r3nov8or

Can't help thinking that post would have been handy at around #7  :Smilie:

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## ringtail

Better late than never r3nov8or. As the debate sort of revolved around the pryda product I sought of focused on them a bit - amongst other things. Anyway, they are good products and a handy catalogue to have downloaded.

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## r3nov8or

Yes, they have some handy looking products, but they've advised they retail only as far south as Sydney...

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## ringtail

Thats a bugger mate. We cant let ya have all the good stuff though. Maybe convince a builders hardware down there to stock them

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## stevoh741

All quiet on the "Stan 101" front now?

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## ringtail

Indeed.

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## ScroozAdmin

Just to come in on this from a slightly different angle, all manufacturers who quote load data do so based on testing normally carried out 'in house'  or if they are confident they will allow an independant testing house to complete the work. Either way this data is gathered under strict test conditions which is usually completely irrelevant to site conditions and there will probably be a rider in the docs to support this. Ultimately the data should be seen as guidance only and not the strict performance data that most engineers/specifiers assume it is (occasionally to there cost unfortunately). Generally the manufacturer would include a large safety factor in the data to allow for the many site variables but ultimately the only true way to get the definate loads for any product is by site testing followed by the suitable calculations. 
In the case of the Pryda data they are using fairly outdated calc methods and the specs are not particularly detailed, I couldn't see any safety factors which is a major concern, nor does it spec which fasteners to use properly (M10 bolts means nothing, grade?) and I certainly wouldn't use ankascrews (they can and do vibrate loose under certain conditions you know) on a structural joint although Ramset and Pryda are the same company so I guess that's an obvious link. 
The upshot is that manufacturers data will always be just a guide and you should make sure any connections or installations are approved by an engineer on site, and you must understand the difference between ultimate loads (the failure point) and working loads (with a safety factor included, normally around 3).

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## chrisp

> In the case of the Pryda data they are using fairly outdated calc methods and the specs are not particularly detailed,

  In fairness, you weren't comparing the two products, or their suggested installation methods,  But what is the engineering information and standards quoted for the two brands mentioned in this thread? 
The Pydra information states:    

> CODES & STANDARDS
> Product design capacities in this guide have been derived from:
> (a) results of laboratory tests carried out by or for Pryda Australia
> (b) engineering computations in accordance with the relevant Australian standards, ie:
> * AS1720.1-1997 Timber Structures. Part 1: Design Methods
> * AS/NZS1170:2002 Structural Design Principles
> * AS4055 -2006 Wind Loads for Housing
> Reference is also made to AS1684.1-1999 Residential Timber Framed Construction - Part 1: Design Criteria.
> Design capacities tabulated in this guide apply directly for joints in houses and on secondary beams in other structures. For joints on primary beams in structures other than houses, reduce the capacity as specified in page 4 (if applicable). Design capacities are related to the Joint Group of the timber as defined in AS1720 and AS1684. If the joint group of timber members joined together varies, the lower group must be assumed for design, eg: JD5 is lower than JD4.
> Load Duration Factor for Wind Wind Uplift capacities are based on the AS1720.1:1997 (Amdt No.4 Nov 2002) using k1=1.14, for use in conjunction with AS/NZS1170:2002 loading code

  GCB, on their web site only provide engineering certificates for two of their products - and they aren't post supports.  See Glacier Ceiling battens Specifications and engineering documents. Building suppliers for roofing and ceilings. Wholesale building Products Qld.

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## ScroozAdmin

> In fairness, you weren't comparing the two products, or their suggested installation methods,  But what is the engineering information and standards quoted for the two brands mentioned in this thread?

  I wasn't trying to compare them, just generalising tbh, I see lots of quoting of standards and codes on the forum which can easily lead the amateurs and non experienced into potentially dangerous practices thinking a product or a detail is fit for purpose when it might not be, so its important to understand: 
a) most standards are general guidelines which are completely open to interpretation and irrelevant to specific tasks.
b) manufacturers load data is usually arrived at through lab testing and is *never* specific to your site conditions.
c) if you are using load data or standards as a basis for selecting products make sure you know what it actually means.

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## Stan 101

I have been requested by Ringtail to do the following:    

> I would ask that you post on this thread (in the open forum) a statement as follows:

  So I am happy to offer the following statement supplied to me by Ringtail.  
   In my post on this matter (number 28) I made a reference in a  response to Ringtail   to your blatent (sic) disregard for building  codes and the engineers who designed and specified the post support in  question and then passing it on as fact on this forum for DIY people to  read.
  I apologize for this statement.  I did not mean to imply that Ringtail  has disregard for the requirements of building codes either in work  Ringtail does in relation to fixing posts to stirrups or generally in  work Ringtail undertakes and I have no basis for any such imputation, or  to comment on the quality of Ringtails work or any knowledge of any  job Ringtail has undertaken. My intention was only to express my views  as to the desired practice (in my opinion) for fixing posts to the Pryda  stirrups. I did not also mean to imply that Ringtail is reckless or  does not have due regard for how information posted on this forum may be  utilized. I also acknowledge that the job around which this discussion  centered was not a job of Ringtails.   
Ringtail has assured me that once I post this statement sent to me., The matter will be closed. I will take him on his word on this. 
I've requested that my account be closed from the administration. Thank you to all that have assisted me and thanks for the personal messages of thanks. 
Enjoy your renovations, team.

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## cherub65

Wtf?

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## Stan 101

In regard to the OP's question. I will making an approach to Kevin Skause of the AIBS to have this topic brought to their member's attention in August.  
Over and out.

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## ringtail

I  wish to advise everybody that this course of action was only taken (after receiving advice)  to protect my business interests. I in no way have requested that stan be removed from the forum and I think it is a shame that he is leaving. As promised, this matter is now closed.

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## r3nov8or

It is a sad day  :Frown:

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## chrisp

> It is a sad day

   :What he said:

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## Jack-the-Hammer

When a forum such as this ceases to be fun and informative and become serious with legal actions, it's time to sign off and so this will be my last contribution to this forum. Ciao.  :Tears:

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## watson

Without "getting up" anybody.....that's what the Reporting system is all about.......No need for things to get this far. Report posts and action can be taken.

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