who does the design for wall bracing layout ?

Need help please ,who does the design for wall bracing layout ?
engineer or prefab trusses manufacturer

Haha I'll try and avoid the conflict from the last thread.
The truss manufacturer will do the bracing layout assuming your getting prefab walls. An engineer can do it if requested and occasionally draftsman will include it in there drawings but from my experience building inspectors aren't happy until they get a frame layout with bracing locations on it. The truss manufacturer shouldn't charge you any extra for this but you will have to give them the go ahead for the frames. Hope that makes sense.

nomad ,

thank you for your reply .

if they have not provided you with one, there should be a KN rating on each direction that the house needs to be braced to.

From this you can then add bracing in each direction spaced out around the house to the required bracing.

Keep in mind that items such as Gyprock will provide nominal bracing, so you do not need to go over the requirement.

Wall Bracing, along with tie/hold down details should be provided by a structural engineer... Or at least signed off by one...

The certifier, before approving the application, should want to see the calculations, with kN ratings, and the recommened bracing requirements, with layout for each area of the house...

A strutural engineer will work to AS1684 to assess the extent of bracing, and then work with the designer to locate the necessary bracing...

The detail drawings should also provide details of the bracing, with AS1684 clauses if applicable, and fixing details i.e. nailing requirements...

A structural engineer should be around $500 to have this done and signed off, with concrete slab design included!

These can also be calculated from your states building code. You need to know the area of of the walls and roof, as well as the wind rating.
Any good draftsperson or first fix carpenter should be able to work this out for you.

Must be by an engineer - either an independent one or from the wall frame manufacturer. Their frames are all engineered designed programs so if they provide the computations then it is still deemed to be engineered. Don't rely on the carpenter to work it out...it is (unfortunately) far too complicated these days and while the carpenter may be trying to help, you could be landing him in a heap of hot water if the frame gets knocked back.

As Builda said must have engineering signoff to be deemed acceptable...also you have someone's PI insurance to sue if it goes pear shaped...

I acknowledge it is different from state to state, but in SA, these calculations are a compulsory part of licensing and completing the TAFE unit of the Timber Framing Code (AZS1684 - an Australian Standard, not a state specific document) , and all licensed builders are expected to be able to work them out.
The calculations are quite easy (any good year 10 should have the skills) and requires little more than calculating the surface area of both the front and side of the house, and knowing the wind speeds in the designated area (Section 8 of the code).
From there you look up the required bracing required and choose the types and areas necessary to give you the required number. It is no harder than working out the size of a hanging beam.

While that is true, as the other poster said, if an engineer does it then it is all covered under a PI insurance policy. Anyone can read the Australian Standards and design Concrete Slabs for example, however ONLY an engineer is actually qualified to design them. As with everything there is no problem until something goes wrong and for Owner Builders there is enough day to day issues that can go wrong without setting up some of these issues.

I agree, anyone can actually read the standard and design it but the fact remains that only an engineer has the legal authority (if it ever gets to court) to sign off on the design.

...and further from Builda's comment not every engineer is "automatically" licensed to this sort of work as they must be a Registered Building Practioneer... http://www.buildingcommission.com.au/ww ... he-bpb.asp

The BPB is an independent statutory body established under the Building Act 1993. It oversees the quality and standard of professional services in the Victorian building industry. In doing so, it administers a registration system and monitors the conduct and ability of registered building practitioners. The Building Act 1993 requires most people who work in building, to be registered as building practitioners with the BPB. Registered building practitioners are generally required to carry the appropriate insurance to provide consumers with better protection. The BPB registers individuals not companies or businesses.

Whilst as an engineer I've done structural computations for various types of large structures and know the various codes, work classified as "building" work has needed to be signed of by a RBP.

And this is an Australia wide requirement...

Sorry, not wanting to start a flame war or anything, but that comment is crap.
Legal authority is not limited to an engineer. A Registered Building Practioneer, or an apropriatly licenced builder, can also perform the calculations. In the event there was a problem an independent expert would be asked to confirm work was performed to the appropriate standards (AZS1684.2 for timber frames in non cyclonic conditions - to be specific)
The standards are there and must be met, unless you are licence to work outside of these boundaries (i.e. an engineer) (and are overly engineered to allow for defects and discrepancies)
Likewise, footings needn't be done by an engineer in some cases - (and the building code specifies these and the size and type of footing to be used.) The reality is that an engineer would most likely put in a less bracing or smaller footings and have PI to cover themselves if their figures were found to be in error. The appropriate codes set out the sizes, types etc that are required and have a reasonable fudge factor built in to allow for defects/poor installation/and other variables.
Sorry to tell you, but building a house isn’t rocket science.
By all means use an engineer (many do, including myself for footings) but in SA at least, and by my reading of the (National) standards it is not essential for most residential properties.
But please, don’t take my word for it (I am a licence builder.) Call up the HIA or other appropriate bodies and find out for yourself.
At the end of the day, and engineer or builder may work out the figures, but if the installation isn't up to standard it was all a waste of time (no skin of the engineers nose, he will blame the contractor every time)
Back to the first post, elchagie, are you submitting your own plans or going with a design from a builder? If its the latter, then the draftsperson and/or engineer will probably work this out for you to submit to council.

I was going to comment on this massive generalisation...

but you've done it for me...

Hills Guy, while you may think my comment is crap, do you have legal experience of what actually happens in a court if one of these issues gets tested?

Any one with a year 8 education can read the standard and 'interpret' it how they see it but if a non-engineer does this and there is a problem then you are in big trouble if it ever gets to a court. From my experience it is better to put that legal responsibility back on the engineer - it is just not worth the risk.

For the home owner, my advice is to pay the $150 and get the engineer to do the design. Peace of mind is cheap at that price and I would never advise a fellow carpenter to put their neck into a potential legal noose by taking this design on themselves. 99% of the time it will be OK, but it is the 1% that will ruin you.

Stupid question (or trivial) for some ... but ... how do I know if a certain wall is a braced wall??? What am I looking for? The big metal crosses across the whole wall? Or thin plywood boards stuck on some sections os external walls ? Or both??? Can the top floor walls also be braced?? Thanks.

BTW, our frame layout (which we got from the manufacturer) does not have any of this on the plan. Shouldn't it be shown?? As well as spacing of the vertical studs?? It only shows where the frame goes (numbered pieces of wood), and doors and windows!!
Oh, and marks some wood as "B type cross", "A type angle" or "smart joist xyz", or "HBx" or "HAx" (where x,y,z are some numerics).
It also ignores the steel placement - or, does the frame plan refer to timber parts only?
Thanks!

Sorry Mate,
Speaking only for myself as a draftie here...
Any good draftsperson would gave the good sense not to work out anything structural on a build.
'Refer to Structural Engineers drawings and specifications' every time.
While it may be of great assistance to builders and owner builders for me to do it, I refuse every time.
First thing that happens everytime theres a problem....Blame someone...then...sue someone!

Ive said this in enough posts now, dont be a hero, use the professionals.
A structural Engineer may cost you a few hundred bucks.....the risk of not using one may cost you many thousands of bucks.
Just a thought,
Pat.

Im watching, so play nice

...there's hardly anything to "watch"...

But I watch everything TDL... you should know that

Any ideas on my wall bracing queation? Maybe some kind of a manual that I was unable (too busy/lazy ) to find myself ??