Building Regulations 2006 - Tie-down & Support of beams?

[thebuildingins]

Hi guys,
Long time reader, first time poster. The information on here is first class and finally I have my own question for you to peruse.
<O
Anyway, the reason for my thread is this. I’ve been a registered Building Inspector
for almost 25 years now have never been able to establish concentrated loading requirements for single sideways jack trusses supporting king posts or rafter creepers.
<O

Evidently, the tie-down requirements are skewed nails with double noggin heads and minimum 25mm penetration for soft wood and 15mm for hard woods, however, what is required to support the concentrated load? Should I enforce a triple studs supported via a reinforced strip footing with stumps or use a brick pier supported by a pad footings?
<O

Commonly, I required a laminated stud fixed the concrete edge beam. This has never failed in 20+ years, however what is the official regulation/mandatory fixing and support?
<O
Should I get a Form 15 for this?
<O
Thanks in advance.

[ausdesign]

If I understand the question correctly then I'd use 'studs supporting concentrated loads' to be able to input the area of roof supported & yes direct the load onto the footings.
Out of curiosity - where did you get those nailing details from ?

[silentC]

Wouldn't you just go by the engineer's design? If he specs it then it's his problem if it falls down. So I would refer to the engineer's drawings and make sure it complies with that. They all have their favourite ways of doing things and it's up to them to interpret the code.

I guess what I am saying is that, with all due respect to building inspectors, I want my building's structure designed by an engineer who has been appropriately trained in structural design, not someone who is "familiar with the code".

I once had an argument with a BI in Sydney because he disagreed with the engineer's design of my slab. We lodged the plans and they were accepted, then we dug the footings, put in the steel, and this guy came out and wanted to argue about it. I said it was all done according to the plan and, with all due respect, if I'm going to pay a consulting engineer to design something, why would I disregard his advice because a building inspector disagreed with it? In the end I had to get the engineer to speak to the BI to 'satisfy' him. It begs the question why do we need engineers when we have BIs who know it all?

[thebuildingsurv]

what the ? do you mean a girder or truncated girder truss. Creepers and jacks do not have that much load on them. Man you are confusing me or you are way just otta my league. We need building inspectors like this one to baffle us with tech talk, if we just used engineers for inspections you would have to wait for them to go back to the office to make a descision based on a mathematical formula, or just go way overboard.

[ausdesign]

i hear where you're coming from silent.
I tend to use engineers the least I can in residential situations purely because of the fees they tend to charge but more importantly because most situations can be covered by the timber framing code, steel tables, manuf. specs etc.
Even slab designs, unless they're outside the scope of AS2870 - Residential Slabs & Footings - can be provided without certification.
If an engineer is engaged then I haven't come across many BI's or a BS's that would question their comp's. but then again I now have a notation on all our drawings that 'no alterations are to be made by Councils, Contractors or any other persons without written prior consent from AusDesign' due to a BI who Ok'd structural alterations onsite & nearly cost me $13500 because he thought he knew better.
I suppose at the end of the day they're all out there including building designers who make mistakes.

[silentC]

I used a designer for my place and he did the floor design using the LVL software but still wanted to use an engineer for the footings. He's probably just lazy The roof, of course, is designed by the software from gangnail or where ever. I suppose I paid about $2000 for the engineer, which included a site visit to do a variation on a slab design. I figure it was worth it because if there were or are any problems, it's covered by his indemnity (assuming we follow his design).

When the BI from the council came out, he saw the engineer's name on the plans and just went "right, no need to look at that". It's all about a smooth path. I'm happy to say we had no dramas with inspections and had compliments from the two guys who did come out, which is a bit rare I have found.

Yes they can go overboard. I know of a job that the builder reckons cost $100,000 and 6 months more than it needed to because of an overly cautious engineer. It was a two unit town house!! I would have been p'ed off to say the least.

Anyway, sorry for the outburst. I suppose I just worry about BI's 'interfering'. I know they have seen it all. It's just that if they say "yeah, do it that way" and it turns out to be wrong, what is the come back? Especially if you changed the engineer's or designer's design on their say so. I used to ask our BI "how do you reckon we should do that?" He liked being asked but usually just said "your engineer will tell you"

[ausdesign]

I couldn't agree more with your post Silent.
I don't know if I would have forked out 2 grand for the engineer but then I don't know the fulll circumstances.
I was going to write an in depth reply about . . . .
People need to know that 'experts' in the building industry are 'few and far between' & many that purport to be experts are not. . .
but I'm getting to the stage where i'll leave it to someone with more PI insurance to say . . . . .