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Development Approval Systems: codes of practice and human behaviour

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Some further background on South Australian system:


Development approval comprises in South Australia comprises of:

1) development plan consent
2) buildings rules consent

Taken together, with maybe some additional conditions outside these two
categories development approval is granted, and building permits issued.
This system introduced with the 1993 development act and regulations, which
basically distances the councils from any responsibility.

The system has changed but human behaviour hasn't. As I understand prior to
1993, it seems to have been common to simply draw up some plans and take to
council: and council would tell the building proponent what was required for
approval. Not sure how it relates to the engineering, but for the simple
they may have done that in-house or had some prescriptive solutions
available not otherwise made public. Anycase councils are not allowed to do
that any more. There is fairly strict enforcement of independence. Persons
involved with ant aspect of the design are not permitted to be involved in
the assessment and approval.

The act also brought in private certifiers and certification for building
rules consent. A lot of councils reduced their building departments, and
outsource building rules assessment to the private certifiers. Once a
private certifier has been appointed they cannot be removed from a project.
The benefit of private certifiers (registered building surveyors) is
consistency with respect to the building rules. The same design put into two
different city councils may get approved by one and rejected by the other.
If a market builder and put the same buildings all over the place then
private certifier only has to look at the differences relative to the site.
Whilst each city council would look at the entire proposal each and every
time. Few manufacturers however have got the idea.

Building surveyors are supposedly unrestricted in what they can assess,
whilst building survey technicians are limited. Technicians require that
calculations are certified by an independent technical expert, however most
building surveyors tend to take this approach aswell. Local councils and
private certifiers tend to have on going contracts with consulting engineers
to act as indepenedent technical expert. Once again if go through different
city councils can get inconsistencies in the engineering assessment. Which
can be a good thing, but the focus is delays: got approved last week by
council X, but rejected this week by council Y. Now city councils may ask
for engineering calculations or a certificate of an independent technical
expert.

Now if someone turns up with a drawing of a say a garden shed. Can simply
look at the drawings, conclude that done multitudes of such, and simply
issue a certificate of an independent technical expert: as the
evidence-of-suitability. However, if the proposal is non-compliant and need
to specify what is required to make it compliant then loose status of
independence, and have to submit the detailed calculations.

The problem is that people in general, including builders and others that
should no better, still go to council expecting council to tell them what to
do. The city councils are accused of being slow and causing unnecessary
delays. So they played a game of stop the clock. Recent changes have reduced
their ability to play this game. They would receive the development
application make a quick review, and issue a request for further
information: stopping their clock. The applicant is given 3 months to
respond. Even though point 1 is typically no prescriptive solutions and
point 2 provide engineers calculations. The applicants spend 3 months
passing their application back and forth to council playing architect,
resolving the 3 to 4 pages of issue they have. Seeking the engineering in
the last week.

Part of the pyschology on the part of councils, is that they cannot ask for
architects drawings, but if they ask for engineering calculations there is a
good chance of getting some decent drawings. Unfortunately the client only
want calculations, because that is all the council asks for: and they are
reluctant to pay for that: since they figure that council should just tell
them what is required: or simply approve. After all they can see similar
structures all over the place: so what is the problem?

There are constants compliants about the city councils, being slow, causing
unwarranted delays, and otherwise being unproductive and inefficient. The
state planning authority keeps tweaking the system. But the system is not
the problem: human behaviour is the problem. Insantity keep repeating same
action and expecting different results.

As I see it the building code of Australia, the australian buildings codes
board CodeMark scheme, and the South Australian development act and
regulations, all provide for an efficient system of operation. And all would
be efficient if people through out the system got the idea how to use the
system efficiently. 

But there are internal politics. There was resistance by council employees
when new act came out, since councils started to cut back on size of
building departments. Though many were already outsourcing engineering
checks. The act also basically eliminated council inspections of building
works, the rise in defects used to try and convince community to give
control back to the council. However that did not happen, a minimum 20%
inspection of applications was imposed as a responsibility. Some argued
couldn't provide or needed to increase application fees, but was dismissed
by reference to those councils which had retained their inspections.

QA is some what misunderstood in building industry. They remove inspections
but don't replace with anything to ensure compliance. Similarly there is a
lack of check and balance on the certifications of independent technical
experts.

Inside a manufacturing organisation, not subjected to external regulation
except by market forces, the operating procedures, and design methodolgies
can be changed on a regular basis, with internal information and training
programmes also taking place. All the people involved contributing to what
the changes are to be.

The building industry however is controlled by external forces. The building
surveyors, and councils do not design they only make assessments and grant
approval. They do not have to find design-solutions for all the potentially
conflicting code clauses. Also the codes only take into consideration the
performance of the end-product, they largely ignore the processes of:
design, manufacture, handling, transportation and construction.

In effect every building is a real world experiment. No physical prototype
has been built and had thousands of hours of testing, to validate the
mathematical models employed. If make a mistake with mechanical calclations
on small scale products, likely to find out when test. So design errors some
waht minimised. But no accounting for rubbish getting made, installed and
distributed, with need to recall.

Fundamental to structural design is the guess of the loads, and assignment
of the load to be designed for. No matter how complex the methods for
obtaining it is still a guess, or a subjective judgement as to what it
should be. At the end of the day the design load can be exceeded and the
building can collapse.

So not much point increasing complexity of the models, to try and hide the
guess or hide subjective judgement. Its not really the relative difference
between the magnitude of load and resistance that should be of concern.
Rather the mode of failure should be of concern. People are not going to be
happy if told have earthquake resistant buildings, and they experience an
earthquake beyond the design loads.

The human perception of safety, risk and personal responsibility need to be
addressed. QA tries to avoid assignment of blame, rather looks for what in
the system permitted a defect to occur.  A defect may be a consequence of an
individuals actions, but what caused them to take that action, or what
caused them to be in such a job position? They say that 80% of all defects
can be attributed to 20% of all causes.

You can force changes to human habits, but under pressure originally formed
habits tend to be dominant. For example I have no problems with my car
indicators most of the time, have a bad day, and I am turning wind screen
wipers on. Shifting location of controls is not good. Builders follow
routine, throw something out of the ordinary in, and they are likely to mess
it up. All kinds of issues then have to be resolved during construction.
When the likes of Telford built small scale prototypes, not just testing
end-prooduct but also testing the construction process.

Whilst buildings are typically custom designed and built, there is still
routine in the procedures that I don't beleive is getting the design effort
required. This doesn't just result in defects getting into the building but
also leads to accidents during construction. The construction processes need
to be more quality robust. And the design and approval processes more
quality robust.

Whilst there may be new research that requires changes to the building
codes, changing the codes contributes to the defects in the buildings,
because the systems that use the codes are not quality robust enough to
handle the variations introduced by the codes.

Here some 80% of buildings are simply drawn up by building designers, or
rather plan drafters. A large number of buildings are also owner built. The
plan drafters build a reputation for getting development approval, and take
on more and more complex buildings. And the community thinks that all that
is required for approval is a picture of the proposal. They haven't yet
quite got the requirement for evidence-of-suitability: and the onus is on
them to prove suitable. Also most buildings exist already, so main issue is
not new buildings, but modifications to existing buildings: especially
modifications which take place without approval.

Attachment of carports and verandahs to houses a problem. There is a
prescriptive construction guide for timber canopies, maximum span 4.2m. This
guide indicates requirement to be compliant with AS1684 timber framing code.
Builders concept, find out when house built, complies with AS1684, therefore
can attach any size verandah desire to existing. Not what the clause meant.
It is advising that the timber house structure needs checking against
AS1684, taking account of the additional load imposed by the verandah. The
house structure needs to be strengthened, and additional tie down provided.
Multitude of problems concerning practicalities of such tie downs and its
actual installation, and variations in councils assessment. Most of the
additional rafter tie down useless since wind will just rip top plate of the
wall studs. The populations however, basic view we don't have tropical
cyclones: so requirements are excessive. Though roofs damaged every year by
wind storms less than the design wind load.

Quantitative Structural design is entirely dependent on qualitative
judgments on the magnitude of input parameters. I believe currently more
time needs to be spent on improving the qualitative aspects of the design,
rather than the mathematical models. Things are getting out off balance,
qualitative is being lost to number crunching. What is it that the people
really want? Does all the building structure need to resist the same design
level event?

As far as I know most coldformed steel sheds have defective connections:
16mm end plate bolted to column flange less than 3mm thick. But been getting
approval for some 30 years, and few recorded failures. The issue isn't
really that they will fail, but rather when will they fail? If there is a
wide spread strengthening campaign, at great expense, the issue will still
be when will they fail? If the design level event is exceeded the day after
strengthening there will be a lot of unhappy people.

If codes are changed then implication that existing are flawed in some way.
So the real issue is environmental monitoring and warning. During Tropical
Cyclone Yasi, the general messages going out on twitter and the news were
wind speeds that exceeded design wind speeds. Yet people were being told to
take shelter in their houses, though some were evacuated. What is the
community response when the design level event exceeded? And isn't it better
to get familiar with responding, than become complacent that never going to
be a problem again, and can cut back on emergency services? The insurance
payout problem is too far great a component of the decision making. Further
controlling mode of failure provides less hazardous system than increasing
resistance to higher and higher loads. Better assessment of the magnitude
and type of loads a structure experiences is important: but less important
than how the structure behaves when the design load is exceeded.

Also locked into the buildings we have by the inertia of peoples
perceptions, and council planning requirements. That is hindered from
building a hitech house. Also manufacturing and construction processes
hinder moving forward. Not all that much real engineering in building and
construction: the infrastructure for supply not really highly developed due
to fragmentation amongst many small businesses.

One car factory can produce 100,000 vehicles: that is private enclosures of
space, every year. Can one building contractor do that? One billion people
in world in need of shelter, and we are messing with mathematical models to
say what was acceptable last week will still be acceptable next week. And
given that humans have legs, not roots, why do we construct dwellings
anchored to the ground. A lot of the problems we have are because buildings
are anchored in the wrong geographical location. Its crazy!

One way around the building codes, and cost of land: Ships! Factory ships,
hospitals, schools, offices and residences. Water 2/3rd of planet, land
1/3rd: plenty of solar. Cabin in ship, or box in skyscraper? Ships can dock
together in middle of ocean and exchange goods. Doesn't the USA have a
massive graveyard of unused ships? Minimise problems of geographical
unemployment. More efficient factory typically gets built in new country,
shutting old factory down: creating unemployment. But with ships, personnel
just change ship. Aircraft are fast, but lost something relative to the
merchant navy. The global village would be a lot smaller with ships spanning
the oceans. Also changes the politics of international aid. Population not
contricted to barren wasteland if skylifted to a floating city.

But I'm diverging as usual.

regards

Conrad





















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