Detailed Engineering Evaluations….. DEE’s

Ah ha, finally, some one is talking about the Detailed Engineering Evaluations (DEE’s.)  Now that has taken nearly 3 years.

Link Here: http://www.stuff.co.nz/the-press/business/the-rebuild/9200180/220-Chch-buildings-urgently-closed-by-Cera

This is an issue that has caused us massive grief.  By my calculations there are over 10,000 DEE’s required in Christchurch.  There are approximately 60 Structural engineers in the city.  Each DEE takes a full weeks work and that is for a “simple” building like ours. We are not talking multi storey stuff here!  By my calculations, that will mean it will take approximately 3.2 years for the Engineers to do the ones that are required now. ( And i believe that now every multi story unit in the city will need a DEE- that should bring the figures up to 60000??? that’s a guess by the way!) That leaves the Engineers no time to design solutions or any other foundation work. Which is what they should be doing and is what we desperately need in the city.

(Incidentally CERA has been waiting for our DEE for over 2 years??   even I can not remember any longer. I believe it is imminent, but I would say that wouldn’t I)

The other option to a DEE is a IEP. (Initial Evaluation Procedure) For those of you wanting to dig deeper: Link here: http://www.dbcon.co.nz/structural-engineering/the-iep-and-earthquake-assessments-how-the-process-works/

In a nut shell:  DBCon Chartered Engineers has this to say about IEP’s:

“This was devised as a filtering tool to see which buildings warranted further investigation. Unfortunately it has become a defining test. We say unfortunately, because it is a very crude procedure. It is based on the age of the building, the materials used, the type of soil, and a huge fudge factor at the end. The output from this procedure is a percentage of the New  Building Standard (NBS), which is the earthquake resistance you would expect that from a similar building, built to today’s requirements. Anything less than 33% is deemed ‘earthquake prone’, between 33% and 67% is called ‘earthquake risk’ and above 67% is considered satisfactory. We are finding that most buildings built before 1970 go straight into the earthquake prone category.”

“If the earthquake assessment shows some strengthening is required of the building, then the strengthening will need to be designed. However, it is a challenge to the Engineering Profession to design this strengthening work as an economic solution that allows the building to continue in service and still pay a reasonable return. Unfortunately in some of the smaller provincial towns this may not be possible. The rental income from a two-storey brick-built building may not justify the expense of strengthening it. I have heard that if the strengthening work is more than 33% of the value of the building, it is better to demolish and rebuild. Both repairs and demolition may be difficult or impossible for Historic Listed buildings.

“Generally speaking single-storey buildings are relatively cheap to strengthen if required. The presence of  unreinforced masonry (old brickwork and block work with no steel reinforcing) makes strengthening more challenging.”

Thank you DBCon for a very clear and simple explanation.

So, we have a situation is Christchurch where it is nearly impossible to get a DEE out of an Engineer (and by the way no 2 Engineer’s can agree on the DEE’s anyway. Ask 6 engineer’s and get 6 different figures, this has occurred in Greymouth recently) Chances are also that CERA will reject your DEE if it is not “acceptable” to them, this is also common practice for them.

Cera pulled most of the city down on the Basis of IEP’s,  often done by observations from the street with no detailed checking done.  A unreinforced masonry building is automatically graded at approx 9-10 % of the NBS.  And thus CERA decided in its wisdom that these buildings were unsafe. The logic was flawed and the engineers lacked training and experience.  (Or was it some grand plan???  we will find out in the future!)

There has to be a solution and some middle ground found here.   My understanding is that some Engineers in the city are deliberately not doing DEE’s for some buildings as they do not want to unnecessarily evict the businesses in them.  This has been a bone of contention for some time.  We are a good case in point. Needlessly chucked out of a building strengthened to 73% of the NBS.

incidentally I mentioned this issue to the CCC Crown Manager (Doug Martin) on Thursday last week. He was unaware of the issue.

http://www.ccc.govt.nz/homeliving/goaheadbuildingplannings00/bcactionplan/index.aspx

(On 15 July 2013, Doug Martin was appointed Crown Manager to the Christchurch City Council as a result of International Accreditation New Zealand (IANZ) withdrawing their accreditation for Christchurch City Council to issue building consents.

The Crown Manager’s Terms of Reference requires an action plan to be developed to make sure that the Council has the correct systems and processes in place to enable the Council to be accredited as a Building Consent Authority.”)

Ho humm. I must confess to being tired of their inflexibility.  May be if they employed some one with decent brains in control of CERA  we might get some sense out of them.

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