Category: QuakeStar

QuakeStar is an incorporated society formed to establish and operate an earthquake rating scheme for New Zealand buildings, including houses.

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New: Get a QuakeStar rating for your house! (trial version for NZ houses)
HouseCheck is an interactive online tool that lets you see how your home may perform in a major earthquake.

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Update: Resilient Buildings for NZ – Who Cares? A Call for Action

The aim of QuakeStar is to improve the management of earthquake risk in the property industry by providing owners, tenants, users and the public a basic means to distinguish between buildings on the basis of assessed earthquake performance in terms of safety, damage and repair time.

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QuakeStar Rating	Risk of Harm*	Damage	Repair Time
★★★★★	Extremely low	Minimal	Days
★★★★	Very low	Moderate	Weeks
★★★	Low	Significant	Months
★★	Moderate	Substantial	> 6 months
★	High	Severe	> 1 year

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Modelled on the United States Resiliency Council Ratings system with a 500-year shaking intensity. *Safety (Risk of personal harm).

• QuakeStar improves the consistency and accessibility of building reporting
• Buildings with higher design standards, score higher star-ratings
• QuakeStar records vital earthquake characteristics
• QuakeStar is indicative (and not predictive)
• QuakeStar provides a basis for the comparison of NZ buildings
• QuakeStar synchronises with %NBS (but with advantages)

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QuakeStar is an incorporated society formed to establish and operate an earthquake rating scheme for New Zealand buildings, including houses.

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The aim is to improve the management of earthquake risk in the property industry by providing owners, tenants, users and the public a basic means to distinguish between buildings on the basis of assessed earthquake performance in terms of safety, damage and repair time.
QuakeStar is a private sector initiative funded by stakeholders in the property industry, building users and the general public.

The intention is to establish the QuakeStar rating system in the property market so that, for purchase or rental transactions, insurance and funding, questions are always asked about earthquake performance. The market will thus learn to put a value on the assessed earthquake performance of buildings. Strengthening of buildings will be rewarded by higher market valuation and the costs involved will be seen as an investment, not simply added cost. When the market rewards better earthquake performance, owners would not need to wait for a major earthquake to obtain benefit from their investment. Such an outcome would be fitting legacy of the Canterbury earthquakes. Owners, tenants and the public would be more aware of earthquake risks, be better able to manage them and more informed on the role of engineering in mitigating them.

The QuakeStar approach is to use the data on the fundamental aspects that influence earthquake performance. The ratings are intended as a guide for the property industry as a high-level means of distinguishing between buildings. Interested parties would still need to review detailed reports on earthquake aspects (as they would for other attributes such as finishes or energy efficiency). Having a rating to distinguish between buildings has the advantage of raising and sustaining awareness of earthquake risk and thus prompting owner and user response. However, there is a danger that the ratings are seen as a prediction of performance in a real earthquake and owners and users may thus be upset if actual performance does not match reality. The challenge is for the community to see the advantages of sustained awareness of earthquake risk while at the same time accepting that prediction of performance is well-nigh impossible.

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Over time, QuakeStar will result in improved public safety, improved resilience of buildings and cities and improved ability of owners and users to manage earthquake risk.

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Improve safety of users and public

• Market-driven retrofitting
• New designs to above minimum standards

Improve resilience of buildings and cities/towns

• Lower damage / Less disruption
• Quicker recovery / return to productivity

Improve awareness of owners/users/public

• Recognition that we live with earthquake risk
• Improved earthquake risk management
• Market value for good earthquake engineering

The proposed QuakeStar rating system aims to bring about changes in market approach to earthquake engineering and improve owner/user/public awareness of the value of earthquake engineering. In particular to:

• Promote higher standards of retrofit and new design
• Highlight the existence of low-rated buildings as a tolerable risk
• Promote discussion and consideration of community resilience – through the damage and repair time ratings
• Promote more informed and rational decisions on retrofit requirements and timeframes.
• Help the property market to put a value on earthquake performance

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The proposed operational structure and assessment process is shown below. For further details, refer to the Overview Presentation and Owner Guide.

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The QuakeStar approach achieves consistency by requiring an independent review of the assessments and ratings.

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• The owner appoints an Assessing Engineer (on a QuakeStar-approved list of individuals) who examines the site and the building and reviews the design documents, especially structural drawings.
• The Assessing Engineer uses QuakeStar Worksheets to assign the star-ratings for Safety, Damage and Repair Time.
• The owner appoints a Reviewing Engineer (approved as independent by QuakeStar) who reviews the assessment and the ratings of the Assessing Engineer.
• The Assessing Engineer and Reviewing Engineer must then compare notes and agree on each of the three ratings. (They do not have to agree on the detailed reasons).
• The owner receives the agreed ratings and reviews the reports from both the Assessing Engineer and the Reviewing Engineer. If it is clear that ratings would increase if identified improvements were made, the owner may choose to take action on these and ask the engineers to update their ratings.
• The owner then applies for ratification of the ratings by QuakeStar Office.
• Once ratified the basic ratings, but not the engineers’ reports, are available to all on the QuakeStar website.
• QuakeStar has an office, a website and a Governing Board. A Technical Advisory Panel reviews building ratings and approves Assessing and Reviewing Engineers.

For further details refer to the Overview Presentation and Owner Guide.

QuakeStar Rating	Risk of Harm*	Damage	Repair Time
★★★★★	Extremely low	Minimal	Days
★★★★	Very low	Moderate	Weeks
★★★	Low	Significant	Months
★★	Moderate	Substantial	> 6 months
★	High	Severe	> 1 year

• The ratings are based on assessment of the performance of the building in earthquake shaking matching that used in the design of new office buildings.
• Safety Rating reflects overall performance of the structure and building elements and their strength and integrity from a safety perspective.
• Damage Rating indicates damage that could occur in that level of shaking.
• Repair Time Rating indicates the time required to repair the building – assuming access to it and availability of reasonable resources. It does not account for lack of access to the building beyond the control of the owner.
• Taken together, these ratings give a valuable indication of the ability of the building to keep people safe, reduce damage and to restore operations after a major earthquake.
• The ratings are based on the assessments of experienced engineers and are intended as an overall guide to help owners, tenants, insurers and others differentiate between buildings at a “headline” level.
• They give a general indication of expected performance of the building, but due to the highly variable nature of ground shaking and building response in a real earthquake the ratings cannot be regarded in any way as being a prediction of performance in a particular event.

The QuakeStar system requires the owner to appoint an Assessing Engineer and a Reviewing Engineer, both of whom are acceptable to QuakeStar as individuals known and respected for their knowledge of building performance in earthquake, experience in a professional capacity in structural and earthquake engineering and the necessary judgement to assess likely outcomes.

Steps in the process are:

1. The owner appoints an Assessing Engineer (on a QuakeStar-approved list of individuals) who examines the site and the building and reviews the design documents, especially structural drawings.
2. The Assessing Engineer uses QuakeStar Worksheets to assign the star-ratings for Safety, Damage and Repair Time.
3. The owner appoints a Reviewing Engineer (approved as independent by QuakeStar) who reviews the assessment and the ratings of the Assessing Engineer.
4. The Assessing Engineer and Reviewing Engineer must then compare notes and agree on each of the three ratings. (They do not have to agree on the detailed reasons).
5. The owner receives the agreed ratings and reviews the reports from both the Assessing Engineer and the Reviewing Engineer. If it is clear that ratings would increase if identified improvements were made, the owner may choose to take action on these and ask the engineers to update their ratings.
6. The owner then applies for ratification of the ratings by QuakeStar Office. The owner pays a fee for this process. Reports by the Assessing and Reviewing Engineers may be required by QuakeStar on a confidential basis for the purposes of ratification only.
7. The QuakeStar Technical Advisory Panel reviews the building ratings and either confirms them or requests further work or clarification – until it is satisfied that the ratings are reasonable.
8. Once ratified the three QuakeStar ratings (Safety, Damage and Repair Time) are made available to all on the QuakeStar website.
9. Reports by the engineers remain confidential and may only be released to others with the written approval of the owners on each occasion.
10. The owner is obliged to advise QuakeStar of any significant changes to the building that may alter the ratings. In such a case the owner is required to obtain updated ratings from the original Assessing Engineer and Reviewing Engineer – or from different Assessing and Reviewing Engineers acceptable to QuakeStar.
11. Every five years the owner must submit an update report on the building and apply for extension of the rating and listing on the QuakeStar website for a further five years.

A: Role of QuakeStar Worksheets

QuakeStar Worksheets turn structural assessment data into a star rating.

QuakeStar Worksheets:

• Convert structural assessment data into star-ratings
• Have separate ratings for Safety, Damage, Repair Time
• Require minimal input to complete worksheets
• Focus on vital earthquake performance characteristics
• Require a detailed assessment of site and building
• Data is allowed from any credible source eg. (existing reports)
• Engineering judgement is needed to determine a score
• A score determines the star-rating according to the data entered
• Worksheets show the star-rating interactively as scores are entered

You can see Sample Worksheets here.

B: Engineer Rating Process

1. For overall process, refer Owner Guide or the Overview Presentation.
2. Assessing Engineer and Reviewing Engineer must be on list of individuals on QuakeStar list.
3. Applications to be on the QuakeStar list to be submitted with supporting information demonstrating suitable knowledge, experience and judgement.
4. For any particular building assessment, the Assessing Engineer and Reviewing Engineer combination must be acceptable to QuakeStar. This should be checked out before the QuakeStar assessment process begins.
5. A fundamental requirement of the QuakeStar process is that the Assessing Engineer and the Reviewing Engineer must agree on the star-ratings in each category. Agreement on the detailed reasons is not required, but details of any differences should be included in the engineer Reports.
6. QuakeStar Worksheets contain instructions on filling in assessment values. These are essentially %NBS values for the items concerned, but modified to account for buildings of higher importance:
   a. For IL2 buildings multiply %NBS values by 1.0
   b. For IL3 buildings multiply %NBS values by 1.3
   c. For IL4 buildings multiply %NBS values by 1.8
   In other words, the QuakeStar scores are based on 500-year shaking
7. Refer the Overview Presentation for more details on the QuakeStar Worksheets.
8. Minimal input is required to complete the Worksheets. The amount of work needed to determine suitable values is up to the Assessing and Reviewing Engineers and will vary according to the scale and complexity of the building.
9. Detailed assessment needed of site and building is needed
10. Data is allowed from any credible source, including existing reports
11. Engineering judgement is needed to determine values to be entered.
12. Score determines star-rating according to data entered
13. Worksheets show star-rating interactively – as scores are entered. This allows users to review the sensitivity of the star-ratings to change in any particular value entered.
14. The Assessing Engineer’s Report must show each Worksheet with all values entered. This should be accompanied by a written report highlighting key assumptions, methods used, and any important issues. For example, the report should highlight that one particular feature is reducing what would otherwise be a higher rating. (This should be apparent from the Worksheet Output.)
15. The table below shows the QuakeStar Safety Scores and corresponding Star Ratings.

Building Importance Level (IL)	Typical example	Seismic Factor for New Building Standard	%NBS for building to New Building Standard	QuakeStar Safety Score	QuakeStar Safety Rating
IL2	Office Building	1.0	100%NBS	100 - 130	★★★
IL3	School	1.3	100%NBS	130 - 170	★★★★
IL4	Hospital	1.8	100%NBS	180 - 230	★★★★★

Safety Worksheet – interactive Excel spreadsheet

Engineers enter figures in the “User input” columns based on their assessments. These figures are essentially the %NBS figures for each, adjusted for building importance.

The Worksheet examines those figures and assigns a Overall Safety Rating based on the lowest values in each section and then overall.

The Safety Worksheet provides a one-page overview of the building from which it is easy to identify critical items that are reducing the rating.

Damage and Repair Time Worksheet 2A – interactive Excel spreadsheet Vulnerability Method

Engineers enter values in the User Input columns for Damage and Repair Time.

Damage Worksheet

This is one of two methods, the Vulnerability Method and the Damage Ratio Method (see next slide). In this Vulnerability Method the engineer is required only to rate each element as High, Moderate or Low vulnerability to the effects of 500-year shaking on the building. Pre-assigned values are used to compute the estimate damage. Users may alter the pre-assigned values if they wish.

The Worksheet computes an estimate of overall damage based on entered values and assigns the Damage Rating accordingly.

Repair Time Worksheet

Engineers are required to assess the time from start of design work through to completion of the stated item. They then enter a code (1-5 in red) to match the assessed time – which then appears in the Repair Time column. The Worksheet then looks for the longest time and assigns the star rating based on that.

The effect of External Services supplying the building is included and the ratings made with and without considering these.

Damage and Repair Time Worksheet 2B - interactive Excel spreadsheet

Damage Ratio Method

Assessors enter values in the User Input columns for Damage and Repair Time. The Worksheet assigns star ratings based on the figures entered.

Damage Worksheet

This is one of two methods, the Vulnerability Method and the Damage Ratio Method (see next slide). In this Damage Ratio Method the engineer enters damage ratio assessments for each item based on the effects of 500-year shaking on the building.

Any recognised source of damage estimates may be used, for example HAZUS. The Worksheet computes an estimate of overall damage based on entered values and assigns the Damage Rating accordingly.

Repair Time Worksheet

Engineers are required to assess the time from start of design work through to completion of the stated item. They then enter a code (1-5 in red) to match the assessed time – which then appears in the Repair Time column. The Worksheet then looks for the longest time and assigns the star rating based on that.

The effect of External Services supplying the building is included and the ratings made with and without considering these.

External Factor Worksheet – interactive Excel spreadsheet

Factors beyond the subject site can influence the earthquake performance of a building. For example, a vulnerable building next door may collapse on to the subject building. It is difficult and not practicable to assess the likely effects of the External Factors on the rating of the subject building. The External Factor sheet allows engineers to record the existence or not of the listed external factors and to make notes for information of interested parties.

However the External Factor sheet asks engineers to broadly assess the reduction in rating, for each of Safety, Damage and Repair Time, that would result from the worst External Factor effect. They indicate this at the top right of the sheet.

The ratings for Safety, Damage and Repair Time remain unchanged but where there is an External Factor effect, the reduction in rating is indicated by displaying the stars as hollow rather than solid.

For example, if a reduction of two stars was identified for External Factors:

A three star rating: ★★★

Would be shown as: ★☆☆

Safety Worksheet 1-R – interactive Excel Worksheet

The QuakeStar Residential Worksheets are used in a similar way to the corresponding Commercial Worksheets.

They are designed to apply to small residential buildings such as houses and low-rise apartment blocks.

Values entered on this Safety Worksheet are the %NBS values for each item adjusted for building importance if the building is used for IL3 or IL4 purposes.

Values for each direction are required. The spreadsheet examines the values entered and determines the rating based on the lowest value in each category and then overall.

Damage and Repair Time Worksheet 2A-R – interactive Excel Worksheet

Vulnerability Method

Assessors enter values in the User Input columns for Damage and Repair Time. The Worksheet assigns star ratings based on the figures entered.

Damage Worksheet

This is one of two methods, the Vulnerability Method and the Damage Ratio Method (see next slide). In this Vulnerability Method the engineer is required only to rate each element as High, Moderate or Low vulnerability to the effects of 500-year shaking on the building. Pre-assigned values are used to compute the estimate damage. Users may alter the pre-assigned values if they wish.

The Worksheet computes an estimate of overall damage based on entered values and assigns the Damage Rating accordingly.

Repair Time Worksheet

Engineers are required to assess the time from start of design work through to completion of the stated item. They then enter a code (1-5 in red) to match the assessed time – which then appears in the Repair Time column. The Worksheet then looks for the longest time and assigns the star rating based on that.

The effect of External Services supplying the building is included and the ratings made with and without considering these.

Damage and Repair Time Worksheet 2B-R – interactive Excel Worksheet

Damage Ratio Method

Assessors enter values in the User Input columns for Damage and Repair Time. The Worksheet assigns star ratings based on the figures entered.

Damage Worksheet

This is one of two methods, the Vulnerability Method and the Damage Ratio Method (see next slide). In this Damage Ratio Method the engineer enters damage ratio assessments for each item based on the effects of 500-year shaking on the building.

The Worksheet computes an estimate of overall damage based on entered values and assigns the Damage Rating accordingly.

Repair Time Worksheet

Engineers are required to assess the time from start of design work through to completion of the stated item. They then enter a code (1-5 in red) to match the assessed time – which then appears in the Repair Time column. The Worksheet then looks for the longest time and assigns the star rating based on that.

The effect of External Services supplying the building is included and the ratings made with and without considering these.

External Factor Worksheet 3R – interactive Excel spreadsheet

Factors beyond the subject site can influence the earthquake performance of a building. For example, a vulnerable building next door may collapse on to the subject building. It is difficult and not practicable to assess the likely effects of the External Factors on the rating of the subject building. The External Factor Worksheet allows engineers to record the existence or not of the listed external factors and to make notes for information of interested parties.

However the External Factor sheet asks engineers to broadly assess the reduction in rating, for each of Safety, Damage and Repair Time, that would result from the worst External Factor effect. They indicate this at the top right of the sheet.

The ratings for Safety, Damage and Repair Time remain unchanged but where there is an External Factor effect, the reduction in rating is indicated by displaying the stars as hollow rather than solid.

For example, if a reduction of two stars was identified for External Factors:

A three star rating: ★★★

Would be shown as: ★☆☆

 

Some indicative QuakeStar examples

REAL BUILDINGS - Based on existing reports and only partial information
QuakeStar Preliminary Assessments Summary - Office Buildings

Design	%NBS	QuakeStar Score	Safety	Damage	Repair	External Factors	Comment
1950s	60	62	★	★★	★	3	Robust MWD design but dated
1987	100	121	★★★	★★★	★★	4	Stair details not checked
1988	100	133	★★★	★★★	★★	4	Assumes no issues with floor support
Late 70s	75	100	★★	★★	★	5	Limited by façade detailing (**** otherwise)
1996	65	71	★★	★★	★	4	Damage issues with floors and reclaimed site
1973	90	88	★★	★★	★★	5	Issues with separation, stairs
1973/2004	80	97	★★	★★	★	3	Close to *** on Safety
1986	65	54	★	★★	★	2	Separation, column capacities
1986	90	73	★	★★	★	2	Stair issues. Otherwise **
1979/2004	100	100	★★	★	★	4	Safety *** with no issues on stairs / floors
2009	100	107	★★★	★★	★	6
2002	133	161	★★★	★★★★	★★	4	133%NBS means low impact at 500yr shaking
1989	120	145	★★★	★★★	★★	4
1986	110	96	★★	★★	★★	3	Issues with diaphragms / blockwall separation
Late 70s	110	80	★★	★★	★	3	Issues with floor supports and column detailing
70s /2007	100	110	★★★	★★★	★★	3

This table shows some indicative ratings based on existing assessments of some existing multi-storey buildings in Wellington and Auckland.  Not every aspect has been assessed to meet QuakeStar requirements but the table gives an indication of how buildings of different types and ages could rate.

Some indicative QuakeStar examples

IMAGINARY BUILDINGS - Including possible new designs
QuakeStar Preliminary Assessments Summary

Design	%NBS	QuakeStar Score	Safety	Damage	Repair	Comment
1930	40	30		★	★	URM with 40%NBS
1930	50	40	★	★	★	URM with 50%NBS
1960	50	45	★	★	★	Pre 1965 Reinforced Concrete with 50%NBS
2015	100	130	★★★	★★	★	New IL2 Design - conventional
2015	100	130	★★★	★★★★	★★	New IL2 Design - with Base Isolation
2015	100	170	★★★★	★★★	★★	New IL3 Design - conventional
2015	100	170	★★★★	★★★★★	★★★	New IL3 Design - with Base Isolation
2015	100	230	★★★★★	★★★	★★★	New IL4 Design - conventional
2015	100	230	★★★★★	★★★★★	★★★★	New IL4 Design - with Base Isolation

This table shows some hypothetical examples to illustrate the full range of ratings – from a low-rated old brick building (URM40) to a modern building designed to IL4 requirements with the additional benefit of base-isolation which rates 5-star for Safety, Damage and Repair Time.

There are no official QuakeStar rated buildings at present. This is where ratings of buildings will appear as each rating is made and ratified.

Resilient Buildings for New Zealand – Who Cares?

A Call for Action

Leaders of our communities say they want resilient buildings and resilient cities that can bounce back from major earthquakes. Engineers can deliver resilient buildings, but only if other stakeholders want them and can see their value.

Combined action by stakeholder groups can do much to develop attitudes and approaches across the industry that will reduce the impact of future earthquakes on New Zealand communities.

Key stakeholders are; Central government, local government, property owners, developers, bankers, insurers, architects, earthquake engineers, tenants and building users.

The QuakeStar concept (www.quakestar.org.nz), seeded into the marketplace, can be used to help all stakeholders to understand what a resilient building is and to help them to view low damage and short repair times as desirable features in New Zealand buildings.

Who will step up and lead such a move towards greater earthquake resilience for New Zealand buildings?  Central government?  Insurers?  Local Government New Zealand?

A property market that values buildings that are resilient in an earthquake would be a fitting legacy from the devastating effects of the Canterbury Earthquakes.

Click here for full presentation

David Hopkins

BE(Hons) PhD CPEng FENZ Life Member NZSEE

Consulting engineer and QuakeStar proponent.

Auckland  May 2019

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Financial support – acknowledgement

QuakeStar acknowledges with thanks the financial support of the NZ Earthquake Commission (EQC) to assist with development of the Worksheets for Commercial and Residential buildings and in particular the support of Richard Smith, Manager Education and Research.

Stakeholder Liaison

QuakeStar acknowledges the recent discussions and feedback from the following:

• Property Council of New Zealand – Connal Townsend
• Insurance Council of New Zealand – Tim Grafton, John Lucas
• Local Government New Zealand – Malcolm Alexander, Frances Sullivan
• Infrastructure Council of New Zealand – Stephen Selwood
• Institution of Professional Engineers (IPENZ) – Susan Freeeman-Greene
• NZ Society for Earthquake Engineering – Peter Smith
• Structural Engineering Society of NZ – Paul Campbell
• Wellington City Council – Justin Lester, Anthony Wilson, Steve Cody, Mike Mendonca
• Christchurch City Council –  Lianne Dalziel, Mike Galoolly.
• NZ Bankers Association – Karen Scott-Howman, Anthony Buick-Constable
• MBIE – Hon Dr Nick Smith, Mike Stannard
• NZ Green Building Council – Andrew Eagles, Alex Cutler
• The Wellington Company – Ian Cassels
• Chris Gudgeon – Kiwi Property

Establishment Advisory Group

Dr David Hopkins (DHCL), Bob Burnett (BB Architecture), Don Holden (InLaw Group), Ron Mayes (US Resiliency Council).

Technical Review Group (Worksheet Development)

John Hare, Geoff Sharp, Hamish McKenzie (Holmes Consulting), Rob Jury, Kam Weng Yuen (Beca), Will Parker (Opus), Derek Bradley, Barry Davidson, Anthony McBride, Tony Stuart, Nic Brooke (Compusoft), Peter Smith, Jon Devine (Spencer Holmes), Craig Stevenson (Aurecon), Mike Stannard, David McGuigan, Graeme Lawrance, Darrel Cheong (MBIE), Stefano Pampanin (University of Canterbury), Brendon Bradley (University of Canterbury and QuakeCore), Ken Elwood (University of Auckland and QuakeCore)

Support QuakeStar

Once QuakeStar Incorporated is established a section of this site will enable organisations and individuals to support QuakeStar by becoming members or recognised sponsors.

• Jesse Mulligan Ron Mayes Interview 16 Nov 2016: http://www.radionz.co.nz/national/programmes/afternoons/audio/201824109/to-rebuild-or-demolish
• Kathryn Ryan David Hopkins interview 17 Nov 2016: http://www.radionz.co.nz/news/national/318282/introduce-quake-star-ratings-for-buildings-engineer
• Catherine Harris Sunday news piece 19 Nov 2016 http://i.stuff.co.nz/business/property/86510220/What-a-quake-teaches-us-about-buildings
• Catherine Harris piece re QuakeStar 13 Sep 2015: http://i.stuff.co.nz/business/71925388/Engineering-expert-looks-for-support-for-Quake-Star-a-new-seismic-rating-system-for-buildings

• David Hopkins paper to NZSEE Conference 2016 on QuakeStar: http://www.nzsee.org.nz/db/2016/Papers/O-24%20Hopkins.pdf
• David Hopkins SESOC 2012 paper Engineering Matters: http://www.sesoc.org.nz/Journals/newsletters/SESOC_Issue_13_-_Dec_2012.pdf
• Will Parker, et al paper SESOC Conference 2012:
  https://quakestar.org.nz/wp-content/uploads/2017/04/QuakeStar_paper_draft_18_sep.pdf
• Mayes, Wetzel et al Paper NZSEE Bulletin Vol 46 No1 March 2013: http://www.nzsee.org.nz/db/Bulletin/Archive/46(1)0040.pdf