Shakin' all over?

Ten months ago, provincial civil servants advised the government there was a "limited understanding" of how wood-frame buildings taller than four-storeys would react in an earthquake. But, despite that continuing lack of knowledge, the government went ahead and allowed their construction anyway.

That advice was first included in a June 20, 2008 briefing note prepared for Housing and Social Development Minister Rich Coleman.

A month later, another briefing note for the minister echoed that advice, adding "although some jurisdictions in the US have implemented changes" to permit such buildings "they have not reviewed seismic issues."

As a result of that limited understanding, the Campbell administration has partnered with the American National Science Foundation's Network for Earthquake Engineering Simulation program to test a six-storey wood-frame building on the world's largest seismic simulation shake table.

According to a February news release distributed by one of the project's corporate collaborators, that test is scheduled to take place in June and July.

In an interview with Public Eye, project team member Andre Filiatrault - the director of the University of Buffalo's structural engineering and earthquake simulation laboratory - said qualitative results would be available almost immediately.

Although the reports interpreting those results won't be written up until the fall.

But, as of April 6, such buildings can now be constructed in British Columbia thanks to a building code amendment introduced by the government on January 8.

Under that amendment, the government is requiring taller wood-frames to meet certain requirements it says will make them resistant to seismic forces.

According to a ministry spokesperson, if the results of the shake table test "indicate the need for building code requirements to be refined, the Province will begin that process."

But what happens to those buildings that have already begun construction before those results are available?

"Codes do not retroactively apply to existing buildings," the spokesperson replied. "Buildings must comply with the code in effect at the time they are constructed."

In an interview on January 26, University of British Columbia earthquake engineer facility director Carlos Ventura expressed doubts about the government's seismic mitigation measures as they were first written.

"We don't have evidence to state these are conservative provisions" as the government has claimed, said Dr. Ventura. "Is that sufficient? Maybe it is? Maybe it is not? But we just don't have the hard data to show that works."

On April 7, the government quietly announced additional building code changes had been made on April 3 to "strengthen" those measures as a result of "continuing research and analysis."

The following is an edited copy of the aforementioned briefing notes.

***

MINISTRY OF HOUSING AND SOCIAL DEVELOPMENT
BRIEFING NOTE

CLIFF# 94097
Date: July 10, 2008

PREPARED FOR: Minister Coleman - For Information

ISSUE: Scheduled Process for Implementation - BC Building Code Changes to Permit Six-Storey Wood-Framed Construction

BACKGROUND:

* The BC Building Code restricts wood framed construction to four storeys
* Canadian Wood Council (CWC) has begun discussions at the national level for changes to the model National Building Code
* Although some jurisdictions in the US have implemented changes, they have not reviewed seismic issues
* To facilitate making changes to the BCBC to allow six-storey wood-framed construction, the BPSB worked with the Office of the Chief Information Officer to complete a scoping review. Highlights include:

* Seismic, structural, fire safety and sound transmission considerations;
* Advantages of wood frame construction, such as low energy use and less carbon emissions;
* Review of fire and buildings codes in other jurisdictions permitting six storey wood frame construction.

DISCUSSION:

To implement the changes to the BC Building Code, BSPB is:

* "Importing" regulations from other jurisdictions e.g., US cities
* Meshing and integrating the best regulations into the BC Building Code
* Ensuring the building regulatory and inspection process and community fire fighting capabilities are sufficient for successful implementation
* Developing a pilot project with the Canadian Wood Council

Three parallel "streams" of activity are underway:

1. Technical development
2. Working with industry
3. Announcements

Technical Development

* Posted Request for Proposal: RFP posting on BC Bid to solicit proposals from fire protection engineers and code change experts to ensure code changes result in safe and successful six-storey wood buildings in the BC context.

* Initiated seismic research partnership: with the University of Buffalo on six storey wood frame structure testing on the world's largest seismic simulation shake table in Miki City, Japan in spring 2009.

* Identified technical and policy areas requiring work:

* Wood shrinkage
* Seismic risks
* Fire safety
* Costs

Working with industry

* Website

* Updated bi-weekly; code users are kept up to date and can provide feedback

* Industry Advisory Committee on Wood Construction

* To capitalize on best industry expertise by including such stakeholders as Canadian Wood Council, Forintek, warranty providers, Architectural Institute of BC, Assoc. of Professional Engineers and Geoscientists, Fire Chiefs Association, etc.
* Working with Minister-appointed Building Policy Advisory Committee (BPAC) to test ideasl they support this initiative while also supporting code user involvement in development stage. (see Appendix B)

* Code User Sessions

* To create public awareness, introduce concepts and get feedback throughout the process.

Announcements

August 2008

* Website launch
* Multi-storey wood issue with ongoing updates of progress and proposals

* Industry advisory committee created
* Minister "kick off" event for first meeting
* Industry experts on wood construction involved

September 2008

* UBCM announcement of pilot and draft code provisions
* CWC interest in pilot project (HEF funding);
* Invitation to build the first six-storey wood-framed buildings as a pilot project; partnership with industry
* Introduce draft code provision and industry education

October/November 2008

* Industry feedback session
* Minister introduces session
* Industry provides final feedback and input on code changes for six-storey wood-framed construction

December 2008

* Minister announcement of results
* Finalized technical content and implementation date

Opportunities and Challenges/Risks

Appendix A outlines the following opportunities and risks to allowing combustible construction in buildings restricted by BCBC to non-combustible construction:

Opportunities
* "The Best in Canada"
* Economic
* Sustainability
* Innovation and Quality

Challenges/Risks:
* Fire and life safety risks
* Structural shrinkage and moisture management challenges
* Seismic risks
* Building Code development cycle
* Education and training challenges

Author: Carrie Daniels, Senior Policy Analyst, BSPB
Contact: Trudy Rotgans, Manager, BSPB
Date: July 9, 2009
Attachment(s): Appendix A and B; Visual Timelines

***

Appendix A - Opportunities and Challenges/Risks

Opportunities:
* "The Best in Canada"
* The province's investigation to increase the storey limit on wood frame construction in the Code makes BC a leader in this type of construction in Canada.

* Economic
* With world steel costs continuing to risk, wood is an affordable construction material that is becoming increasingly attractive to builders;
* expanding the application wood could increase the affordability of housing with the expansion of density to six storeys;
* British Columbia is well positioned to supply wood products as demand increases, a likely bi-product of enhancing the storey construction limits in the BC Building Code from four to six storeys.

* Sustainability
* Wood framed houses have low energy usage, compared to concrete built structures;
* Wood is easy to insulate to high standards;
* Less carbon is emitted when constructing wood framed buildings.

* Innovation and Quality
* In mitigating the risks associated with six storey wood framed construction, new and innovative building practices may be required as part of the Code requirements;
* Six storey wood frame construction may require more detailed construction practices and as a bi-product create a higher quality of building practices for this type of construction.

Challenges/Risks:
* Fire and life safety risks
* There is technical difficulty in achieving a true two hour fire separation with a wood floor; this risk increases with multi-storey wood framed construction.
* It may be prudent to introduce some allowance for combustible materials within non-combustible construction types as well, rather than an all or nothing solution in order to mitigate fire risks.
* There is an enhanced fire risk during construction with wood and wood products; strategies to address construction risk need to be considered.

Challenges/Risks continued:

* Structural shrinkage and moisture management challenges
* The risk of wood shrinkage in BC is different than the conditions seen in California or elsewhere; there is significantly more rain/moisture conditions to consider, which may lead to overall building damage.
* Shrinkage can be a serious concern when wood is set against concrete components of a building, such as an elevator shaft or balconies; there can be up to 5 inches of shrinkage, possibly more.
* Wood shrinkage is manageable with proper awareness and education; building higher levels of wood-framed construction may not be an issue if the proper safe guards and education/training are in place.

* Seismic risks
* There is a limited understanding about performance of wood framed building types over four storeys
* BSPB has contacted the University of Buffalo which is sponsoring a six storey wood frame structure test on the world's largest seismic simulation shake table in Miki City, Japan in the spring of 2009.

* Building Code development cycle
* The National Building Code and the BC Building Code are consensus based documents that emerge from thorough examination of health and safety risks through various tests of rigour including consulation with industry, affected stakeholders and subject matter experts.
* Code changes made without thorough regard to consequences can lead to liability challenges for the industry and local governments.

* Education and training challenges
* It takes time for industry to become proficient in new Building Code requirements and techniques.
* Any Code change requires lead-in time for the training and education of industry as well as building officials who are asked to enforce new Building Code provisions.

***

Appendix B - Building Policy Advisory Committee

* The Building Policy Advisory Committee (BPAC) has the following comments:

* Overall very supportive - would like to see this increase.
* Cautious about timing - indicating that industry requires lead time for training and education related to - indicating that industry requires lead time for training and education related to any Building Code changes
* Strongly support an opportunity for public input, similar to all Code change proposals
* Suggest that significant technical and policy work needs to be done on the issues of:

* Wood shrinkage
* Seismic risks
* Fire safety
* Costs

* BCPAC membership includes representatives from:

* Canadian Home Builders Association - BC
* Architectural Institute of BC
* Association of Professional Engineers and Geoscientists
* Urban Development Institute
* Applied Science Technologists and Technicians
* BC Construction Association
* Building Officials Association of BC
* Union of BC Municipalities
* Independent Contractors and Businesses of BC
* City of Vancouver
* Homeowner Protection Office

* Additional correspondence from impacted industry and other impacted stakeholders is currently being received by the Ministry. The pulse of industry based on incoming correspondence to be monitored.

***

2008-2009 ESTIMATES DEBATE

OFFICE OF HOUSING AND CONSTRUCTION STANDARDS

ISSUE: Six-Storey Wood Frame Construction

QUESTION: What is the provincial government doing to allow six-storey wood frame construction in British Columbia?

KEY POINTS:

* With B.C.'s booming construction sector, there is a strong interest in encouraging the use of B.C. wood products in our buildings.

* Wood construction can be less expensive and have less impact on the environment than the concrete and steel used now. Using more wood may expand market opportunities for the forest sector.

* The aim of the Building Code is life safety for the for occupants of all buildings.

* Technical solutions will balance the economic and environmental benefits of wood construction with any safety concerns.

BACKGROUND:

* The purpose of the BC Building Code is to establish consistent, minimum standards for new construction and building alteration.

* Policy work is underway to examine opportunities and mitigation strategies for risks in permitting construction of six-storey wood frame buildings.

* A scoping review on multi-level wood framed structures has been completed by the Office of the Chief Information Officer; the review contains information on what other jurisdictions are doing with regards to this construction standard.

* Opportunities for six-storey wood frame construction include:

* Economic benefits
* Sustainability benefits
* Innovation in building practices in BC

* Mitigation strategies are required to manage:

* Life and safety risks
* Seismic risks - limited understanding about performance of this building type
* Structural shrinkage risks - which lead to building damage
* Moisture management risks

Title: Six Storey Wood Frame Construction
Contact: Jeff Vasey, Executive Director
Prepared by: Carrie Daniels
Date: June 20, 2008

2 Comments

Great, another batch of leaky condos coming up
hg

Very interesting briefing notes you dug up there Mr. Holman.

If I remember correctly, did not the Minister himself, Mr. Coleman, tell you that there were no concerns raised in any of his briefing notes?

And did you not record that conversation for, how shall we put it, posterity?

____
All joking (and anti-parsing?) aside, perhaps an interesting follow-up question to put to the Minister (if you ever get the chance), would be:

"Do the locations in Europe that you, Mr. Coleman, stated are 'going to nine' stories, sit on major geological fault lines in the way that most of the major urban centers in coastal British Columbia do?"

Thanks.


.

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