Technical Bulletins

• Engineering Modifications to Fire Tested and Listed Assemblies
• Members Reminded to Use Stamps or Seals
• Assessment of Seismic Slope Stability
• 2006 BC Building Code Now Available
• Addressing Smoke and CO Control in Elevator Machine Rooms
• Non-Endorsed Letters of Assurance

Archive of Past Technical Bulletins

Engineering Modifications to Fire Tested and Listed Assemblies - Innovation January/February 2007

For both new and existing construction, the BC Building Code mandates that some structural elements such as exterior walls, load bearing walls, columns, beams, floor/ceiling assemblies and roofs achieve a minimum fire resistance rating. Similarly, fire-rated separations or assemblies are also required between different uses and occupancies. When a fire-rated assembly is penetrated by closures, doors, piping, wires, conduits, ducting or other elements, it requires adequate protection systems to maintain the level of fire separation of the assembly. Typically, building designers either specify a design listed by a testing/certification agency or use generic designs or assemblies outlined in the Building Code.

Fire-rated assemblies are tested in accordance with a standard fire test and assigned an hourly fire resistance rating based on time to failure. In Canada, this standard is CAN/ULC-S101-04, Standard Methods of Fire Endurance Tests of Building Construction and Materials . Similar standards, such as ASTM E119 and UL 263, are used in the US to establish a fire resistance rating for various building materials.

In Canada, these tests must be carried out by independent testing/certification agencies accredited by the Standards Council of Canada. These agencies play an important role in the certification and quality control of tested products. These certifications are then listed in their directories and these listings may be used by architects, engineers, designers, authorities or contractors in designing and assessing the fire resistance rating of various assemblies and systems.

• Over the years, questions have been raised regarding modifications to listed assemblies – that is, when a manufacturer, supplier, designer, contractor or installer makes changes to the assembly that were not included and/or contemplated as part of the original testing/listing of that product. The ULC list of equipment and materials includes some supplementary information to assist the users in deviations from the listed assemblies; these acceptable deviations are listed under heading “Consideration of Variations from Tested Designs” and provide guidance with respect to limits to these variations and/or transfer of components from one design to another before these changes impact the performance of the assembly. Any modification to a listed assembly or system beyond that envisioned under the applicable standard should be assessed to ensure the level of performance expected by the listing.

From a practical point of view, listed assemblies are often modified either during the design or construction stages of building projects. As the manufacturers of various assemblies/systems have a vested interest in the use of their products and generally have an in-depth knowledge of them, they are often asked to evaluate and provide suggestions for modifying their listed systems to suit specific construction conditions. However, it is not feasible for manufacturers to test every variation of a product. In order to assist engineers and architects in such matters, the performance of modifications to listed assemblies may be formally commented upon by manufacturers based on the test results from similar tested assemblies/systems and often without the consent of the listing agency that originally certified the product.

For instance, in the case of the firestop industry, some firestop manufacturers have been issuing commentaries on modifications to listed assemblies in the form of “Engineering Judgements.” “Engineering Judgements” are often presented in such a manner that they can cause confusion as the document may refer to an expectation that the modified assembly will pass a ratings test. Many engineers, architects, designers, authorities, and contractors have traditionally accepted these “Engineering Judgements,” assuming that they either have current listing, or that they have been reviewed and someone is taking responsibility for this modification.

The fact is that these manufacturer supplied “Engineering Judgements” need to included an engineer’s seal. Otherwise engineers and/or architects may unknowingly take responsibility for these modifications under their Letters of Assurance. This concern was brought to the attention of the APEGBC Building Codes Committee and in July 2006 the Committee issued a letter to several firestop manufactures indicating that all “Engineering Judgments” should carry confirmation of engineering review.

Technical documents dealing with modifications to listed assemblies or the development of new assemblies not specifically listed relating to fire protection applications in buildings involves the practice of professional engineering as defined in the Engineers and Geoscientists Act of British Columbia. On this basis, these documents must be sealed by a professional engineer registered or licensed in BC who shall take responsibility for the design under seal.

In summary, if any modification is made to a listed assembly to address conditions outside a listing, or to address changes in materials or methods of installation to a listed assembly, these designs require confirmation of engineering review and all deviations to a listed assembly must be clearly identified as such. Confirmation of engineering review is provided by the engineer placing his professional seal on the document. This professional engineer must be registered or licensed in BC. The noted exception being where confirmation of the acceptability of the modifications is provided by the appropriate listing agency accredited by the Standards Council of Canada.

Members Reminded to Use Stamps or Seals - Innovation January/February 2007

In the next few years, British Columbia will see many new, capital-intensive developments such as ports, bridges, pipelines, and mines. As APEGBC members are aware, these developments go through environmental review before the provincial and federal governments will issue approvals and permits. However, what members may not know is that the provincial government routinely reviews application documents that are not stamped by professional engineers or professional geoscientists.

The BC Environmental Assessment Office (EAO) reviews complex multi-volume applications for large developments. These contain technical information that clearly falls within the practice of professional engineering or professional geoscience. In some recent applications filed with the EAO, the technical information has not been signed or stamped by the authors.

Following correspondence between APEGBC’s Environment Committee and the EAO, Association representatives met with the EAO to discuss the issue. At this meeting, APEGBC pointed out that no one is permitted to practice engineering or geoscience in BC unless they are licensed by the Association and noted that Section 20 (9) of the Engineers and Geoscientists Act explicitly requires members to seal or stamp work that they have undertaken in a professional capacity. APEGBC recommended that EAO consider any application as incomplete unless its authors are properly identified. The EAO representatives declined to assist, stating they could not be placed in a role of enforcing the Engineers and Geoscientists Act.

The Association is considering its next steps on this important issue. In the meantime, members who are responsible for producing estimates, specifications, designs or interpretations that are intended for review by government agencies and the public are reminded to ensure that their work is stamped or sealed. This also applies to multi-discipline reports, which can include a table that identifies the portion of the report that the author is responsible for, and which contains the seals or stamps of the members involved.

Assessment of Seismic Slope Stability - Innovation January/February 2007

On December 13, 2006, the provincial government enacted building regulation M268. The building regulation reads as follows:

“Where the intended use of the land is the construction of a building, the geotechnical study and geohazard assessment for slope stability of that land must be based on ground motion values having a 10% probability of exceedance in 50 years.”

Here, “building” has the same meaning as in the BC Building Code.

As referenced in the Commentary on Geotechnical Slope Stability (Seismic) Regulation, dated January 2, 2007, this regulation is made pursuant to Section 692(d) of the Local Government Act. Using this enabling legislation restricts the application of the regulation to only those slopes that could impact the structural safety of a building.

Materials are being developed to guide local governments and industry. The Building Policy Branch of the Office of Housing and Construction Standards has entered into discussions with APEGBC to establish practice guidelines for seismic slope stability assessments on a building that consider the influence of ground acceleration due to an earthquake. The provincial government has also extended an invitation to the Union of BC Municipalities to work with the provincial government on establishing an acceptable level of risk that a community is willing to accept.

This information was conveyed by the Building Policy Branch in Bulletin No. B06-06, dated December 14, 2006, and a subsequent commentary issued on January 2, 2007.

More information is available on the Building Policy Branch website at www.housing.gov.bc.ca/building/regs/seismic.htm.

2006 BC Building Code Now Available - Innovation November/December 2006

The 2006 BC Building Code and BC Fire Code are now available to the public. The BC Building Code includes Part 7 - BC Plumbing Services

As noted by the BC Building Policy Branch, the new 2006 Code requirements will apply to all buildings constructed on or after December 15, 2006, except those buildings for which a permit application has been accepted prior to December 15, 2006.

The new BC Building Code and Fire Code are based on the 2005 National Building Code of Canada and the 2005 National Fire Code of Canada, and establish minimum standards for health, safety, accessibility, fire and structural protection of buildings in BC, and protection of buildings from water and sewer damage. The 2006 edition of the codes use a new objective-based format. The objectives describe the overall goals that the Codes’ provisions are intended to achieve, and all requirements in the Codes are linked to one or more main objectives.

Volunteers from the engineering, architectural, fire, plumbing and building officials’ associations have been working with the BC Building Policy Branch to develop comprehensive code education for building industry professions in BC. Code Change Seminar material is being developed for delivery by code practitioners and consulting specialists who have undertaken a line-by-line review and comparative analysis of the existing BC Codes, the proposed 2006 BC Codes and the 2005 National Codes. 

An introduction to the structure and changes in the 2006 BC building, plumbing and fire codes and the City of Vancouver Building Bylaw will be highlighted at the annual Education Workshop of the Building Officials’ Association of BC (BOABC) to be held November 23 - 25, 2006 in Richmond, BC. The Plumbing Officials’ Association will also be having a discussion on the highlights of the new BC Plumbing Code at their annual Education Conference in Richmond on October 21.

Code Change Seminars are being planned for delivery within jurisdictions across British Columbia in early 2007, when it is expected that code users will have had the opportunity to better familiarize themselves with the new code structure and content. These seminars will be offered in two-day sessions for a registration fee expected to be in the range of $200 for two days. All registrants will receive a detailed guide covering the changes in the 2006 BC Codes.  This guide will include a table outlining all changes, as well as diagrams and explanations for the substantive changes.

The details, locations, schedules and times for the provincial delivery of the two-day Code Change Seminars, set for early 2007, are being planned and will be announced at the November BOABC Education Conference.

To register for BOABC’s annual Education Workshops to be held November 23 to 25 or for additional information on the Code Change Seminars, please contact the Steering Committee Chairman George.Humphrey@burnaby.ca or the BOABC Executive Director Richard Bushey at richbushey@shaw.ca.

For information on ordering the 2006 BC Building Code and Fire Code, visit the Government Publication Services Building Codes website at www.bccodes.ca or contact them toll free at 1-800-663-6105.

Addressing Smoke and CO Control in Elevator Machine Rooms - Innovation May/June 2006

In recent years, new technology in multistorey building construction has allowed the elevator machine room, which formerly was commonly located at the top of the building, to be moved into the basement, with the remainder of the basement used for a parking garage. In certain instances this has raised concerns over smoke migration and control in highrise buildings and carbon monoxide control in all buildings.

This issue, which is not clearly addressed in the current BC Building Code, was brought to the attention of the APEGBC Building Codes Committee. This Technical Bulletin is issued for general information and is not to be relied upon as a solution to this issue; the possible solutions need to be evaluated on a project-by-project basis.

The Problem

On recent projects, ventilation openings between the elevator machine room and the parking garage have been provided without taking into account the existence of openings between the elevator machine room and the elevator shaft. Openings between the elevator machine room and the elevator shaft are permitted by Part 3 (Sentence 3.5.3.3.(2)) of the BC Building Code.

Designers are also meeting the Building Code requirement for a fire separation between the elevator machine room and the adjacent floor area by providing a fire damper at the ventilation openings between the parking garage and elevator machine room.

However, since fire dampers are heat activated and do not activate by smoke or carbon monoxide, there is the possibility of smoke and carbon monoxide migration from the parking garage through the elevator machine room and into the elevator shaft.

What the Code Currently Requires

For highrises (as defined under the Building Code), Part 3 (Sentence 3.2.6.2.(2)) of the Code requires measures to limit smoke movement from a fire in a floor area below the exit storey into upper storeys. This requirement is applicable to elevator shafts and other shafts in highrise buildings. Depending on the number of levels below grade, the Building Code requires a two-hour rated elevator vestibule on the levels below the lowest exit storey.

For all other buildings (non-highrises), measures to limit smoke movement are not required by the Building Code.

For all types of buildings, Part 3 requires a pressurized vestibule between a parking garage and an elevator shaft to limit the potential migration of carbon monoxide.

Therefore under the current Building Code provisions a highrise building requires review of both smoke and carbon monoxide control, and a non-highrise building requires review of carbon monoxide control only.

Despite the above provisions the Building Code, by requiring only fire dampers at the vent openings between the parking garage and elevator machine room, does not clearly address smoke management and carbon monoxide management.

Possible Solutions

Notwithstanding the Building Code’s lack of clarity on smoke and carbon monoxide management, under the prescriptive requirements of Part 3 such an approach should be developed to apply to all parkade elevator machine rooms. There are two possible options for consideration:

Option 1

Ventilation to the elevator machine room will consist of a supply duct (100% exterior air) and an exhaust duct that discharges directly to the exterior. Fire dampers are still required where the ducts penetrate the elevator machine room. The ducts need not be enclosed in a rated shaft.

Option 2

Ventilation to the elevator machine room will consist of a supply duct (100% exterior air) and an exhaust fan to the parking garage with a fire damper. The fan should be on continuously, on emergency power, to avoid air movement from the parking garage to the machine room. A fire damper is still required where the duct penetrates the elevator machine room. The duct need not be enclosed in a rated shaft.

Other Considerations

The air supply duct for the elevator machine room may ultimately serve the elevator shaft through the openings between the machine room and the shaft, and air movement may be further assisted by the stack effect. This aspect, and the location of the air supply duct, may require more attention as the intake may introduce contaminated air into the building through the elevator shaft. In addition, consideration should be given to addressing negative pressures created in the elevator shaft.

Caution Advised on Non-Endorsed Letters of Assurance

APEGBC’s Consulting Practice Committee has learned that some municipalities continue to formulate their own Letters of Assurance, which are not endorsed by APEGBC, to augment or in some cases replace the standard forms required by the BC Building Code.

Because of this problem, in October 2003 APEGBC sent a letter to the Building Officials Association of BC (see www.boabc.org/_pdfs/news_wht_lttrso.pdf) requesting that they advise APEGBC of such documents so that the Association can have the opportunity to comment on them.

In addition, a Technical Bulletin clarifying the roles and responsibilities of professional engineers and geoscientists with respect to Letters of Assurance was published in the July/August 2002 issue of Innovation (page 52) at www.apeg.bc.ca/innovation/archives.html.

Members are strongly advised to use caution when signing Letters of Assurance that have not been endorsed by APEGBC. Currently, the only Letters of Assurance endorsed by APEGBC are those issued in the latest version of the BC Building Code, Vancouver Building Bylaw and Bulletin K: Letters of Assurance and Due Diligence (Schedule S — Specialty Engineer Assurance of Professional Design and Field Review) in APEGBC’s Guidelines for Professional Excellence and available at www.apeg.bc.ca/library/library/guidelines/bulletink.html.

In some instances, the wording of these letters may not be acceptable to the member’s professional liability insurance provider and could void this insurance coverage. It would be prudent for members to consult with their insurers to ensure that their coverage is not invalidated by signing Letters of Assurance that contain wording not formally endorsed by APEGBC.

In the event that the professional liability insurance provider advises that the member’s coverage may be void if they sign the particular Letter of Assurance in question, this should be brought to the attention of the relevant authority having jurisdiction.