Design and construction complexities: Centre Block project due diligence report: Cost report

Design and construction complexities

Heritage rehabilitations, especially one of this magnitude, are unique, highly complex, and costly undertakings. The Centre Block is both a working parliamentary complex and a public building. To carry out these twin responsibilities into the 21st century and beyond, it requires a wide range of modern interventions that require careful planning and execution while respecting and conserving the building’s highly decorative heritage attributes.

Turner & Townsend has surveyed the industry to identify similar projects that are currently underway or in the planning phase. Projects are unique in their scope and based on the industry scan and the table below, Centre Block is the most complex.

Key Assessment Program Findings

Given the complexity and scale of this project, Public Services and Procurement Canada completed a comprehensive assessment program with the objective of reducing program risk and informing the schematic design and downstream construction strategies. The key Assessment Program Findings are:

Heritage & Architecture

• Comprehensive Building Information Modeling (BIM) for use by the design team
• Foundation of the conservation strategy

Archeology

• Improved archaeologic record of the site
• More than 90,000 artifacts found and catalogued

Environmental

• Basis for a thorough Environmental Effects Evaluation for the project and Environmental Management Plan to support the construction period
• Complete baseline against which to measure sustainability initiatives

Designated Substances

• No exaggerated conditions found in the existing building
• Solid record to manage any residual substances that will remain encapsulated in some building elements
• Enabled development of Designated Substance Strategy

Structural

• Building structural strength is better than anticipated, which will allow optimization of the design intervention

Geotech/Civil

• Confirmed Class A rock formation that will allow optimized foundation and structural design
• Thorough understanding of the state of civil/municipal infrastructure connections serving the building

Mechanical & Electrical

• Confirmed conditions for heating, cooling, and humidity required to maintain heritage fabric during construction
• Limitation for many services
• Confirmation of constraints and requirement for a new M&E distribution strategy

Some of the key challenges and complexities of the program, which are also important cost drivers, are outlined in the sections below.

Heritage

While many building modernizations have heritage elements that must be considered, the level of decorative heritage and architectural elements that are intrinsic to the Centre Block’s building fabric is comprehensive and unprecedented within Canada and is rare globally. The building itself is a work of art with over fifty high-heritage rooms that contain unique and important decorative elements ranging from the Senate and House of Commons Chamber ceilings, to Arthur Crisp’s seventeen murals, to stained and leaded glass windows, to millwork, decorative plaster, and lighting.

Comprehensive assessment, custom design, and careful construction is required to integrate modern elements appropriately into the heritage fabric. As such, the process to modernize the building and conserve its heritage elements takes more time, and there is a cost premium. For example, the integration of new building and structural systems require opening walls that are, themselves, heritage assets. The modernization of the Senate Chamber includes the conservation of its gold leaf and decorative hand stencilled plaster ceiling in situ, while also structurally reinforcing the ceiling.

Not only are heritage rehabilitations more costly, but they are also more difficult to compare because of their uniqueness and the distinct condition of each individual heritage element. For example, the conservation strategies and the resultant costs to conserve the ceilings of the Senate and House of Commons Chambers are very different than for that of the Crisp Murals located in the Centre Block and quite different again for the Norman Rockwell mosaic at the United Nations Headquarters.

Senate Chamber and Galleries

The Senate Chamber, located on the east side of the Centre Block, is where the Queen and the Governor General come to address Parliament and give Royal Assent to bills. The Chamber Galleries provide space for both the public and the media to observe Senate proceedings. The number of Senators does not increase with population growth and is stable at 105.

This high-heritage space will be conserved and modernized to improve the access of Canadians to the democratic process including reconstruction of the Chamber Gallery to provide full universal access as well as the incorporation of modern technology, including broadcasting, within its current footprint. The hard construction cost for the renovation of this functional space is in the order of $60 million.
Source: Senate of Canada website

Structural complexity and building system upgrades

The Centre Block has both a steel structural framework and load-bearing masonry. The building will require structural upgrades to achieve modern code requirements, but a comprehensive seismic upgrade is also required to meet modern building code requirements. Of note, Ottawa is in the second most active seismic zone in Canada.

The seismic approach for the Centre Block will include a base isolation solution to address seismic requirements instead of a traditional seismic structural upgrade. While the technology is proven and used frequently in the Asia-Pacific region as well as on the West coast of North America, this is the first time that this approach will be utilized in the Parliamentary Precinct. Using base isolation technology reduces costs by approximately $200M, but perhaps even more importantly avoids a broad range of structural interventions that would negatively impact the Centre Block’s heritage fabric. Base isolation will also perform better in a seismic event, reducing the potential for damage to the Centre Block during an earthquake.

Structural and seismic upgrades are nonetheless complex and the possibility of additional costs due to unforeseen existing conditions is typically much higher in heritage projects. Moreover, a considerable amount of complex engineered temporary support measures and monitoring are required to ensure the Centre Block and Peace Tower are not impacted during construction. These considerations must be factored into the establishment of an appropriate construction contingency.

In addition to structural and seismic upgrades, modern, purpose-built building systems will need to be integrated into both the Centre Block and the Parliament Welcome Centre. In the Centre Block, this includes the complete removal and replacement of fire protection, mechanical and electrical systems, plumbing, elevators, as well as a new Information Technology (IT) and security backbone. Determining the new distribution of these systems within a building that has significant space restrictions is a complex challenge. Moreover, these new systems must weave seamlessly into the existing heritage fabric of the building. Many of these design elements will be finalized during the design development phase of the program. As a result, an appropriate design contingency has been included in this cost estimate to support the design development process.

How base isolation works

Security

Both the global and domestic security environment has resulted in a continual increase for security infrastructure within the Parliamentary Precinct over time with the core objective to protect Canada’s democratic institutions, the people working there and those visiting. At the same time, the Parliamentary Precinct welcomes millions of visitors a year and many of those visitors come to see the Centre Block and to engage in Canada’s parliamentary democracy. Implementing a security approach that balances the needs of a working legislative building with the openness of Parliament is critical.

Security requirements for the Parliamentary Precinct, including the Centre Block and Parliament Welcome Centre, are established by Parliament and are based upon comprehensive threat risk assessments also developed by Parliament. While significant collaboration and progress has been made with the administrations of the Senate, House of Commons, and Parliamentary Protective Service to advance the security strategy and requirements for the Centre Block and Parliament Welcome Centre, these requirements are still in the process of being finalized and range from structural enhancements to scanning capabilities to surveillance and cyber security. Planning assumptions and benchmarking with previously completed projects within the Parliamentary Precinct have been used to establish a notional allowance for security. The finalization of security requirements as well as any subsequent changes will have a direct impact on program scope and schedule.

Security infrastructure and protection procedures are multi-faceted, campus-focused, and layered. Unlike other areas of the program, the security environment is ever-evolving and security requirements are highly susceptible to change based on both emerging threats and availability of new technological solutions. This type of change was experienced for projects in the Parliamentary Precinct, including the West Block and Senate of Canada Building, as well as on international projects such as the United Nations Headquarters. Changes in building security requirements during construction caused adverse consequences to project cost and schedule.

As a result, the establishment of appropriate design and construction contingency as well as risk allowances is important to try and mitigate this risk, as successfully managed on the West Block and Senate of Canada Building.

Security and the United Nations Headquarters modernization

In 2015, the United States General Accountability Office (GAO) reported the project to modernize and restore the United Nations (UN) headquarters Complex was 3 years behind schedule and $379 million (US) over budget, largely due to enhanced security measures adopted during the project.

During construction, the UN General Assembly approved new security requirements. The enhanced security alone delayed the project by up to one year.
The enhanced security requirements were added to the project in 2011 due to increasing threats the UN faced globally. During the project, the UN, the US Government, and the City of New York identified additional security enhancements not envisioned in the original modernization plan.

Source: United States Government Accountability Office, Report to the Chairman, Committee on Foreign Relations, United States Senate, “United Nations Renovations: Original Scope Reduced and Project Over Budget, but Lessons Learned Could Improve Future Projects,” May 2015

Designated substances

The Assessment Program has enabled the identification of the levels and location of designated substances within the Centre Block. The abatement program, commenced in lower-impact heritage areas where removal is easier, is now approximately 50% complete having removed approximately 4000 metric tonnes of designated substances (largely asbestos) to date. Current findings suggest that the investment in the assessment program has improved accuracy of the design documents, which is resulting in fewer change orders during construction execution. However, demolition and abatement of higher heritage areas within the building is now commencing, which is more labour-intensive and more costly. This work carries an increased possibility of uncovering unforeseen conditions. This potential has been factored into the establishment of the construction contingency should additional abatement be required. The West Block, which did not benefit from a comprehensive assessment program, required a much higher amount of designated substance abatement than originally anticipated and a resultant higher use of contingencies for that portion of work.

Unforeseen conditions

The Centre Block was constructed quickly, in wartime, 100 years ago. Accurate and detailed documentation, including “as-built” drawings that include exact dimensions and conditions of the work completed during the original construction of the building are not available. As cited earlier in this report, Public Services and Procurement Canada has conducted the most comprehensive assessment program undertaken in the Parliamentary Precinct to date to reduce program risk and inform the design process. Although the Assessment Program has greatly informed the design process, unforeseen conditions still represent a significant unknown risk, for which the cost and schedule implications cannot be completely quantified at the outset of the project. As a result, an appropriate amount of construction contingency has been established to address unforeseen conditions. Public Services and Procurement Canada (PSPC) will need to continue to closely monitor changes driven by unforeseen site conditions to mitigate their impact as much as possible.

While Centre Block has not yet experienced many unforeseen site conditions, one such recent example is the rubble foundation at the east side of the Centre Block, which when exposed in support of excavation activities, was found to be in poorer condition than expected. This resulted in the need for additional reinforcement in this area that had to be completed before adjacent excavation activities could commence. This work was funded through construction contingencies provided within the initial allocation of funds to cover planned expenditures to 2021 to 2022.

House of Commons Chamber

The House of Commons Chamber accommodates the elected House of the Canadian Parliament and is located on the west side of the Centre Block building. The high-heritage space supports both ceremonial procedures and core business such as debate and passage of legislation to chart the democratic course of the country.

With a view to protecting heritage, the House of Commons Board of Internal Economy decided not to expand the size of the Chamber and focus modernization efforts on the existing Chamber. To accommodate the growth of Members of Parliament over time, alternate seating arrangements are being investigated.

This high-heritage space will be modernized to improve the access of Canadians to the democratic process including reconstruction of the Chamber Galleries to provide full universal access as well as the incorporation of modern technology, including broadcasting, within its current footprint construction cost for the renovation of this functional space is in the order of $113 million.

Another key aspect is the conservation of high-heritage components such as leaded glass and stained-glass windows, teak and ebony flooring, original heritage light fixtures, decorative woodwork including panelling and doors, Tyndall stone walls and carvings, and decorative plaster and the painted linen ceiling.