A renovation begins as one scope of work and occasionally becomes another. The project you planned gets approved with conditions, and suddenly the budget has to absorb a sprinkler system, an upgraded exit, or accessibility work nobody costed.

That outcome is usually predictable. Understanding what actually triggers a code upgrade lets you plan for it rather than discover it at permit review.

The principle behind existing buildings

Buildings are generally permitted to remain as they were built, under the code in force at the time. That acquired status is what allows older buildings to keep operating without being brought up to current standards every time the code changes.

What ends that protection is change. When you alter a building, the altered portions have to comply with the current code, and depending on the nature of the change, the requirement can extend well beyond the area you touched. The BC Building Code and, within the City of Vancouver, the Vancouver Building Bylaw both contain provisions dealing specifically with existing buildings, and the interpretation of those provisions is where most disputes with authorities having jurisdiction happen.

Change of use is the biggest trigger

Nothing generates code upgrade requirements faster than changing what a building is used for. Occupancy classifications carry different requirements for exiting, fire separations, structural loading, ventilation, plumbing fixtures and accessibility.

Converting warehouse space to offices, offices to a daycare, retail to a restaurant, or any industrial space to assembly use will pull in requirements the building was never designed for. Occupant load frequently increases, which cascades into exit width, exit quantity and washroom fixture counts.

This is the change most often underestimated, because the physical work can look modest while the code implications are extensive.

Increasing occupant load

Even without a formal change of occupancy, packing more people into a space triggers requirements. Occupant load drives the number and width of exits, travel distances, fire alarm requirements, and plumbing fixtures.

Adding seating to a restaurant, converting storage to workspace, or reconfiguring an open office to higher density can all cross a threshold that was not crossed before.

Structural work and building area

Additions, new openings in loadbearing walls, mezzanines, rooftop equipment and anything that changes how loads travel through a structure bring current structural requirements into play, including current seismic provisions. In much of British Columbia that is a significant consideration rather than a formality.

Increasing building area or height can also change the construction requirements that apply to the building as a whole, including combustible versus noncombustible construction and sprinkler requirements.

The systems that commonly get pulled in

Several requirements surface repeatedly during renovation review:

• Sprinkler systems, where area, occupancy or height thresholds are crossed
• Fire alarm systems requiring upgrade or extension into renovated areas
• Fire separations and closures between occupancies or between suites
• Exiting, including exit width, number of exits and travel distance
• Emergency lighting and exit signage
• Accessibility, including barrier-free paths of travel and washrooms
• Ventilation rates tied to the new use
• Integrated systems testing where multiple life safety systems interconnect

Accessibility deserves particular attention, because the requirement is frequently triggered by work that seems unrelated to it, and because retrofitting an accessible path of travel into an existing building is rarely cheap.

Where alternative solutions come in

Prescriptive code requirements assume a typical building. Existing buildings frequently are not typical, and literal compliance is sometimes physically impossible or wildly disproportionate to the risk being addressed.

That is what the alternative solutions path exists for. An alternative solution demonstrates that a proposed design achieves the level of performance the code intends, even though it does not follow the prescriptive route. It requires engineering analysis and documentation, and it has to satisfy the authority having jurisdiction, but it is often the difference between a heritage conversion proceeding and stalling. This is a core part of our building code consulting work.

Get the code review done early

The expensive version of this process is discovering the requirements after design is complete. A code review at concept stage identifies what will be triggered, what it will cost, and where an alternative solution may be worth pursuing, while the design can still absorb the answer.

Ratio Code Consultants is registered with Engineers and Geoscientists BC and works across the BC Building Code Parts 3 and 9, the Vancouver Building Bylaw, and the BC Fire Code. You can see the range of services we offer and examples of our past projects, from school additions to data centre and office renovations.

If you have a renovation in planning, call 604-921-3922 or get in touch before the drawings are finalized.