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Ensure Building Code Compliance Life Safety Evaluation Precedes Renovations
September, 2008
By Gary Robitaille
Renovations or a planned change in major occupancy often trigger requirements for existing buildings to comply with current building codes. This will depend on the degree of alterations to existing building systems and how they may affect building performance and/or create hazards for occupants in buildings.
Life safety upgrades and investment will likely be required for building renovations and material alterations and possibly even for repairs to an existing building. Building owners may need to review and evaluate early warning and evacuation systems to determine if they comply with code requirements as a result of changes to an existing building.
The following types of issues often arise during renovations of existing buildings or suites:
( Insufficient exit/egress;
( Dead end corridors;
( Inadequate washroom facilities;
( Portions of a floor area or room with inadequate fire alarm audibility (possibly due to introduction of enclosed office spaces or changes in a manufacturing process);
( Sprinkler head obstructions (proximity to walls or bulkheads);
( Inadequate fire hose coverage or restricted access to fire hose cabinets;
( Installation of door security hardware restricting access to exits;
( Availability of crossover floors. Access to emergency exits through single-tenant floors with no public corridor; and/or
( Inadequate legacy fire protection systems. Examples include inadequate fire alarm system zoning, lack of fire and smoke detection devices, unsprinklered areas.
RECENT UPDATE FOR ONTARIO
The Building Code spells out the conditions that necessitate upgrades and provides guidance on how to comply, including compliance alternatives for scenarios where it may be structurally implausible to meet code standards or where such alterations could undermine the architectural significance of a heritage building. Possible compliance requirements for additions, renovations and repairs are found in Part II of the Ontario Building Code (OBC).
The Building Code defines a building system as a combination of elements or components that form a complete major division of construction in the design of a building or part of a building. This could include, for example, a structural system, a fire alarm and detection system, a corridor and stair system, or a standpipe and hose system. Any or potentially all of these systems could be affected in a renovation.
The OBC classifies existing buildings based on construction and occupancy. The construction of a building is determined on the basis of a construction index and occupancy is determined on the basis of a hazard index.
BASIC & EXTENSIVE RENOVATIONS
When an existing building is subject to extension, material alteration or repair, the proposed construction must comply with OBC Section 11.3 addressing Proposed Construction. Where an existing building system is materially altered or repaired, the performance level of the building after the material alteration or repair is required to be at least equal to the performance level of the building prior to the material alteration. The Code recognizes two types of renovations: Basic and Extensive.
With a basic renovation, construction may be carried out to maintain the existing performance level of all or part of a building. This includes the reuse, relocation or extension of the same or similar material components, to retain the existing character, structural uniqueness, heritage value or aesthetic appearance of all or part of the building. This applies if the construction will not adversely affect the existing early warning evacuation systems, fire separations or structural adequacies to create an unhealthy environment in the building.
Renovations are deemed extensive where existing material walls, ceilings, floor assemblies or roof assemblies are substantially removed in an existing building. New material, walls, ceilings or floor assemblies, structural and fire-resistance elements must be constructed in compliance with the requirements of the other Parts of the Code.
The performance level of the existing building must be evaluated and compensating construction is required to be undertaken where the performance level may be reduced due to proposed alterations or repairs, in accordance with OBC Part 11.4. for Performance Level Evaluation and Compensating Construction.
DETERMINING PERFORMANCE LEVEL
The performance level of an existing building may be reduced in cases where, after proposed construction in all or part of an existing building:
1. a major occupancy will change to a different major occupancy;
2. the occupant load will increase by more than 15%; or
3. the live load will increase due to change in use within the same major occupancy, an existing structural floor, roof or framing system and their supporting members after the construction are not adequate to support the proposed dead loads and live loads.
Where the performance level of an existing building is reduced under Sentences 11.4.2.2.(1), (2) or (3), the building must be evaluated and the early warning and evacuation systems are required to be upgraded in conformance with the requirements of Table 11.4.3.3. This outlines requirements for early warning and evacuation systems evaluation and upgrading, specifically referring also to compliance alternatives.
REVIEW REQUIRED
The following applies to a change from a major occupancy to one of equal or lesser hazard and an increase in occupant load by 15% or less. A review for early warning and evacuation would include:
* access to exit width
* exit width based on occupant load
* exit signage
* lighting of exits
* lighting of access to exits
* emergency lighting
* fire alarm system
* smoke alarms
* travel distance
* number of exit doorways
* door release hardware requirements.
All deficiencies are required to be upgraded
Where there is a change from a major occupancy to one of greater hazard and an increase in occupant load greater than 15%, a review for early warning and evacuation is required as noted above in addition to the following:
(smoke control measure, and at least one elevator to permit the transport of fire fighters to all floors in hotels whose floor level is more than 18 metres high measured between the grade and floor level of the top storey served.
All deficiencies are required to be upgraded.
COMPLIANCE ALTERNATIVES
OBC Part 11 requires measures to compensate for the reduction in the performance level of an existing building. Compensating measures are described in the Code as compliance alternatives relative to a specific type of occupancy.
The Code prescribes compliance alternatives that may be substituted for requirements contained in Parts 3, 4, 5, 6, 7 or 8 of the OBC where the Chief Building Official is satisfied that compliance with the requirements is impractical because of construction difficulties or it is detrimental to the preservation of a heritage building.
Compliance alternatives are listed in Table 11.5.1.1.A with respect to Part 3 of the Building Code for assembly occupancies, Table 11.5.1.1.B is applicable to Care and Detention occupancies, Table 11.5.1.1.C for Residential occupancies, Table 11.5.1.1.D&E for Business/Mercantile occupancies, and Table 11.5.1.1.F for Industrial occupancies.
Identifying issues early during the design process provides an opportunity to have discussions with the Authority Having Jurisdiction for the purpose of proposing methods/alternative measures and solutions to those prescribed by the Code.
Gary Robitaille, B.Tech., A.Sc.T, is a Senior Associate with LRI, a consulting engineering firm specializing in fire protection engineering services and Building and Fire Code consulting. For more information, see the web site at www.lrifire.com.
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