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Balanced Code Provisions for
Residential StructuresAlliance for Concrete Codes
and Standards (ACCS)Presented By:
Alliance for Concrete Codes and Standards (ACCS)
American Concrete Institute American Concrete Pipe
Association American Society of Concrete Contractors Architectural Precast
Association Concrete Foundation
Association Concrete Reinforcing Steel
Institute Insulating Concrete Form
Association
National Precast Concrete Association
National Ready Mixed Concrete Association
Post-Tensioning Institute Portland Cement Association Precast/Prestressed Concrete
Institute Tilt-up Concrete Association Wire Reinforcing Institute
IntroductionOutline
Fire Loss Building Codes Balanced Design Benefits of Concrete
in Fire Costs Associated with
Concrete Construction Take Action! Conclusions
Limitations to the Building Code
Recent building code revisions have reduced the use of passive fire protection and provided an over-reliance on active fire protection system sSprinkler trade-offs: the concept of
exchanging established passive fire containment code provisions for active protection
Sprinkler system reliability unknown
What is fire safety?
Fire safety is a component of Building Safety. It concerns safety measures to prevent the effects of fires and is the result of proper use of fire protection measures.
Fire Loss in the United States
Fire loss
Fire Loss More than 4,000 people die in fires each year, with one death every
130 minutes. Fire kills more Americans than all natural disasters combined.
Approximately 85 percent of fire deaths occur in homes. Fire strikes approximately 86,500 apartments, 2,000 hotels and motels, and 740 dormitories annually.
Each year, fire departments are called to more than 1.7 million fires, with a fire call received every 18 seconds. There are nearly 510,000 structure fires each year, with one occurring every 62 seconds.
Fire causes more than $11 billion in property damage each year, with about $9.5 billion resulting from structure fires. Half of the total property damage occurs in residential properties.
Building and Fire Codes
Building and Fire Codes are state or jurisdiction specific
Codes are the minimum requirements – “the basement”
Building and Fire Codes
What is a Building Code?A building code is the minimum acceptable standard used to regulate the design, construction, and maintenance of buildings for the purpose of protecting the health, safety, and general welfare of the building’s users.
Up To Date Building CodesBuild safe buildingReduce deaths, injuries and property damagePreserve the built environmentReduce public and private disaster aidMaintain employment and businesses Level playing field for engineers, builders and
suppliersProvide economies of scaleMaintain quality of life and property values
Building and Fire Codes
Insert Building and Fire Code information for location being presented
Balanced DesignBalanced design re-established the importance of passive design,
including compartmentalization, in combination with active design, to deliver a more comprehensive fire protection system.
Active Fire Protection: Fire protection systems that must beactivated to perform, such as sprinklers and smoke detectors.
Passive Fire Protection: Fire resistance provided by elementsthat inherently resist fire, such as non-combustible precastconcrete, concrete and masonry block.
Balanced Design: A Combination of active and passivedesign elements, as well as the concept ofcompartmentalization, to greatly enhance fire protection at aminimum cost.
Balanced Design
TotalFire Protection
ActiveFire Protection
PassiveFire Protection
Balanced DesignActive Fire Protection
Smoke detectors Sprinklers Duct detectors Fire alarms
Passive Fire Protection
Fire rated walls Fire rated floors Fire rated separations
Role of Compartmentation Compartmentation
acts to contain fires to a specified area of the building or structure
Without compartmentation, fire may spread from one room or building to a another
Role of Sprinklers
Fire Sprinklers act to extinguish a fire after a specified temperature is achieved in the upper gas layer
Role of SprinklersNFPA standards
NFPA 13 Standard for the Installation of Sprinkler Systems
NFPA 13D Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes
NFPA 13E Recommended Practice for Fire Department Operations in Properties Protected by Sprinkler and Standpipe Systems
NFPA 13R Standard for the Installation of Sprinkler Systems in Residential Occupancies up to and Including Four Stories in Height
Why sprinklers may fail Natural Events (earthquake, tornado, etc.) Terrorist Events Inadequate water pressure Human Error Lack of maintenance Installation Error Wrong sprinkler for occupancy/fire Coverage Issues Building under construction Other
Options for Non-combustible construction
cast-in-place hollow-core precast concrete floors,
ceilings, and roofs cast-in place
concrete precast concrete Concrete masonry
walls
Advantages of Non-combustible construction for owners/developers
Speed of construction Faster sales and re-sales Lower operating costs Lower insurance costs Lower maintenance costs Lower energy costs Community acceptance
Lowest life-cycle costs Higher appreciation Attracts quality oriented
occupants Appeals to investors Proven performance Resistant to seismic and
high wind damage
Advantages of Non-combustible construction for occupants
Fire safe non-combustible construction
Does not burn Does not produce smoke,
fumes or gases Does not add fuel to the
fire Provides minimum two-
hour separation between units
Serves passively for the life of the building
Lower insurance costs Needs no testing or
inspection No bouncy or creaky
floors Superior acoustic
qualities Security for occupants
and contents
Advantages of Non-combustible construction for communities
Lower risk and exposure for the fire service
More efficient use of fire services
Construction does not add fuel to the fire
Fire is contained Adjacent units are protected
Structural collapse is unlikely Provides quality community
asset for many decades Community recognized for its
fire safe construction Provides a stable tax base for
the community Attracts long term investors to
the community.
Fire Containment Fire Containment is
the last line of defense should sprinklers fail
To be effective, walls and floors/ceilings providing compartmentation should be of non-combustible construction with at least 2 hours of fire resistance.
Firefighter Safety A concrete structure can utilize fire
rated concrete walls to create compartmentation. The combination of concrete columns, beams, flooring, ceiling and wall elements breaks up each level’s space into smaller, self-contained modules that minimize the chance of fire spreading to adjacent units
The containment of fire in these small spaces makes entry safer for the firefighter and maintains that building collapse is rare
Fire Resistance Concrete has history of good performance in fire Concrete is non-combustible and has low thermal
conductivity Concrete maintains cool inner core during many fires
which maintains load
Fire Resistance
Structural Design LoadLive Load + Dead Load + FIRE
Goal of Fire Resistance StructuresMaintain structural stabilityReduce spread of fireExperience total burnout without collapse
Concrete at elevated temperatures
250 – 420 °C: Some spalling occurs
300 °C: Loss of strength begins 550 – 600 °C: Cement based
materials experience creep and lose their load bearing capacity
600 °C: Greater than this temperature, concrete is not functioning at its full structural capacity
900 °C: Temperature of Flame
Fire Resistance
The term "fire-resistance" designates the ability of a laboratory-constructed assembly to contain a fire in a carefully controlled test setting for a specified period of time.
Harmathy’s Rules of Fire Endurance
ACI 216 ACI 216.1-97: Standard Method for Determining
Fire Resistance of Concrete and Masonry Construction Assemblies
ACI 216
Determines Fire Resistance through one of four methods
1. Qualification by Testing2. Calculated Fire Resistance3. Approval through Past Performance4. Engineered Analysis
Qualification by Testing The most common test method for determining
fire resistance in the United States is the ASTM Standard E 119 Test Methods for Fire Tests of Building Construction and Materials.
ASTM E119
Three End Points to fire test:1. Ignition of cotton waste
supported on the member surface that is away from the surface directly exposed to fire.
2. A temperature increase of 325 F at any point or 250 F on average on the unexposed surface (the heat-transmission end point).
3. Inability to carry the applied design load (i.e., structural collapse).
ASTM E119
Insert video
Calculated Fire Resistance
The fire resistance associated with an element or assembly shall be deemed acceptable when established by the calculation procedures in ACI 216
Plain reinforced concrete bearing and non-bearing walls, floors and roof slabs shall conform with the minimum thickness provided in ACI 216 Table 2.1
Calculated Fire ResistanceACI 216.1-97 Table 2.1. Fire Resistance of singular layer concrete walls, floors, and roofs
Aggregate Type
Minimum equivalent thickness for fire resistance rating, in.
1 hr 1 ½ hr 2 hr 3 hr 4 hr
Siliceous 3.5 4.3 5.0 6.2 7.0Carbonate 3.2 4.0 4.6 5.7 6.6Semi-lightweight
2.7 3.3 3.8 4.6 5.4
Lightweight 2.5 3.1 3.6 4.4 5.1
Effect of Aggregate
The choice of aggregate directly impacts the performance of concrete during a fire
Wood FireFire Resistance of Wood is significantly lower than that of concrete
Fire Resistance
Strength at elevated temperatures
Fire Spread
Concrete will not ignite. The fire’s spread is slowed and its damage is minimized.
This ability to resist fire creates more time for detection, evacuation and suppression—the three key ingredients for minimizing damage and injury during a fire.
Flame Spread
Concrete will limit flame spread
Interior FinishThe majority of fire deaths in a residential home is due to
toxic products of combustion from interior finish
Toxicity Most fire deaths result not from
heat or burns but from inhaling smoke and toxic gasses.
Gases produced in a fire include: water, CO2, styrene, bromide, and CO
Concrete does not produce toxic gases when involved in a fire
Compartmentation with concrete construction reduces the spread of toxic gas or smoke.
CostsFSCAC Cost Comparison Study
Conventional wood framing with wood floor system (Type V-B Construction)
Conventional wood framing with wood floor system (Type V-A Construction)
Light gauge steel framing with cast-in-place concrete floor system on metal form deck
Insulated concrete form exterior walls with interior bearing walls constructed of
concrete masonry units and precast concrete floor system
Load bearing concrete masonry with precast
concrete floor system Load-bearing concrete
masonry with cast-inplaceconcrete floor system
Precast concrete walls with precast concrete Floor system
Insulated concrete form walls with precast concrete floor system
Insulated concrete form walls with cast-inplace concrete floor system
The building construction types, designed using the provisions of the 2003 International Building Code, included:
Cost Study Results
The study provides the relative cost as a comparison to wood frame as a baseline of 100%, indicating increases or decreases relative to the baseline. Cost percentages shown below are examples of those provided by the complete study.
Insurance Benefit With increased emphasis on risk avoidance in the insurance
industry, property insurers and risk insurance managers have noticed the fire-resisting advantages offered by non-combustible construction
Source: Concrete & Masonry Industry Firesafety Committee’s Fire Protection Planning Report No. 9
Ensure safer Buildings through code adoption
Adopt a model building code which supports the concept of balanced design Ensure building code does not depend fully on active
fire protection systems or incorporate the idea of “sprinkler trade-offs”
Support amendments to the code which allows for adequate passive fire protection design
Consider using concrete in the building design to provide excellent fire resistant construction
708.3 Fire-resistance rating. Fire partitions shall have a fire-resistance rating of not less than 1 hour.
Exceptions: 1. Corridor walls as permitted by Table 1017.1.
2. Dwelling unit and sleeping unit separations in buildings of Types IIB, IIIB and VB construction shall have fire-resistance ratings of not less than 1 /2 hour in buildings equipped throughout with an automatic sprinkler system in accordance with Section rated corridor as required by Section 903.3.1.1
ExampleHow to adjust existing building code to reduce sprinkler
trade-offs
Take Action! Find out which (if any!) building
code your state or jurisdiction currently enforces or adopts
Research whether the code adequately addresses the ideas incorporated in the balanced design approach
Contact your building code official or state representative and submit your concerns
Work with local groups for adoption of strict amendments ensuring balanced design and participate in the development of the model code process
Educate others on the benefits of concrete construction, passive fire protection and balanced design.
Conclusions Adequate building codes with a balanced design
approach can provide safe buildings for occupants, owners and fire safety officials
Concrete is a non-combustible building material that will
Limit flame spread Reduce costs Not produce toxic gases during fire Provide high fire resistance Ensure fire containment Construct at similar costs to other construction methods
Resources
Include links (websites, names, brochure, addresses, etc.)