Building Construction (IFSTA) Flashcards
Building codes regulate the type of construction based on the ___
Intended use, structure size, and the presence or lack of an automatic fire suppression system
Intended use is also called ___
Occupancy classification
The construction materials and their resistance to fire exposure determine the ___
Type of building construction
Two major model building codes in the US
- NFPA 5000 Building Construction and Safety Code
- International Code Council’s (ICC) International Building Code (IBC)
How many types of construction?
5
The types are further divided into subcategories, depending on the ___
Code and construction type
The construction material and their performance when exposed to fire define each ___
Construction type
Type I construction
Fire-resistive construction
Provides the highest level of protection from fire spread as well as structural collapse
Type I construction
All structural members are composed on noncombustible or limited-combustible materials with a high fire-resistive rating so that the structural members do not add to the fuel load
Type I construction
___ construction meet the criteria for Type I construction
Reinforced concrete, precast concrete, and protected steel frame
Type I construction provides ___ should a fire occur
Structural stability
Conditions that may be found by firefighters during a fire in Type I construction
- Compartments may retain heat
- Roofs may be difficult to penetrate
- Windows may be nonoperating
Type II construction
Noncombustible construction
Composed of materials that will not contribute to fire development or spread
Type II construction
The most common form of this construction type includes metal framing members, metal cladding, or concrete-block wall construction and unprotected, open web joists supporting metal roof decks
Type II construction
Type II construction is more prone to collapse than Type I because they are ___
Constructed of lighter-weight materials with lower fire-resistance ratings
Type III construction
Ordinary construction
Commonly found in mercantile, business, and residential structures, and older schools
Type III construction
This construction type requires that exterior walls and structural members be constructed of noncombustible or limited combustible materials. Interior walls, columns, beams, floors, and roofs are completely or partially constructed of wood
Type III construction
Conditions in Type III buildings that can influence fire behavior
- Void spaces inside the wooden channels that roof and truss systems create between wall studs are less protected and fire will spread through these spaces unless fire stops are installed
- Prefab wood truss systems similar to Type V may be found in Type III, and may fail quickly when exposed to fire
Renovation considerations
- Older Type III structures may have changes that created large hidden voids above ceilings and below floors
- Structural components may have been removed, reducing the load-carrying capacity of the supporting structural members
- Changes in building use or occupancy may result in additional loads the building was not designed to carry
Type IV construction
Heavy timber construction
Characterized by the use of large-dimensioned lumber or laminated wood
Type IV construction
In Type IV construction, it is the timber’s own ___ that reduces heat penetration to the inside of the beam
Char
Type IV structures are extremely stable and resistant to collapse due to the ___
Sheer mass of their structural members
In Type IV construction, the dimensions of all structural elements, including columns, beams, joists, and girders, must ___
Adhere to minimum dimension sizing
Exterior walls are constructed of noncombustible materials. Interior building elements such as floors, walls, and roofs are constructed of solid or laminated wood with no concealed spaces
Type IV construction
Small-dimension lumber glued together to form a laminated structural element
Glue-laminated or glulam elements
Glulam elements are commonly found in ___
Churches, auditoriums, and other large facilities with vaulted or curved ceilings
Glulam beams may fail when exposed to fire because the ___
Heat may affect the glue holding the laminates together
Type IV building conditions that can affect behavior during a fire
- High concentration of wood can contribute to the intensity of a fire once it starts
- Collapse of masonry walls can be caused by loss of structural integrity of timbers
Type V construction
Wood frame construction
The exterior load-bearing walls are composed entirely of wood. A veneer of stucco, brick, or stone may be constructed over the wood framing
Type V construction
Consists of framing materials that include wood 2 x 4 or 2 x 6 inch studs. The outside of the framing members is covered with any number of materials as exterior siding
Type V construction
Modern siding such as vinyl siding adds another ___ to the structural fire load
Petroleum-based fuel
Vinyl siding will ___
Produce dense, dark, oily, toxic smoke and will melt away from the side of the building
Some Type V structures will include 6” exterior wall cavities for ___
Increased insulation
Type V construction includes the use of a prefabricated wood truss system in place of ___
Solid floor joists
Difference between prefabricated wood truss system and solid floor joists
Creates a large, open void between the floors of a structure, rather than the closed channel system found in solid floor joists
Central piece of thin plywood or wood composite, glued to two 2x4 pieces
Wood I-beams
Structures that are built in a factory and shipped to the location on which they are to be installed
Factory-built homes
Homes that have an axle assembly under the frame
Mobile homes
Most common type of factory-built home
Manufactured home
Usually have wheels and a permanent steel undercarriage and are towed behind a transport vehicle for delivery
Manufactured homes
Manufactured homes conform to ___
US Dept of Housing and Urban Development standards, similar to Type V
Factory-built homes constructed before ___ have less fire resistance than current construction
1976
The use of lightweight building materials in factory-built homes makes ___ much easier
Forced entry
The modular section is transported to the site and then attached to a permanent foundation, which may include a full basement
Modular homes
Modular or section homes must comply with ___
The same local building codes as site-built homes
Assembled onsite from pre-constructed panels made of foam insulation sandwiched between sheets of plywood
Panelized homes
The panels in panelized homes normal dimensions
8’ x 40’
Consist of individual parts that are custom cut and must be assembled onsite
Pre-cut homes
Styles of pre-cut homes
- Pole houses
- Post-and-beam construction
- Log homes
- A-frames
- Geodesic homes
Modular core units such as bathrooms or mechanical rooms are constructed in the factory, moved to the site and assembled. Pre-constructed panels are then added to the modules to complete the structure
Hybrid modular structure
The ceilings in corridors that are designated as exit or egress passageways will have the same ___
Fire-resistance rating as the walls in that corridor
Ratings are indicated in ___
Hours
The material used to cover the floors in high occupancy structures is also rated to ___
Limit flammability in the corridor
Wall assemblies consist of a ___
- Bottom plate
- Top plate
- Vertical studs
- Horizontal braces
- Two surfaces made of gypsum or lath and plaster
Include the wall structure, doors, windows, and any other protected openings meeting the required protection rating criteria
Fire wall assemblies
Most difficult to penetrate when attempting to force entry into an area or to escape an area
Exterior walls and fire walls
Fire in basements can ___
Damage floor joists and load-bearing walls that support the upper floor and structure
Stairs can provide a flow path for the movement of ___
Air, fire gases, and smoke throughout the structure
Stair hazard
Present a fall danger during low-visibility conditions
Fires in basements may be more hazardous than in other compartments because of ___
Limited means on ingress/egress and limited ventilation
Types of basement
- Partially underground
- Fully underground
- Walk-out or daylight
The absence of dry wall effect on a basement fire
Reduces the fire resistance of the studs and joists, making the structural members part of the fuel load, potentially causing the floor above to collapse
Stairs that are part of the means of egress that provide protection for the occupants as they travel to safety
Protected or enclosed stairs
Stairs that are not required to be part of the means of egress system and typically connect no more than two levels
Access or convenience stairs
Protected stairs are enclosed with ___
Fire-rated construction, usually with either a 1 or 2 hour rating depending on the building height
Three prevalent roof types
- Flat
- Pitched
- Arched
Common roof styles
- Arched
- Mansard
- Sawtooth
- Shed
- Lantern
- Gambrel
- Hip
- Butterfly
- Pitched
- Flat
Flat roofs are commonly found on ___
Commercial, industrial, and multifamily residential structures, as well as on some single-family residences
Common features that penetrate flat roofs
Chimneys, vent pipes, shafts, scuttles, and skylights
___ may surround flat roofs
Parapet walls
Obstructions that may be located on roofs include ___
Water tanks, HVAC equipment, antennas, solar panels, signs
Types of arched roofs
- Ribbed
- Pleated barrel
- Diagonal grid (Lamella)
- Bowstring
Roof decking that consists of boards or planks set with a small space between them
Skip sheathing
OSB
Oriented strand board
The design of an arched roof depends primarily on the ___
Exterior walls to support the weight of the roof
Three main components of a roof
- Roof supporting structure
- Roof deck or sheathing
- Roof covering
Two general types of roof supports used in residential and commercial construction
Beams and truss assemblies
The sections of lumber located directly under the roof decking
Beams
On pitched roofs, the beams extend from ___
The ridge line or pole at the peak to each side wall
On flat roofs, the beams extend from ___
Wall to wall
Manufactured from plywood and are often used in conjunction with wood joists to support flat roofs and floors
Box beams and I-beams
Box beams and I-beams are also called ___
Wide flange beams
Roof truss assembly types
- Conventional framing constructed onsite
- Pre-manufactured in a factory and shipped to the site
Trusses constructed onsite consist of ___
Top and bottom chords and webbing that extend from the peak to the walls. A horizontal joist with supports between the joist and the rafters connects the ends
Wood trusses are assembled using ___
Metal gusset plates (gang nails) that only penetrate about 3/8” into the wood
Much like engineered box beams or I-beams, trusses created from engineered materials are also susceptible to ___
Early failure
The open web design of truss joints permits the ___
Rapid spread of fire in directions perpendicular to the truss joints instead of simply along the long dimension of the member
Truss types include ___
- Parallel chords
- Pitched chords
- Arched chords
The parallel chord truss is generally used to support ___
Flat roofs and floor assemblies
Manufactured from smaller pieces of wood or light gauge steel to form trusses that weigh less than traditional systems made from solid wood or heavy gauge steel
Engineered construction systems
Two of the most common types of engineered construction systems
Lightweight steel or wooden trusses
Made from long steel chords that are either straight or bent up to 90° with either flat or tubular members in the web space
Lightweight steel trusses
The portion of the roof between the roof supports and the roof covering
Roof deck
Types of roof decks
- Plywood sheathing
- OSB
- Wood tongue and groove
- Corrugated metal
- Sprayable concrete encapsulated polystyrene
- Reinforced concrete
- Double tee preformed concrete
Components of roof decks
- Sheathing
- Roof planks or slabs
- Purlins
Two basic types of concrete roofs common in north america
- Cast-in-place
- Precast
If a multistory building is to have a flat roof, the usual practice is to use ___
The same structural system for the roof and the floors
Placed into forms at the building site as a wet mass and hardens into prepared forms
Cast-in-place concrete
Permits the designer to cast the concrete in a wide variety of shapes
Cast-in-place concrete
Cast-in-place concrete roof does not develop its design strength until after it has been ___
Placed in the location where it will be used
Cast-in-place concrete does not develop its
Precast concrete roof units are widely used because they can be ___
Fabricated off-site and hauled to the construction site ready for use
These roofs have gypsum plaster and Portland cement mixed with aggregates, such as perlite, vermiculite, or sand to form lightweight concrete
Lightweight concrete roofs
Lightweight concrete roofs are usually finished with ___ to make them ___
- Roofing felt and hot tar
- Watertight
Lightweight concrete roofs are reinforced with ___
Steel mesh or rods
The part of the roof exposed to the weather
Roof covering
Roof penetrations can indicate ___
The location of some types of rooms such as bathrooms or mechanical spaces
Monitors, smoke and attic vents, scuttle hatches, and skylights may be used to gain access to ___
Attics and cocklofts
Common roof modifications
- Green roofs
- Cold roofs
- Photovoltaic roofs
- Rain or snow roofs
- Security
- Structural modifications
- Roof-mounted equipment
Involves the use of the roof surface of a building for a rooftop garden
Green roof
A rooftop garden constitutes a ___ on the roof structural system
Deadload
Under fire conditions, the increased load can accelerate ___
Structural failure
The deadload from a rooftop garden can weigh as much as ___
20 to 150 lbs sq/ft
Green roofs can interfere with ___
Ventilation practices and fire location indicators
Concerns with green roofs
- The effects of high-velocity winds and uplift wind pressures
- Roof drainage which can add weight to the roof creating a collapse hazard
- The exposure hazard that dry vegetation on the roof may create
- The need for a clear space between vegetation and fire walls that penetrate the roof
Generally found in cold, snowy climates to prevent ice damming and icicle formation at eaves
Cold roof system
Designed to prevent interior heat from escaping into the attic space, thus melting the snow on the roof
Cold roof system
Cold roof system installation
- Sheathing layer installed above the top chord of the truss or rafter
- Membrane installed above the sheathing layer to prevent condensation buildup
- Two layers of 1 x 4-inch parallel spacers are installed above the membrane to create a 3” void air space to act as insulation against warm air from the home
- Second layer of sheathing installed above the parallel spacers
- Roof covering system is installed next
PV
Photovoltaic
PV cell panels can be ___
Laid on top of a roof or embedded in the roof
If light is available, the PV cells will continue to ___
Produce power
On a PV array, the shock hazard due to application of water is dependent on ___
Voltage, water conductivity, distance, and spray pattern
On PV arrays, there is no single point of ___
Disconnect
What can reduce the power from PV to near zero?
Heavy, densely woven fabric and dark plastic films
Tactical considerations to mitigate shock hazards from PV installations
- Emergency disconnect and disruption techniques
- Severing of conductors
- PV power production during low ambient light, artificial light, and light from a fire
May be found on commercial buildings, schools, and residential structures. These assemblies are pitched roofs built over older flat roofs
Rain or snow roofs
Purpose of rain roofs
- Aesthetic purposes
- Leak prevention
- Directing moisture off the roof
- An alternative to repairing or resurfacing the original roof
Rain roofs are installed over mobile homes to provide ___
A more permanent appearance
Ventilating a rain roof will not remove smoke from within the structure until ___
The original roof is penetrated
The void that a rain roof creates can conceal a ___
Fire
Why should firefighters not enter the void area under a rain roof to cut a hole in the original roof?
- Become trapped in the void
- Be overcome by the heat and smoke trapped in the void
- Fall through a weakened original roof
- Be caught in an extreme fire condition as the heated gases mix with fresh air
___ may be installed for security purposes in rooftop skylights
Wired glass
Store owners may install ___ on the roof to prevent break-ins
Iron plates
Equipment mounted to roofs add to the ___
Load distributed on the roof, increase collapse hazards, and add to the obstructions that can affect ventilation efforts
Doors are a tool for ___
Fire and flow path control
Doors are generally classified by the way that they ___
Operate
Doors commonly used in modern construction
- Swinging
- Sliding
- Folding
- Vertical
- Revolving
Doors can also be classified by ___
Style and material
Most common metals used for doors
Aluminum and carbon steel
Door that rotates my means of hinges secured to the side jams of the doorway or on pivot posts supported at the top and bottom
Swinging door
A swinging door can be either ___
Single or double leaf
Single acting swinging door
Swinging in one direction
Double acting swinging door
Swinging in two directions
___ are usually required as exit doors in a means of egress
Swinging doors
Door suspended from an overhead track and uses steel or nylon rollers
Sliding doors
A sliding door usually has ___ to prevent the door from swinging laterally
Floor guides or tracks
A sliding door can be designed for ___
Surface sliding, pocket sliding, or bypass sliding
A sliding door eliminates a door swing that might ___
Interfere with the use of interior space
Door slides into a wall assembly
Pocket sliding door
Sliding doors are never allowed as part of a means of egress because ___
They slow the travel of people through the door opening
Door hung from an overhead track with rollers or glides, and folds into sections
Folding doors
A folding door can be either ___
Bifolding or multifolding
Folding doors may be found in ___
Residential occupancies, in places of assembly to divide large conference areas into smaller rooms, and as horizontal fire doors
A door that opens in a vertical plane
Overhead door or vertical door
Applications of vertical doors
- Loading dock doors
- Garage doors
- Freight elevator doors
- Fire doors protecting openings that are not part of the required means of egress
A vertical operating door can be ___
A simple single leaf, or it can consist of two or more horizontal panels
A door that operates vertically is usually provided with some type of ___
Counterbalance mechanism
The counter balance mechanism in vertical doors
Weights or springs
A vertical door can be raised ___
Manually, mechanically via chain hoist, or power-operated
Door constructed with three or four sections or wings that rotate in a circular frame
Revolving door
A revolving door is designed to minimize ___
Air flow through a door opening to reduce building heating or cooling costs
The wings of a revolving door are designed to ___ to provide an unobstructed opening
Collapse under pressure
How do revolving doors allow for collapse?
- Older doors use simple chain keepers or stretcher bars between the wings
- New models use spring-loaded, cam-in-groove hardware
- Most models employ a mechanism that allow the wings to open to a book-fold position when the wings are pushed in opposite directions
Door consists of vertical and horizontal members that frame a rectangular area. Thin panels of wood, glass, or louvers are placed within the framed rectangular area
Panel door
Consists of flat face panels that are the full height and width of the door. The panels are attached to a solid or hollow core
Flush door
Flush door is also called ___
Slab door
A flush door can be designed with openings to accommodate ___
Glass vision panels or ventilation louvres
Door formed with an interior core of laminated blocks of wood, particleboard, or a mineral composition. The core is covered with two or three layers of surface material, which is usually plywood
Solid-core doors
If a wood solid-core door is intended for exterior application where security is a concern, ___ may be attached to the exterior surface
A layer of sheet metal
Door constructed with spacers between the face panels to provide lateral support. The interior spacers consist of a grid or honeycomb of wood, plastic, or fiberboard
Hollow-core door
Hollow-core doors are ___ than solid-core doors
Lighter and less expensive
Hollow-core doors are usually used for interior applications because ___
They have minimal thermal or sound-insulating value
A solid-core door that has not been specifically designed as a fire door will act as a significant barrier to fire if it is ___ at the time of the fire
Closed
Glass doors are most commonly used in ___
Office and mercantile buildings
Glass doors can be either ___
Framed or frameless
Consists of a single sheet of glass to which door hardware such as handles are attached
Frameless glass door
Door in which glass is placed in and surrounded by a metal or wood frame with the required door hardware attached to the frame
Framed glass door
Glass doors must be made of ___
Tempered glass that resists breakage
Often used in framed glass doors to provide additional security
Various plastics such as Lexan or Plexiglas
Common type of metal door
Hollow door made from steel or aluminum
A hollow metal door can be either ___
Panel or flush
Normal hollow metal door thickness
1 3/4”
A flush door consists of smooth sheet metal face panels ___ thick. Vertical sheet metal ribs within the door spaced ___ apart separate the face panels of a steel door
- 1/20”
- 6” - 8”
___ can be placed between the ribs in a hollow metal door
Sound-deadening material
An aluminum flush door usually has a core of ___
Hardboard and honeycomb-patterned paper
A door made with two corrugated sheets has an interior core material such as ___
Styrofoam
Protect openings in fire-rated walls and block the spread of fire within a structure
Fire doors
Fire doors differ from ordinary doors in their ___
Construction, hardware, and the extent to which they may be required to close automatically
The construction and operation of fire doors depend on the ___
Type of occupancy, the amount of space around the door opening, and the required fire protection rating for the door
Most fire doors will be constructed of ___
Metal
Commonly used to protect a fire wall opening in an industrial occupancy or an opening in a wall separating buildings into fire areas
Overhead rolling steel fire door
Overhead rolling steel fire doors usually close ___
Under the force of gravity when a fusible link melts, but motor driven doors are available
An overhead rolling steel fire door is constructed of ___
Interlocking steel slats with other operating components such as:
Releasing devices
Counterbalance mechanisms
Governors
Wall guides
Usually held open by a fusible link, and slide into position along a track either by gravity or by the force of a counterweight
Horizontal sliding fire doors
Horizontal sliding fire doors are often found in ___
Old industrial buildings
Common type of sliding fire door
Metal-covered, wood-core door
The wood core in a sliding fire door provides ___, while the sheet metal covering ___
- Thermal insulation
- Protects the wood from the fire
Why does a metal-covered, wood-core sliding fire door usually have a vent hole in the sheet metal?
Wood undergoes thermal decomposition when exposed to heat, the vent hold vents the gases of decomposition
Metals used to cover a wood core sliding fire door
Steel, galvanized sheet metal, and terneplate
Terneplate
Metal composed of tin and lead
Fire doors made with terneplate are commonly referred to as ___
Tin-clad doors
Commonly used in stairwell enclosures or corridors that require a fire door
Swinging fire doors
Disadvantage of a swinging fire door
Requires a clear space around the door to ensure closure
A swinging fire door is a good choice when the door ___
Is located in a corridor where it must remain open during day-to-day operations
Fire doors can be either ___
Automatic or self-closing
Door normally held open and closes automatically when an operating device is activated
Automatic door
Door is normally closed and will return to the closed position if it is opened and released
Self-closing door
For a swinging fire door to close, ___
Some type of detection device must first sense a fire or smoke from a fire
Oldest and simplest detection device for a fire door
Fusible link
Advantage of fusible links
Inexpensive, relatively rugged, and easy to maintain
Disadvantage of fusible links
Slower to operate than devices that detect smoke or the rate of temperature increase
Advantage of smoke detector for a fire door
Closes more quickly, and permits easy testing
Disadvantage of smoke detector for a fire door
Costs more and requires periodic cleaning
Some fire doors are designed to close when any component of the ___ is activated
Fire alarm system
A window consists of ___
A frame, one or more sashes, and all necessary hardware to make a complete unit
Includes the members that form the perimeter of the window, and is fixed to the surrounding wall or other supports
Window frame
A fixed or movable framed unit that may be included within the window frame
Sash
The window frame is composed of ___
The sill, side jambs, and head jamb
Lowest horizontal member of the window frame and supports the weight of the hardware and sash
Sill
Glass in windows is called ___
Glazing
Glass in a window may be ___
Single, double, or triple-glazed
Windows can be broadly classified into ___
Fixed (nonoperable)
Movable (operable)
Windows that contain both fixed and movable characteristics are generally included in the ___ classification
Movable
Common movable window configurations
- Double-hung
- Single-hung
- Casement
- Horizontal sliding
- Awning
- Jalousie
- Projecting
- Pivoting
Has two sashes that can move past each other in a vertical plane
Double-hung window
A double-hung window is common in ___
Residential occupancies
___ hold a double-hung window in the desired position
Balancing devices
Balancing devices in a single or double-hung window
Counterweights, springs, or a spring-loaded coiled tap
Windows that use counterweights are found in ___
Old buildings
Has only one openable sash
Single-hung window
Has a side-hinged sash that is usually installed to swing outward. May contain one or two operating sashes and can be fully opened by unlatching and pushing or using the mechanical window crank for ventilation
Casement
Has two or more sashes of which at least one moves horizontally within the window frame
Horizontal sliding window
In a three sash horizontal sliding window, the middle sash is usually ___
Fixed
Has one or more top-hinged, outward swinging sashes that are opened by unlatching and pushing or using the mechanical window crank
Awning window
The arrangement of an awning window permits the window to be ___
Open during rain
Hopper windows are similar in design to awning windows except they are ___
Hinged at the bottom
Includes a large number of narrow overlapping glass sections swinging outward
Jalousie window
The individual pieces of glass in a jalousie window are about ___
4” wide
The pieces of glass in a jalousie window are supported ___
At the ends by an operating mechanism
Jalousie windows are popular architecturally because ___
The amount of opening can be caried for ventilation without admitting rain
Window that swings outwards at the top or bottom and slides upward or downward in grooves. A push bar that usually operates the projected window is notched to hold the window in place
Projecting window
Window that has a sash that pivots horizontally or vertically on a central axis. Part of the window swings inward and part swings outward when it is opened
Pivoting window
A window of pivoting design provides ___
The full area of the window opening for ventilation
Security is commonly provided for windows, especially those that are ___
Accessible from ground level or adjacent roofs
Common window security method
Fasten metal bars or screens to the exterior of the window frame or to the building itself
The metal bars fastened to the building may be ___
Embedded in masonry or mounted on hinges and locked with padlocks or other locking devices
Security windows are available with movable sashes and fixed bars so that ___
The windows can be opened for ventilation while maintaining the security of the premises
Security bars and grilles must be removed or disabled when interior operations begin to ensure ___
Firefighter safety in case a rapid egress is required
May be used to protect a fire wall opening in an industrial occupancy or an opening in a wall separating buildings into fire areas
Rolling steel shutters
Block interior window openings, such as office windows overlooking a factory floor
Rolling steel shutters
Rolling steel shutters have the same operating components as ___
Rolling steel doors
Rolling steel shutters normally close ___
Under the force of gravity when a fusible link melts, but motor-driven shutters are available
