two or more interconnected structural components combined to meet a specific function or design requirement.
typically they are roof trusses, wall frames, and doors w/frames
Define an attic.
an open space between the rood and ceiling of a building
most commonly found in single and multi family residential occupancies.
provides open spaces in which fire can burn undetected or spread throughout a structure
What is a balloon frame?
type of wood-frame construction in which the studs in the exterior walls extend from the basement or foundation to the roof
this type of construction allows fires to spread - often undetected - from the basement to the attic through the hollow walls
What is a bar joist?
a joist constructed of steel with bars in the vertical web space
common structural component in office buildings and other commercial structures
very high strength to weight ration except when exposed to heat or fire - then early failure in likely
Define a beam
horizontal structure component subjected to vertical loads
typical beams are steel or wooden I-beams or large-dimension wooden members
What is a bowstring truss?
a roof assembly with curved (arched) top chords and a horizontal bottom chord
very strong except when exposed to direct flame contact when catastrophic failure without warning may occur
What is a butterfly roof?
v-shaped roof in which the two sides slope toward a valley in the middle
rare, especially in climates where snow load is a factor
What is a cantilever?
a beam that is unsupported at one or both ends
typically used to support balconies on apartments and some office buildings
Define a chord.
main structural members of a truss
span the open space between the upper and lower diagonal members in a truss assembly
What is a cockloft?
an open space between the roof and ceiling of a commercial or industrial building
usually found under flat or nearly flat roofs
in a fire, these spaces act much like attics
What is a column?
vertical supporting member
may be wooden or steel posts
steel posts often support lightweight roof assemblies
if unprotected by surface insulation, steel posts may fail quickly in fire
What is compression?
force that tends to push the mass of a material together
bearing walls in a building are under compression from the weight of the roof and other materials above
What is a course?
horizontal layer of masonry units
bricks are example of a course
What is a curtain board?
nonload-bearing interior wall extending down from a roof or ceiling to limit the horizontal spread of fire/heat
What is a curtain wall?
nonload-bearing exterior wall used as a weather barrier but not for structural support
on many high rise buildings
outside walls (often sheet glass in frames) are curtain walls
What is decking?
planks or panels of plywood or oriented strand board (OSB) that form the substrate of a roof assembly
must be removed during vertical ventilation
What is drywall?
gypsum wall board
aka sheetrock
fire resistive
What is an eave?
the outside edge of a pitched roof that overhangs an outside wall
attic vents an typical eaves provide good avenue for an exterior fire to enter the attic
What is an engineered I-beam?
a wooden I-beam consisting of continuous wooden upper and lower chords separated by a web of OSB or similar sheet stock
What is a fire door?
a rated assembly consisting of a sold-core door, door frame, and hardware.
used to confine a fire to one room or section of building
in order function properly, they must not be blocked open - intentionally or not
What is a fire load?
total potential heat release if a building and its contents burned
fire load in a lumber yard is much higher than that of an empty building with the same dimensions
What is a fire wall?
a rated assembly that extends from the foundation to and through the roof of a building to limit fire spread
intended to confine fire to one room or section of building
What is a flat roof?
a roof that is flat or nearly flat relative to the horizon
many commercial buildings have flat roofs covered with tar and gravel or other weatherproof material
lend themselves to easy ventilation
What is a gable roof?
a pitched roof characterized by square-cut ends and sides that slope down from the ridge line to the eaves
common in homes and small buildings (like an A frame house, standard roof for houses)
What is a gambrel roof?
a roof characterized by a single ridge line from which rood sections on both sides of the ridge descend at two different pitches (think barn)
can make roof ladders difficult to use
What is a girder?
horizontal structural member used to support beams or joists
almost always of larger dimensions that the members they support
What is a glue-lam beam?
wooden structural member composed of relatively short pieces of lumber glued and laminated together under pressure to forma long, extremely strong beam
very fire resistive
What is a gusset plate?
wooden or metal plate used to connect structural members that are buttered together
most often used in the construction of trusses
can be subject to early failure if the plates warp from heat
plates that are nailed/screwed are much more reliable during fire
What is gypsum board?
interior finish material consisting of calcinated gypsum, starch, water and other additives sandwiched between two sheets of specially treated paper
AKA - drywall
What is a header course?
course of bricks laid with the ends facing outward
only used in unreinforced masonry, making it easy to identify
What is a hip roof?
pitched roof in which ends are all beveled so that there are no gable walls
common in new construction
attic vents are only under eaves or on roof
What is HVAC?
abbreviation for heating, ventilating, and air conditioning
ductwork associated with HVAC can allow smoke and fire to spread throughout buildings, unless properly protected with automatic fire dampers
What is interstitial space?
an accessible or inaccessible space between layers of building materials
can be an attic or cockloft used to house HVAC and other machinery
unless properly protected, can allow fire to burn undetected or to spread throughout a building
What are joists?
horizontal structural members used to support a ceiling or floor
drywall materials are nailed or screwed to ceiling joists and subfloor is nailed or screwed to floor joists
What is a lamella arch?
arch constructed of short wooden members connected in a specific geometric pattern
rare in new construction, mainly in older buildings
What is a mansard roof?
rood characterized by steeply sloped facets surrounding a flat or nearly flat center section
many remodeled buildings have false mansard roofs
What is mortar?
mixture of sand, cement, and water used to bond masonry units into solid mass
mortar joints are easiest to penetrate when a masonry wall must be breached
What is an open web joist?
joist constructed of a web composed of materials such as bars or tubes that do not fill the entire web space
very common b/c they're cheap
loos strength quickly in fire
What is Oriented Strand Board (OSB)?
a wooden structual panel formed by gluing and compressing wood strands together under pressure
roof decks, walls, subfloors all commonly made of OSB
What is a parallel chord truss?
truss constructed with the top and bottom chords parallel
used as floor joists in multistory buildings and as ceiling joists in buildings with flat roofs
What is a parapet?
a wall at the edge of some roofs
range from a few inches to a few feet in height
What is a party wall?
wall shared by two adjoining buildings
usually load bearing wall that is also a fire wall
What is pitch?
the ratio of rise to span of a roof assembly
steeper pitch = greater slip hazard
What is a pitched roof?
roof that is sloped to facilitate run-off
What is a plate?
top or bottom horizontal member of a frame wall
sole plate is nailed or screwed to the subfloor and top plate is what the roof assembly rests on
What is platform construction?
frame-type construction in which each floor interrupts the exterior studs forming an effective fire-stop and every floor
most common type of construction used to frame modern homes and small buildings
What is plywood?
wooden structural panel formed by gluing and laminating very thin sheets of wood together under pressure
mostly been replaced by OSB
What are rafters?
beams that span from a ridge board to an exterior wall plate to support roof decking
avoid cutting rafters during vertical ventilation to avoid weakening the roof
What is a rated assembly?
two or more construction components combined to form an assembly that has a specific fire-resistance rating
fire door is an example of rated assembly
What is rebar?
short for reinforcing bar
steel bars places in concrete forms before cement is poured
adds considerable strength to concrete
What is reinforced concrete?
concrete that has been poured into forms that contain an interconnected network of steel rebar
What is a sawtooth roof?
a roof with a profile of vertical and sloping surfaces that resemble a saw blade
common in older buildings
vertical walls usually have many windows and can often be opened to provide natural/adequate ventilation during a fire
What is sheathing?
aka - sheeting
plywood osb, or wooden planking applied to a wall or roof over which a weather-resistive covering is applied
What is a shed roof?
pitched roof that slopes in one direction only form the ridge
What is spalling?
degradation of concrete due to prolonged exposure to high heat
water trapped within the concrete is vaporizes by the heat and expands, causing the concrete to break apart
can sound like gunfire
What is a stud?
vertical structural member in a frame wall
can be made of wood or light-gauge steel
stud walls are the assemblies to which wall coverings are nailed or screwed
What is tension?
force that tends to pull the mass of material apart
tension is what caused some roof assemblies to pull away from walls and fall inward
What is a truss?
a wooden or metal structural unit made up of one or more triangles in a flat plane
What is a load-bearing wall
a wall that is used for structural support
What is a nonload-bearing wall?
wall, usually interior, that supports only its own weight
What is a partition wall?
interior non-load bearing wall that separates a space into rooms
What is green wood?
wood high in moisture content
What are veneer walls?
walls with a surface layer of attractive material laid over a base of common material
brick that shows just on the exterior is an example of veneer walls
What are the 7 common building materials?
wood
masonry
cast iron
steel
reinforced concrete
gypsum
glass/fiberglass
What is the most common building material used in North America?
wood
Because _____ does not burn, it is used in the construction of fire walls.
masonry
What building material can crack or shatter when rapidly cooled with water, causing failure and large heavy structures of metal to come crashing down?
cast iron
What is the primary material used for structural support in the construction of large modern buildings?
steel
A 50-foot steel beam may elongate as much as ___ when heated from room temperature to about 1,000 degrees F.
4 inches
True or False: The glass component of fiberglass and the material used to bind the fiberglass are both fire resistive.
False - glass is not a significant fuel, but the materials used to bind fiberglass may be combustable
What is type I construction?
fire-resistive
construction that maintains its structural integrity during a fire
What is type II construction?
noncombustible construction
construction made of the same materials as fire-resistive construction expect that the structural components lack the insulation or other protection of type I
What are the benefits of type I construction?
resists direct flame impingment
confines fire well
little collapse potential from effects of fire alone
impervious to water damage
What are the weaknesses of type I construction?
difficult to breach for access or escape
difficult to ventilate during fire
massive debris following collapse
floors, ceilings, and walls retain heat
What are the strengths of type II construction?
almost as fire resistive as type I
confines fire well
almost as structurally stable as type I
easier to ventilate than type I
What are the weaknesses of type II construction?
difficult to breach from access or escape
unprotected steel structural components can fail due to heat
steel components subject to weakening by fire, rust and corrosion
massive debris following collapse
What is type III construction?
ordinary construction
requires that exterior walls and structural members be made of noncombustible or limited combustible materials
What are the strengths of type III construction?
resists fire spread from the outside
relatively easy to vertically ventilate
What are the weaknesses of type III construction?
interior structural members vulnerable to fire involvement
fire spread potential through concealed spaces
susceptible to water damage
What is type IV construction?
heavy timber construction
What are the strengths of type IV construction?
resists collapse due to flame impingement of heavy beams
structurally stable
relatively easy to vertically or horizontally ventilate
relatively easy to breach for access or escape
manageable debris following collapse
What are the weaknesses of type IV construction?
susceptible to fire spread from outside
potential for flame spread to other nearby structures
susceptible to rapid interior flame spread
susceptible to water damage
What is type V construction?
wood-frame construction
has exterior walls, bearing walls, floors, roofs, and support made completely or partially of wood or other approved materials of smaller dimensions than used for heavy timber construction
What are the strengths of type V construction?
easily breached for access, ventilation, or escape
resistant to collapse from earthquakes due to light weight and flexibility
collapse debris relatively easy to manage
What are the weaknesses of type V construction?
susceptible to fire spread from outside and rapid flame spread inside
susceptible to total collapse due to fire or explosion
susceptible to water damage
When sizing up a building, you should look for...
age of building
construction materials
roof type
renovations or modifications
dead loads
What is heavy fire loading?
presence of large amounts of combustible materials in an area or building
What is the collapse zone?
the area extending horizontally from the base of the wall to one and one-half times the height of the wall
