Transcript FFIIMODB-BC - FVCC Fire Academy

FVCC Fire Rescue
Building Construction
OBJECTIVES
• 2-9.1 Identify the basic structural characteristics
of the following types of building construction:
(3-3.11)





2-9.1.1Fire resistive (Type I)
2-9.1.2
Noncombustible (Type II)
2-9.1.3
Ordinary (Type III)
2-9.1.4
Heavy timber (Type IV)
2-9.1.5
Wood frame (Type V)
OBJECTIVES
• 2-9.2 Identify the two basic types of light wood
framing.
▫ 2-9.1
▫ 2-9.2
Balloon framing
Platform framing
• 2-9.3 Identify the main components of
lightweight framing construction.
▫ 2-9.3.1 Footing
▫ 2-9.3.2 Foundation
OBJECTIVES
▫
▫
▫
▫
▫
▫
▫
▫
2-9.3.3 Plate
2-9.3.4 Stud
2-9.3.5 Joist
2-9.3.6 Rafter
2-9.3.7 Sill
2-9.3.8 Header
2-9.3.9 Ridge Board
2-9.3.10
Eave
OBJECTIVES
▫ 2-9.3.11Fascia
▫ 2-9.3.12
Soffit
▫ 2-9.3.13
Interior finish
 2-9.3.13.1
 2-9.3.13.2
▫ 2-9.3.14
 2-9.3.14.1
 2-9.3.14.2
Plaster
Drywall
Exterior finish
Brick veneer
Sheathing
OBJECTIVES
• 2-9.4
Identify the three, broadly classified,
categories of roofs from a firefighting
standpoint.
▫ 2-9.4.1 Flat roofs
▫ 2-9.4.2 Pitched roofs
▫ 2-9.4.3 Curved roofs
OBJECTIVES
• 2-9.5
Identify structural components of large
structural systems.
▫
▫
▫
▫
▫
2-9.5.1
2-9.5.2
2-9.5.3
2-9.5.4
2-9.5.5
Beams
Columns
Arches
Cables
Trusses
OBJECTIVES
• 2-9.6
Identify the components of truss
construction.
▫ 2-9.6.1 Chords
▫ 2-9.6.2 Web or diagonal members
▫ 2-9.6.3 Gusset plate
• 2-9.7
Identify three hazards associated with
truss and lightweight construction. (3-3.11)
OBJECTIVES
• 2-9.7 Identify dangerous building conditions
created by fire and fire suppression activities. (33.9, 3-3.11)
• 2-9.8 Identify the term “building collapse”. (33.9, 3-3.11)
• 2-9.9 Identify five indicators of building
collapse. (3-3.9, 3-3.11)
OBJECTIVES
• 2-9.11 Identify the effects of fire and fire
suppression activities on the following building
materials. (3-3.9, 3-3.11)








2-9.11.1 Wood
2-9.11.2 Masonry
2-9.11.3 Cast iron
2-9.11.4 Steel
2-9.11.5 Reinforced concrete
2-9.11.6 Gypsum wallboard
2-9.11.7 Glass
2-9.11.8Plaster on lath
OBJECTIVES
• 2-9.11 Identify the following terms as they
relate to building construction: (3-3.11)
▫
▫
▫
▫
▫
▫
▫
2-9.12.1 Load bearing wall
2-9.12.2 Non-load-bearing wall
2-9.12.3 Party wall
2-9.12.4 Fire wall
2-9.12.5 Partition wall
2-9.12.6 Cantilever or unsupported wall
2-9.12.7 Parapet wall
OBJECTIVES
• 2-9.13 Identify the effects of the following
items in a burning building: (3-3.9, 3-3.11)
 2-9.13.1
Intense heat
 2-9.13.2
Dense smoke
 2-9.13.3
Large volume of water pour onto
and into structure
▫ IFSTA, Essentials, 4th ed, Chapter 3
▫ Delmar, Firefighter Handbook, 2000, Chapter 13
BASIC STRUCTURAL CHARACTERISTICS
• Fire Resistive (Type I)
▫ Structural members are noncombustible or
limited combustible materials.
▫ Primary hazard contents.
▫ Ability to confine fire compromised by openings.
A beam being placed on columns. The beams are notched to accept the double Ts.
A double T being lowered into place on the beams
The double Ts are notched to fit onto the beams and
are held in place by their weight.
Flammable liquids from ruptured fuel tanks can
travel to lower levels through penetrations in the
deck.
A parking deck attached to an office building.
Parking decks can be found on top of or below occupied spaces. In this
building, the first several floors of the structure are parking deck topped
with offices.
A stand-alone parking deck.
Stairways in parking decks are often open. Expect
heavy smoke conditions.
HAZARDS OF PRECAST CONCRETE : Slabs are transported to the site and then
lifted into position with a crane. During the construction process, floors are
temporarily connected to the columns. Particular attention must be given to ensure
that the concrete has properly cured before being placed into position and loaded.
Loads need to be constantly monitored during the construction process to prevent
overstressing components. Local failure could trigger a progressive (pancake type)
collapse of all or large parts of the structure.
HAZARDS OF POST-TENSIONING : The weight of the concrete is transferred to
the columns after tensioning. This situation presents a potential for catastrophic
collapse if a column fails. The tendons and anchors used for post-tensioning are left
exposed. They may become heat collectors in a fire. Therefore, it is highly
recommended that anchors be fireproofed immediately after tensioning.
CUTTING THROUGH TENSIONED CONCRETE: Cables embedded in the concrete
are under tension. Cutting a tensioned cable can cause severe injury to the
firefighters as the tension is relieved and damage the concrete with a loss of loadbearing capability. Cutting tensioned cables can lead to a collapse of the structure.
Therefore, do not cut through a concrete parking deck structure. Construction
workers often X-ray the floor before cutting to locate the tensioned cables.
PARKING DECK COLLAPSE
• If the concrete parking deck structure has been rattled, such as in an explosion or
other major impact, it is possible that components may have shifted and may be
prone to collapse. Always evaluate the need to enter parking decks in these
situations. Parking decks may also be in danger of collapse because of improperly
cured concrete or overloading caused by vehicle or ice/snow/rain water
accumulations. Personnel should also be observant for concrete that has been
removed from columns, beams, or the decks themselves, exposing the reinforcing
steel. Concrete may have been removed over time, before the fire, as a result of
having been struck by vehicles. Exposed steel will begin to lose its strength when the
temperature reaches 1,0007F and may be in danger of collapse, depending on the
load carried. As mentioned previously, do not cut through the concrete structures
because of the likelihood of compromising steel reinforcement and possibly causing
injury or collapse.
• Parking decks are becoming more and more common. Preplan these types of
structures in your jurisdiction, and develop the appropriate operating plans and
guidelines.
First interstate Bank Building (Los Angles ) Fire resistive type I construction ( believe it or not!)
Photo by: New York Board of Underwriters
CONCRETE BEHAVIOR IN FIRE
Under fire conditions, concrete resists compressive stresses and yet protects the tensile
strength of the encased steel. Spalling, the failure of the concrete because of entrapped
water's rapid expansion as it turns to steam, may expose the steel reinforcement. Once
the unprotected steel is exposed to fire conditions, collapse may occur rapidly as the
steel loses its ability to carry the load. Concrete absorbs a great amount of heat. In the
short term this is not a problem, but long-term heat exposure complicates firefighting
efforts.
BASIC STRUCTURAL CHARACTERISTICS
• Noncombustible (Type II)
▫ Similar to fire resistive (Type I); only degree of fire
resistance is less.
▫ In some cases, materials with no fire resistance may be
used.
▫ Primary hazard contents
▫ Heat buildup, during a fire, may cause structural
supports to fail.
▫ Type of roof material may contribute to fire extension.
BASIC STRUCTURAL CHARACTERISTICS
• Ordinary (Type III)
▫ Exterior walls and structural members are
noncombustible or limited combustible materials.
▫ Interior structural members completely or partially of
wood.
▫ Wood used has smaller dimensions than Type IV.
▫ Primary hazard is fire and smoke spread through
concealed spaces.
BASIC STRUCTURAL
CHARACTERISTICS
A view of ordinary
construction
from the street.
The same
building. You
can see the
header
courses of
brick by
looking down
the side.
Always look
at as many
sides of the
building as
possible to
determine
construction,
occupancy,
and floor.
Ordinary type III
Construction
Photo by: Warren
Fuchs Brooklyn
Dispatcher
BASIC STRUCTURAL CHARACTERISTICS
• Heavy timber (Type IV)
▫ Exterior and interior walls and associated structural members are
noncombustible or limited combustible materials.
▫ Other interior structural members are made of solid or laminated
wood with no concealed spaces.
▫ Wood has large enough dimensions to be considered heavy
timber.
▫ Primary hazard: the combustible contents of the structural
members.
▫ Because of the amount of heat given off by the structural
members, the building may pose serious exposure protection
problems.
BASIC STRUCTURAL CHARACTERISTICS
• Wood frame (Type V)
▫ All walls and structural supports are made
completely or partially of wood of dimensions less
than heavy timber.
▫ Presents unlimited potential for fire spread.
▫ May present a serious exposure problem
especially if exposures are of similar construction.
The Outer Shell
LIGHT WOOD FRAMING
• Balloon framing
▫ Construction can have open
channels from the foundation to the
attic.
▫ Framing is usually covered with an
interior finish of plaster or drywall.
▫ This balloon-frame structure can
easily be recognized by the roofline
façade. Because of the fire escapes
on the “B” side , anticipate that
there are front and rear
apartments on each floor where
there should be only one large unit.
The floor plan will also be different
from what you would normally
find.
Wait until we get to
void spaces
The building industry calls these cross braces firestopping. In fact, their purpose is to
brace the stud (which is a column receiving compressive loads) at about midpoint, thus
greatly increasing its load-carrying capacity. Their firestopping value is incidentalfirestopping should cut off the wall voids from the floor voids.
LIGHT WOOD FRAMING
• Platform framing
▫ Construction has each floor constructed on its own
platform, reducing open channels in the wall.
▫ Framing is usually covered with an interior finish
of plaster or drywall.
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Footing: That part of the building that rests on
the bearing soil and is wider than the foundation
wall. Also the base for a column. It spreads the
weight of a wall or column and presents settling.
• Foundation: The supporting part of a wall
usually of masonry or concrete and at least
partially underground.
Foundation Footings
Stepped footing can support a concrete block wall. Blocks have nominal
dimensions of 8 by 8 by 16 inches (the actual dimensions are actually 3/8
inch smaller than these to allow for mortar joints). They are hollow when
laid-up; steel reinforcing bar called rebar is added and the hollows in the
blocks are often filled with concrete. They lend themselves to construction
where forming concrete is difficult or impractical.
Concrete blocks are also used for standard foundation wall construction.
Here they are supported by a concrete footing; both are reinforced with
steel rods and the concrete blocks are filled with grout.
A concrete pier, resting on a footing, may be used to help support beams
at mid-span. Though some older homes rest entirely on piers, this method
has been phased out in favor of stronger foundations.
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Plate:
The top or bottom horizontal structural
member of a frame wall or partition.
• Stud:
Vertical structural uprights which
make up the walls and partitions in a frame
building.
• Joist:
A framing member which directly
supports the floor.
(9) This is a "flitch plate girder," a piece of steel plate sandwiched between two wood beams. It tells
us that the beam is carrying an unusually heavy load or long span. If the wood burns, the steel will
buckle and the beam will fail. Note this hazard on the preplan.
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Sill: The bottom rough structural
member that rests on the foundation or
the bottom exterior member of a window
or door or other masonry below.
• Head: The top of a window or
doorframe.
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Ridge Board: The horizontal timber or beam at
the ridge of a roof, to which the upper ends of
the rafters are attached. (Next Slide)
• Eave: The lower edge of a roof, usually
projecting beyond the sides of a building.
• Rafter: A beam that supports a roof. (next slide)
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Cornice: A horizontal projection that crowns or
finishes the eave of a building.
• Fascia: A flat vertical board located at the outer
face of a cornice.
• Soffit: A lower horizontal surface such as the
undersurface of eaves or cornice.
Fascia and Soffit
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Interior finish
▫ Plaster: A fire-resistive cement material that is
applied over lathing, which is either a wire mesh
or a gypsum board with a fibrous paper.
▫ Drywall:
A system of interior wall finish
using sheets of gypsum board and taped joints.
LIGHTWEIGHT FRAMING
CONSTRUCTION
• Exterior finish
▫ Brick veneer: Single thickness of brick wall facing
placed over frame construction or masonry other
than brick.
▫ Sheathing:
Covering applied to the
framing of a building to which siding is applied.
Brick veneer
The brick
wall is
connected
to the
wooden
wall by
thin steel
tabs
nailed to
the wall.
This makes brick masonry and veneer brick walls look alike. Know your buildings.
Recently, a Dallas, Texas, firefighter was killed in the collapse of a brick wall of a building
that was being renovated. When in doubt, consider the wall to be brick veneer.
Click here to enlarge image
Notice the brick veneer on the front of this platform-frame, single-family house. On the
left side of the first floor, firefighters can expect to find a vaulted ceiling and must be
cautious to ensure that the fire is not rolling over their heads. As they move deeper into
the building, they should check it with a pike pole or a quick shot of water.
This new lightweight frame construction is located in the rehab zone. The front is brick
veneer; the sides are vinyl. It most likely was built with truss floor and roof supports.
Check it at the door before moving in too far.
ROOFS
• Flat roofs
• Pitched roofs
▫
▫
▫
▫
▫
▫
▫
▫
Gable roofs
Hip roofs
Gambrel roofs
Mansard roofs
Shed roofs
Butterfly roofs
Monitor roofs
Saw tooth roofs
• Curved roofs
LARGE STRUCTURAL SYSTEMS
• Beams:
A structural member subjected to loads
perpendicular to its length.
• Columns: A vertical supporting member.
• Arches: Curved structural member in which the
interior stresses are primarily compressive. Arches
develop inclined reactions at their support.
• Cables:
Flexible structural members in which the
stresses in the cable are tension stresses.
• Trusses: Framed structural units made of a group of
triangles in one plane.
TRUSS CONSTRUCTION
• Chords: Top and bottom horizontal members of
a truss.
• Web or diagonal members: Vertical members
between the chords.
• Gusset plate: Plate that is used to connect the
members of a wood or metal truss.
Photo R275 - The bottom chord of this truss is under a tensile (pulling) load when in place.
It consists of three pieces of wood with four gusset plate connectors. When the gusset plate heats
up, the heat is transferred to the teeth by conduction. The heated teeth destroy the wood fibers in
tension which were gripping the teeth. It is called pyrolytic decomposition, burning without flame
as occurs when you burn the company number into an axe handle.
Photo R244 - This construction illustrates the value of trusses.
To build a conventional building this wide would have required
heavy roof beams or bothersome interior columns.The walls
would need to be much heavier to carry the weight of the long
rafters.The truss provides clear spans at low cost. Know your
buildings and use the thermal imager (Firefighter’s Radar) to
detect hidden fire.
HAZARDS ASSOCIATED WITH TRUSS &
LIGHTWEIGHT CONSTRUCTION
• Designed to support only own weight
• If one fails, a domino effect usually occurs until
total collapse has resulted.
• Rapid failure under fire conditions:
▫ Usually 5 to 10 minutes
▫ Wood – ¼ inch char
▫ Steel 1000 degree F.
(5) In some cases, an unprotected steel beam or a flitch plate girder (see photo 9) is used to
provide a wide, clear span. The failure of a steel beam cost the life of a Georgia firefighter.
(6) The peaked roof is supported on lightweight wood trusses. Personnel operating from a tower
ladder should perform ventilation. No code requires that the roof be a safe operating platform for
firefighters
DANGEROUS CONDITIONS CREATED BY FIRE
& FIRE SUPRESSION
• Two primary types of dangerous conditions.
 Conditions that contribute to the spread and
intensity of the fire.
 Conditions that make the building susceptible to
collapse.
DANGEROUS CONDITIONS CREATED BY FIRE
& FIRE SUPRESSION
• Conditions that contribute to the spread and
intensity of the fire.
▫ Fire loading
 Presence of large amounts of combustible materials in an area
of a building.
 Arrangement of combustible materials in a building.
▫ Combustible furnishings and finishes
▫ Roof coverings
▫ Wooden floors and ceilings
Patrons attempted to leave by the hallway to the club's front door, but the exit there
soon grew choked. Most of the crowd apparently attempted to leave through that
exit, fire officials said.
The rush to exit the front left a pile of people, trapped in the burning building. Fire
officials estimated the number of people inside as less than 300, the club's official
capacity.
Rescuers attempted to pull people from the front door pile.
According to authorities, most of the bodies later found were near
the front door.
Within minutes, the building was in flames. Firefighters fought the
blaze in vain but were able to rescue some people inside.
DANGEROUS CONDITIONS CREATED BY FIRE
& FIRE SUPRESSION
▫
▫
▫
▫
Large open spaces
Building collapse
Lightweight and truss construction
Construction, renovation and demolition
• A trained eye would detect that this Suburban
Hospital Bethesda MD Outpatient Center is a post
tensioned concrete construction job and all that
dry hard concrete is not attached to the building
and is supported only by the fire vulnerable
wooden falsework Smoke might obscure vision so
the only sound precaution is for the FD to be
aware on a daily basis of this deadly type of
construction.
Note the wood stud bearing wall against the concrete block firewall. The code
applicable to this building permits no penetration of the firewall. Other codes
permit the firewall to be used structurally, thus providing fire penetrations. Know
your buildings! (BCFS3, 234)
Void Spaces
Heavy wood firestopping was removed to install a standpipe main requested by the fire
department. The Fire Department of New York, which developed standpipe operations, finds it
is faster to stretch directly to the third floor instead of using the standpipe Here, the
firestopping was not replaced because the gypsum board ceiling was installed right after I
took this picture. A void fire would spread throughout the voids, following the fire main.
Fire would spread from floor to floor through the piping holes. The collapse hazard may drive
firefighters from the building, especially if the floors are of truss construction. You did not lose the
building—the construction techniques used, which made it deadly for firefighters to remain in the
building, destroyed it. It is a combustible building, a type that can be destroyed easily by fire.
4) Wooden I-beams are no better than trusses as fire stops
because they legally can have holes for wiring and large holes
for ducts, metal, or plastic.
For economy, apartment kitchens are built back-to-back. If the connection is not
adequately firestopped (practically impossible), expect early extension of a kitchen fire to
the next unit.
A fire in one kitchen will be in the next kitchen by the time you arrive. Chapter 5 of
BCFS3 contains a full discussion of the deficiencies in fire containment in garden
apartments and similar commercial structures.
This flat roof attic space, or cockloft, goes from side to side and from the front to the
back of this building. When the fire reaches the cockloft space, it will spread horizontally
along the direction of the roof joists
This lightweight truss loft will allow fire to spread horizontally similar to the
way it would in a cockloft; however, a cockloft is built with 2-inch 2 12-inch
wood, whereas this fire will spread along and through the trusses. Because
of the fire spread and the members' low mass, the members will fail within
five to 10 minutes.
Roof Coverings
BUILDING COLLAPSE
• Resulting from damage to the structural system
of the building caused by the fire or by
firefighting operations.
• Most likely time when firefighters are killed or
injured.
• Most likely time when R.I.T. is put into action.
• When Building Collapse is evident or possible,
operations should be made from the corners of
the buildings!!
April 2004 Ebenezer
Baptist
Church Pittsburgh, PA
Collapse Zone
• 1 ½ times the
height of the
building.
INDICATORS OF BUILDING COLLAPSE
• Cracks or separations in walls, floors, ceilings
and roof structures.
• Evidence of existing structural instability such as
the presence of tie rods.
• Stairs that hold the wall together
• Loose bricks, blocks or stones falling from the
building
• Deteriorated mortar between the masonry.
• Walls that appear to be leaning in one direction
or another
Collapsing floor joists can pull down a masonry wall. The so-called fire cut (cutting the
end of the joist off at an angle) was developed to prevent any leverage on the wall.
(BCFS3, 166)
INDICATORS OF BUILDING COLLAPSE
• Are there any of these signs on buildings in your
town?
• Bet you there are!
INDICATORS OF BUILDING COLLAPSE
• Structural members that appear to be distorted
or pulling away from the walls
• Fires beneath floors that support heavy
machinery or other extreme weight loads.
• Prolonged fire exposure to the structural
members.
• Unusual creaks and cracking noises.
EFFECTS OF FIRE & FIRE SUPPRESSION
• Wood – reaction depends on size of the wood
component. (The smaller the size, the more
likely to lose integrity Type IV Construction v.
Type V Construction)
▫ Moisture content of wood (old v. new)
▫ Application of water has no adverse impact on
(11) Lightweight floor construction will not withstand more than a few minutes of fire
exposure and cannot support a company advancing through the front door. A basement fire
may have to be attacked from a window or an outside entrance. (Photo by Lazaro Acosta.)
This beam is made up of planks glued
together. The industry calls this
"engineered wood"; all wood products
that are not simply sawn from a log
could be called "engineered wood."
The industry brags that this wood only
chars un-der fire conditions that
would cause a steel beam to fail; it
neglects to mention that many,
possibly most, of the beams are
supported on unprotected steel
columns and are often connected with
steel ties.
Laminated beams can be formed in shapes such as these curves. A fire
spreading across this polished ceiling is best fought by smooth-bore streams
that can reach the ceiling and, so to speak, "fireproof" the wood.
Commonly found in churches, these laminated
timbers are formed into arches or rigid frames.
Such arches are most often tied together foot to
foot with steel rods. If the church is built on a
slab, the rods are buried in the slab. If there is a
basement, the rods may be ex-posed to a
basement fire, causing them to weaken or
come loose, and the arches are likely to
collapse. (BCFS3, 74-78)
Plywood delaminates. The layers
come apart, thus the burning surface
area and the intensity of the fire are
increased. (BCFS3, 114)
This is oriented strand board (OSB),
chips of wood glued together. If
someone were to burn comparable
strips of OSB and conventional
plywood to determine if there is a
significant difference in burning
characteristics, I would be happy to
hear of the results.
This is chipboard, which has been used for flooring in some trailers. A St. Mary's
County, Maryland, firefighter went through the floor as the water-soaked chipboard
collapsed. This loaded sample collapsed in a couple of minutes
EFFECTS OF FIRE & FIRE SUPPRESSION
• Masonry
▫ Minimally affected by fire (heat).
▫ Mortar between masonry components subject to more
deterioration and weakening from fire.
▫ Rapid cooling may cause some masonry components
such as bricks, blocks or stone to spall.
▫ Masonry components should be inspected after
extinguishment to determine signs of damage.
EFFECTS OF FIRE & FIRE SUPPRESSION
• Cast Iron
▫ Found only in older buildings.
▫ Bolts and other fastening devices may fail when
exposed to fire, permitting large sections of cast iron
walls to fall.
• Steel
▫ Members elongate when heated (50 ft beam may
elongate 4 inches when heated to 1000 degrees F.
▫ If ends are restrained, it will buckle or fail somewhere
in the middle.
▫ Failure can be anticipated at 1000 degrees F.
These gas lines in a garden apartment basement are poorly attached to the structure. A
fire caused the line supports to fail. Fortunately, the firefighters were on the escape side
of the pipes, which dropped to the floor and ruptured, releasing gas to intensify the fire.
(BCFS3, 222-223)
EFFECTS OF FIRE & FIRE SUPPRESSION
• Reinforced concrete
▫ Loses strength and spalls.
▫ Heat may cause failure of bond between concrete and
steel reinforcement.
• Gypsum wallboard
▫ Excellent heat-resistant and fire-retardant properties.
▫ Will gradually break down under fire conditions.
▫ Members protected by gypsum could be exposed to
high temperatures if gypsum fails.
EFFECTS OF FIRE & FIRE SUPPRESSION
• Glass/fiberglass
▫ Glass does not contribute to the fire load, but
resins used in fiberglass will.
▫ Heated glass may crack when hit by a fire stream.
• Plaster on lath
▫ Similar to gypsum
▫ Large sections may fall during firefighting
operations.
TERMS
• Load-bearing wall: walls that support structural
weight
• Non-load-bearing wall: walls that do not support
structural weight.
• Party wall: load-bearing wall that supports two
adjacent structures
Load-Bearing Walls
Exterior walls that carry ceiling, roof or upper floor loads to the foundation are load bearing or "bearing" walls. Internal walls that support joists at mid span
and transfer loads down to foundations are also bearing walls. Bearing walls usually have perpendicular joists or rafters crossing or resting on top of them and
foundations underneath them. An exception are the end walls of a gable-roofed house; these usually run parallel to rafters and joists but must bear the weight
of extensive wall framing.
Wind and seismic loads, which produce lateral stresses on a house, are managed by tightly interlocking framing members. Plywood sheathing or wood or metal
crossbracing interconnect framing members, creating a sturdy triangular form and-together with foundation bolts-lock walls to foundation. The roof is
protected from wind uplift by steel strapping.
TERMS
• Fire wall: separates two structures,
or divides a structure into smaller
portions to prevent the spread of
fire.
• Partition wall: non-load-bearing
wall that divides two areas within
a structure.
• Cantilever or unsupported wall:
freestanding firewall usually found
in shopping centers or churches.
• Parapet wall: low wall at the edge
of a roof.
EFFECTS IN A BURNING BUILDING
• Intense heat
▫ Causes access problems to firefighters during
operations
▫ Contributes to fire spread
• Dense smoke
▫ Hampers firefighting operations
▫ Proper ventilation is required to ensure:
 Removal of smoke
 Stability of building
EFFECTS IN A BURNING BUILDING
• Large volume of water poured
into and on the structure
▫ Compromises integrity of
construction materials
▫ Accumulation of water on the
upper floors or roof will add to
the live load of an already
weakened structure.
Homework
Match Roman numeral building construction types
to their basic structural characteristics. Write the
correct letters on the blanks.
1.
2.
3.
4.
5.
a.
b.
c.
d.
e.
__
__
__
__
__
Wood frame construction
Non-combustible or limited combustible construction
Ordinary construction
Heavy timber construction
Fire-resistive construction
Type I
Type II
Type III
Type IV
Type V
Homework
______ 6.Exterior walls and structural members of noncombustible or limited
combustible materials; interior members completely or partially of small-dimension
wood; associated fire hazards reduced by placement of fire stops inside concealed
spaces
______ 7. Construction intended to confine fire and its by-products to a given location;
structural members made of noncombustible or limited combustible materials
______ 8.Exterior and interior structural members made completely or partially of
small-dimension wood and other materials
______ 9.Exterior and interior walls and structural members of noncombustible or
limited combustible materials; other interior structural members of solid or laminated
wood with no concealed spaces; used in old construction of factories, mills, and
warehouses
______ 10.Lower degree of fire resistance than fire- resistive construction; flat, builtup roofs common feature of this type of construction
a. Type I
e. Type V
b. Type II
c. Type III
d. Type IV
Homework
____ 11. Almost unlimited potential for fire extension within structure; fire
extension to other structures; fire extension from doors and windows to
exterior of structure
____ 12. Smoke and fire spread through concealed spaces
____ 13. Contents of structure
____ 14. Massive amount of combustible structural and building contents;
exposure protection problems caused by structural members giving off
tremendous heat
____ 15. Contents of structure; failure of structural supports; failure of flat,
built-up roofs often used in this type of construction.
a.
Wood-frame construction
b.
Noncombustible or limited combustible construction
c.
Ordinary construction
d.
Heavy timber construction
e.
Fire-resistive construction
Homework
16. ____ Wall that supports structural weight
17. ____ Load-bearing wall that supports two adjacent
structures
18. ____ Non- load-bearing wall that divides two areas
within a structure
19. ____ Wall that does not support structural weight
a) Non Load Bearing Wall
b) Partition Wall
c) Party Wall
d) Load Bearing Wall
Homework
20. ____ Decorative wall; usually attached to
the outside of some load-bearing frame or
structure
21. ____ Load-bearing wall that separates two
connected structures
22. ____ Free standing wall commonly found
on large churches and shopping centers.
A) Cantilever Wall
B) Veneer Wall
C) Fire Wall
Homework
23. ____ Is the presence of large amounts of combustible materials
24. ____ is one of the most critical hazards in commercial and
storage facilities
25. ____ Toxic gages produced by burning furnishings and
finishes are major factors in the loss of many lives in fires.
26. ____ Combustibility of covering is a concern to entire
community; flaming embers fly from roof to roof easily
27. ____ even when treated with fire retardant, significantly
contribute to fire spread
a) Combustible Furnishings/ Finishes b) Fireloading
c) Heavy Content Fireloading
d) Roof Coverings
e) Wood Shake Shingles
Homework
28. ____ Encountered most often in residential construction
29. ____ Members fail after only 5 to 10 minutes
30. ____ Are common in warehouses, churches, large atriums, common
attics, and theaters
31. ____ Is common construction method in houses, apartments, and
small commercial buildings
32. ____ Proper vertical ventilation is essential
33. ____ Crews should not go onto the roof after these buildings have
been exposed to fire conditions
Using answers more than one time, match the correct answer to the
building characteristic described above.
a) Large Open Spaces b) Lightweight & Truss Construction
c) Wooden Frames/ Floors/ Ceilings
Homework
34. ___ Includes additional fire load and ignition sources
35. ___ Cracks or separations in walls, floors, ceilings, and roof structures
36. ___ Disabled fire protection systems create potential problems
37. ___ Evidence of existing structural instability
38. ___ Loose bricks, blocks, or stones
Using answers more than one time, match the correct answer to the building
characteristic described above
a)
Construction hazards b) Renovation/demolition hazards
c) Potential Building Collapse
Homework
39. ___ Unusual creaks and cracking noises
40. ___ Does not have protective features in place yet
41. ___ Structural members pulling away from walls
42. ___ Easy access into building creates arson factor
43. ___ Excessive weight of building contents
Using answers more than one time, match the correct answer to the
building characteristic described above
a)
Construction hazards b) Renovation/demolition hazards
c) Potential Building Collapse
Homework
44. ___ Are typically found only on older
buildings; rarely used in modern construction
45. ___ Large pieces of wood retain much of their
original integrity even after extensive fire
exposure
46. ___ Will spall or crack if rapidly cooled with
fire streams
47. ___ May elongate a 50-foot beam by as much
as 4 inches when heated to about 1,000°F
a) Cast Iron b) Masonry c) Steel d) wood
Homework
48. ___ The smaller the size, the more likely it is to lose its
structural integrity; smaller pieces may be protected by drywall
or gypsum to increase their fire resistance
49. ___ The mortar between masonry materials may deteriorate
and should be checked for signs of weakening
50. ___ Elongate when heated and can push out load-bearing
walls
51. ___ Include fasteners that hold veneer to building; these fail
first, causing large, heavy veneer sections to fall
a) Cast Iron b) Masonry c) Steel d) wood
Homework
52. ___ Chance of collapse is reduced when
steel is cooled with water.
53. ___ Impregnated with fire retardants does
not ignite or burn as fast as untreated.
54. ___ May crack but usually retain most of
their strength
55. ___ Stand up well to fire and intense heat
a) Cast Iron b) Masonry c) Steel d) wood
Homework
56. ___ Are generally fastened to building fronts as veneer walls
57. ___ Rarely show signs of loss of integrity or deterioration
other types may spall or lose small portions of their surface
58. ___ Water applied during fire suppression activities has no
significant negative effect.
59. ___ Temperature at which a the member will fail depends on
many variables such as: Size, Load, Composition and Geometry
a) Cast Iron b) Masonry c) Steel d) wood
Homework
60. ___ May be wire-reinforced, which provides
some thermal protection, but are not an
effective barrier to fire extension.
61. ___ Have high water content, the evaporation
of which takes a good deal of heat
62. ___ Lose their strength and crack and spall
under fire conditions
a) Gypsum
b) Fiberglass/ Glass
c) Reinforced Concrete
Homework
63. ___ Gradually break down under fire conditions,
exposing the members behind it to higher
temperatures and possible failure
64. ___ May separate from reinforcement material
when heat causes the bond between the two to fail
65. ___ When heated, may crack when struck by a cold
fire stream
a) Gypsum
b) Fiberglass/ Glass
c) Reinforced Concrete