Transcript BUILDING CONSTRUCTION IFSTA : Chapter 3 1

BUILDING CONSTRUCTION
IFSTA : Chapter 3
1
BUILDING CONSTRUCTION
IFSTA : Chapter 3
• Additional reading:
– IFSTA Essentials #4 – chapter 8, 9, 10
• Only for the information relating to building
construction
• Some quiz, midterm and final questions will
be from this material
2
Learning Objectives
• List and define five types of building construction.
• Identify the effects fire has on common building
materials to enable firefighter’s to effectively
attack the fire.
• Identify the different occupancies and their effects
at a structure fire.
3
Learning Objectives
• Identify the hazards of building construction
during fire suppression operations.
• Identify construction features during size up.
• Identify indicators of structural failure or collapse
during fire suppression operations
4
Types of Building Construction
• Most building codes have 5 types of
building construction.
• Many buildings include several types of
construction.
5
Type I: Fire Resistive
Construction
• Structural members made
of noncombustible /
limited combustible
materials.
• Construction intended to
confine fire and its
byproducts to a given
location.
• Primary fire hazard is
contents of structure.
6
Type II: Noncombustible
Construction
• Lower degree of fire resistance
than type I.
• Fire resistance rating on all
exterior and interior load
bearing walls.
• May have combustible features,
as materials with no fire
resistance rating may be used.
• Generally have flat roofs with
combustible felt, insulation and
roofing tar.
7
Why is Size-up Important?
8
Type III: Ordinary Construction
• Exterior walls & structural
members of
noncombustible / limited
combustible materials.
• Interior members (walls,
beams, floors, roof) are
made of wood.
• Hazards: smoke and fire
spread through concealed
spaces.
• Fire stops to limit spread.
9
Type IV: Heavy Timber
• Exterior / interior walls
noncombustible material.
• Interior structural members
(beams, columns, arches,
floors etc.) made of solid or
laminated wood with no
concealed spaces.
• Found in old factories,
warehouses, churches.
10
Type V: Frame Construction
11
Type V: Frame Construction
• Exterior and interior structural members
made of wood.
• Fire Hazards: unlimited potential for fire
extension, fire extension to nearby
structures.
• Typical residential home
12
13
Platform Frame
14
“Silent Flooring”
15
Poor Construction Methods
16
Fire Effects on Common
Construction Materials – Wood
• May be used in load bearing and non-load bearing
walls.
• Reaction of wood to fire conditions is based on the
size of the wood and its moisture content.
• Water does not have a negative effect on wood’s
structural strength.
• Plywood, particle board, paneling may be highly
combustible, produce toxic gases and rapidly
deteriorate under fire conditions.
17
Fire Effects on Common
Construction Materials - Masonry
• Brick, concrete, and stonework.
• Commonly used for firewalls to separate connected
structures and prevent fire spread.
• May be used as load bearing or veneer.
• Minimally affected by fire & high temperatures.
• Mortar joints between bricks, blocks may
deteriorate. (mortar mix is weakest part of wall)
• Rapid cooling of masonry by water may cause
cracking or spalling.
18
19
Fire Effects on Common
Construction Materials - Concrete
• Concrete is a mixture of portland cement, sand,
gravel and water.
• Often used as a fire resistive protection for
structural steel (reinforced concrete).
• May crack or spall if heated, indication of damage
& reduced strength.
• Heating may cause bond between steel and
concrete to fail.
• Concrete tends to absorb and retain heat.
20
Fire Effects on Common
Construction Materials –
Reinforced Concrete
21
Fire Effects on Common
Construction Materials - Steel
• Primary use of steel is for structural
members.
• Steel is an excellent conductor of heat.
• Steel loses strength as temperature increases
• Steel structural members will elongate when
heated.
• Water can cool steel structural members and
reduce risk of failure or collapse.
22
Fire Effects on Common
Construction Materials - Steel
23
Fire Effects on Common
Construction Materials - Plastic
• Becoming integrated to replace/improve common
building materials
• Plastics are oil-based (hydrocarbons)
• Two general types
– Thermoplastics (melt, deform, vapourize = burns!)
– Thermosets (decomposes, only burns with extreme
temps)
24
Fire Effects on Common
Construction Materials - Plastic
• General Rule of Thumb when fighting fires
involving plastics…
–
–
–
–
Burn fast
Very intense heat
Dense black smoke
Extremely toxic
• Can resemble a Class B Fire (flammable liquids)
25
26
BREAK TIME
27
Roof Types
Three Main Types:
(a) Flat
(b) Pitched
(c) Arched
28
Occupancy Versus Type of
Construction
• Occupancy creates the fire load.
• Building codes specify building type based
on occupancy classification.
• Fire code determines fire protection based
on building and occupancy use.
• Occupancies are residential, commercial,
business, industrial and educational.
• Each type has a number of hazards.
29
Occupancy Hazards
30
Building Uses
• Ontario Fire Code and Ontario Building Code
separate buildings in groups A-F, as related to their
major use (or major occupancy)
• With each type of building comes various
requirements/restrictions on building construction
• Private dwelling residences are exempt (with some
exceptions)
31
Building Uses
• A – Assembly
– Theatres, libraries, schools, large bars, pubs and restaurants
• B – Institutional (compelled to sleep over)
– Jails, hospitals, orphanages, nursing homes
• C – Residential
– Apartment buildings (common area) , group homes, houses, motels
• D – Business and Personal Services
– Banks, barber shops, offices (medico legal), laundromat
• E – Mercantile
– Markets, stores, shops, supermarkets, restaurants, bars and pubs
• F – Industrial
– Flammable liquid plant, television studio, freight depot
32
Firefighter Hazards:
Structure Fires
• Change in occupancy creating an unusually heavy
fire load.
• Dangerous stockpiling and excessive stock
creating access problems.
• Unknown design errors, renovations, contractor
short cuts.
• Arsonists traps or tampering with fire protection
systems.
• Occupancy may not be what it appears.
(drug lab, boarding house, group home, etc.)
33
Construction Features Assessed
During Size Up
What constructions features are
important during size-up?
34
Construction Features Assessed
During Size Up
35
Firefighter Hazards:
Structure Fires
•
•
•
•
Combustible furnishings & finishes.
Wooden floors / ceilings.
Large open spaces.
Synthetic materials.
• Lightweight & truss construction.
36
Lightweight Wood or Steel Truss
Construction
=
Very Dangerous Firefighting
Conditions
37
Truss Roofs
38
39
40
Bowstring Truss!
41
Beware of the Truss!
42
Structural Collapse
• Every structure fire
has the potential for
collapse.
• Firefighters must be
aware and look for
indicators to
collapse.
43
Signs of Potential Collapse
• Prolonged exposure.(time)
• Distorted structural members.
• Fire on floors below heavy
machinery and heavy loads.
44
Signs of Potential Collapse
45
Building Collapse Zone
46
47
Size Up – What do you see?
48
The Back?
49
The Side?
50
Summary
• Firefighters must know & understand
building construction.
• There are five common types of
construction.
• Firefighters need to be aware of the hazards
associated with structure fires.
• Effects of fire on building materials.
• Signs of structural collapse.
51