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Government Engineering College,
Rajkot
Branch - Civil
Subject – Building Construction
Presented By---130200106005_2130607
BUILDING CONSTRUCTION
Why Know Building Construction
 To alert you to potential construction hazards,
 To enable a safe and effective fire attack,
 By knowing basic building construction types, we can approximate how fire
will spread and allow us to extinguish it quickly,
 “The building is your enemy… know your enemy” Francis L. Brannigan.
Classification of the Construction
Sector
3 Basic
Headings
Residential
Building
Construction
and Civil
Engineering
NonResidential
Building
Civil
Engineering
3 Categories
of Input
Resources
50 Input Resources
Machinery
38
Materials & Products
Equipment
5
Equipment items
Labor
7
Labour services
Machinery
38
Materials & Products
Equipment
5
Equipment items
Labor
7
Labour services
Machinery
38
Materials & Products
Equipment
5
Equipment items
Labor
7
Labour services
5
Types of building construction
 There are TWO basic types of construction: “It either burns
(combustible) or it does not burn (noncombustible)”
 All buildings in the US are constructed by one of the five construction
categories;
 Type “1” - Fire Resistive – Least Combustible
 Type “2” - Non-Combustible
 Type “3” - Ordinary
 Type “4” - Heavy Timber
 Type “5” - Wood Frame – Most Combustible
 Four of the five types have subgroups “A” & “B”.
 Subgroup “A”:
Subgroups
 Means Protected;
 all structural members have an
additional fire rated coating or cover by
means of sheetrock, spray on, or other
approved method,
 the additional fire rated coating or cover
extends the fire resistance of the
structural members by at least 1 hour.
 Subgroup "B“:
 Means Unprotected;
 all structural members have no additional fire
rated coating or cover,
 exposed members are only fire resistant according
to their natural ability, characteristics, and fire
rating.
Type 1: 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.
Type 2: 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.
Type 3: 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.
 buildings have been constructed in two distinct types;
 Older – late 19th and early 20th century and,
 Newer.
 “Older” buildings;
 tongue and grove floor boards,
 solid lumber joists and rafters ( can be 3” x 10”),
 columns could be added for additional support
 room size limited by span of supporting element,
 floor joists commonly have a “fire cut” on each end to keep floor
joists from pushing the wall down,
 1” to 1 ½” wooden planks commonly used in the roof assembly.
 “Newer” buildings;
 flooring may consist of plywood, oriented strand




board (OSB),
laminated veneer lumber (LVL), and parallel
strand lumber (PSL), supported by
lightweight wooden trusses, and wooden I- beams,
these supports are more likely to collapse sooner
than larger solid lumber joists,
roof construction using lightweight materials.
One & Two
Family
Residential Type building
Multiple Residence type
Commercial and Residential type
Two story commercial Type building
Hazards Related Type Construction
 Stability of masonry walls,
 Stability of interior column, girder and beam system,
 Void spaces,
 Excessive fire loads, “dead” loads (HVAC, Solar Arrays)
 Bow string truss roof,
 Alterations can have an effect on the building,
 The largest concealed space is the “Cockloft”, an open space for fire and
smoke spread,
 Braced Wall Spreaders- danger – wall can be out of alignment.
Solar Arrays and HVAC Units
A basic sign that a wall is in distress
Braced Walls
Braces of unprotected steel or cable will fail at fire temperatures
Arrows mark locations where star-shaped anchor plates were
located on the west-side of the theater building that was adjacent to
the fire building. The anchor plates appear to have been attached to
the ends of the heavy timber roof trusses supporting the roof and
also to some of the second-floor joists. NIOSH F2011-15
Photo shows star-shaped anchor plates located on the D-side wall in
the area that collapsed. NIOSH F2011-15
TYPE-4-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.
TYPE-4-Heavy Timber
structural frame, columns, etc. – heavy timber
 exterior bearing walls – 1 hour heavy timber
 interior bearing walls – 2 hour rated
 floor construction, beams and joists – heavy timber
 roof construction, beams and joists – heavy timber
 Characteristics;
 heavy timber construction is one of the oldest types of buildings used in
this country,
 heavy timber buildings were originally designed and used as multi-story
industrial or storage occupancies,
 fire resistance is attained by placing limitations of minimum sizes on wood
structural members and minimum thickness and composition of wood
floors and roofs,
 will have four bearing exterior walls,
construction includes columns not less than 8” thick in any dimension,
 beams and girders not less than 6” x 10”,
 roof framing is not less than 6” wide x 8” depth,
 floors and roofs have thicker than normal construction consisting of varying
layers of materials that build up to a deck of 3” thick to 4” wide,
 arches and trusses not less than 8” thick in any dimension.
 usage of approved fastenings and adhesives,
 lumber may be sawn or laminated,
 usually found in very old mills, factories, and warehouse, and in older
churches,
 exterior walls are noncombustible,
 interior structures made of solid or laminated wood with no concealed spaces,
 does not have plaster walls & ceilings covering interior framework,
 wood has large dimensions, much heavier, more difficult to ignite, can
withstand fire for longer time frames,
 primary fire hazard - combustible contents of structural members,
 does not fail early in a fire,
 because of massive amount of combustible materials there will be serious heat
given off and may pose exposure protection problems,
Heavy Timber Frame building
Heavy Timber columns, beams &
girders
Masonry walls
Large open spaces, lack of hidden voids
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
“Silent Flooring”
Poor Construction Methods
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.
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.
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.
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.
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, vaporize = burns!)
Thermosets (decomposes, only burns with extreme temps)
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)
Roof Types
Three Main Types:
(a) Flat
(b) Pitched
(c) Arched
Truss Roofs
Bowstring Truss roof!
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)
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
The Different Parts Of Building, When It Is Being Constructed……..
Some World’s Top Class Building Structures
Burj Khalifa
Dubai
Empire State
Building
New
York,USA
Gherkin
London,
UK
Petronas
Twin
Towers