Chapter 3 Building Construction

Question 1

Types of Building Construction

Answer 1

Type 1- Fire-resistive
Type 2- Noncombustible or limited combustible
Type 3- Ordinary
Type 4- Heavy Timber
Type 5- Wood Frame

Question 2

Type 1

Answer 2

Fire Resistive
Provides structural integrity during a fire

• Structural members, including walls, columns, beams, floors & Roofs made of noncombustible or limited combustible materials.
• Fire-resitive compartmentation provided by partitions & floors tend to retard the spread of fire.
• Primary Hazard “Contents”
• FF can launch an interior attack with confidence
• Fire can spread by opening in partitions & improperly designed heating & cooling systems.

Question 3

Type 2

Answer 3

Noncombustible or limited combustible

Similar to type 1. Degree of fire resistance is lower.

• Fire resistance ration on all parts of structure (exterior & interior load bearing walls, building materials.
• No fire resistance rating such as wood “can be used in limited quantities”
• Primary concerns, contents of building, Heat can cause structural supports to fail, Type of roof “Flat built-up roofs. Felts, insulation & tar

Question 4

Type 3

Answer 4

Ordinary
-Exterior walls & structural members constructed of noncombustible or limited combustible materials.

• Interior members (Walls, Columns, Beams, Floors & Roofs are completely or partially wood.)
• Primary concern- Fire and Smoke spreading through concealed spaces.

Question 5

Type 4

Answer 5

Heavy Timber
- Exterior & Interior walls & their associated structural members made of noncombustible or limited combustible materials.

-Other Interior structural members, including, Beams, Columns, Arches, Floors & Roofs, are made of solid or laminated wood with no concealed spaces.
(Old factories, Mills, Warehouses, Churches)

*Primary Hazard= Massive amounts of combustible contents, Tremendous amounts of Heat & Exposure protection problems.

Question 6

Type 5

Answer 6

Wood Frame
-Exterior walls, bearing walls, floors, roofs & supports made completely or partially of wood or other approved materials.

• Commonly typical single-family residence
• Unlimited potential for fire extension with building of origin & to nearby structures

-FF must be alert for fire coming from doors & windows extending to the exterior of the structure.

Question 7

Load Bearing Wall

Answer 7

Walls that take loads (Party walls)

Most exterior walls are load bearing walls

Question 8

Party Wall

Answer 8

A load bearing wall that supports two adjacent structures.

Question 9

Partition Wall

Answer 9

Divides two areas within a structure and is a non-load bearing wall

Question 10

Wood

Answer 10

Reaction of wood to fire conditions depends on two factors

• Size of Wood
• Moisture content ( Green Wood)

Question 11

Masonry

Answer 11

Bricks, Stones, Concrete ( Minimally affected by fire & Exposure to high temps)

• Commonly used for Fire Wall assemblies

Question 12

Cantilever Wall

Answer 12

Free standing fire walls commonly found on large churches & shopping centers

Question 13

Block Wall

Answer 13

May be load-bearing walls

Most Brick and stones walls are Veneer walls

Question 14

Veneer Wall

Answer 14

Decorative & usually attached to the outside of some type of load-bearing frame structure.

Question 15

Bricks
Stones
Blocks

Answer 15

• Rarely show any signs of floss of integrity or serious deterioration
• May Spall or lose small portions of their surface when heated
• May Crack but usually retain most strength & basic structural stability
• Motor between bricks, blocks, & stone are subject to more deterioration

Question 16

Cast Iron

Answer 16

Rarely used in modern construction

*Primary Concern is stand pipe bolts or other connections can fail

Question 17

Steel

Answer 17

Primary material used for structural supports in modern buildings.

• Elongate when heated (50’ beams may elongate as much as 4” @ 1000 degrees)
• If restrained @ ends it buckles & fails somewhere in middle.

Question 18

Reinforced Concrete

Answer 18

Internally fortified with steel reinforcement bars or mesh.

• Doesn’t perform particularly well under fire conditions. Loses strength & Spalls

Question 19

Gypsum

Answer 19

Inorganic product from which Plaster & Plasterboards are made

• High water content
• Provides insulation to steel & wood

Question 20

Glass/Fiberglass

Answer 20

• Wire-reinforced glass has some thermal protection

- Typically used for insulation purposes

Question 21

Two primary types of dangerous conditions that may be posed by a particular building

Answer 21

• Conditions that contribute to the spread & Intensity of the fire
• Conditions that make the building susceptible to collapse

Question 22

Fire Load

Answer 22

Maximum heat that can be produced if all the combustible materials in a given area burn.

Question 23

Heavy Fire Loading

Answer 23

Large amounts of combustible materials in an area of a building.

• Most critical hazard in commercial & storage facilites can quickly override sprinkler systems.

Question 24

Collapse zone

Answer 24

One and a half times the height of the building

Question 25

Lightweight & Truss Construction Hazards

Answer 25

Two most common
Usually fail in 5-10 minutes

-Lightweight metal steel bar bent at 90 degree with flat or angulated welded to top and bottom
/\/\/\/\/\/\/\/\

• Lightweight wood 2x3 or 2x4 connected by gussets.

Question 26

Gusset Plates

Answer 26

Small metal plates (18 to 22 gage) with prongs that connect into wood 3/4”

Question 27

Bow String Tusses

Answer 27

Building with large openings (car dealerships, Bowling alleys, Factories & Supermarkets)

Question 28

Trusses are designed to work as a integral unti

Answer 28

• Some are in tension (Vertical & Horizontal stresses that tend to pull things apart)
• Some are in Compression ( Vertical & Horizontal stresses that tend to press things together.)

Question 29

Construction, Renovation & Demolition

Answer 29

• Additional fire load & ignition sources( Open flames, Torches, Grinding, Cutting) by contractors
• Subject to rapid fire spread while partially completed, lack of doors and widows spread fire
• Arson, Poor house keeping prevents egress.