Building Construction Drill

Question 1

Structural integrity

Answer 1

The effects from a fire on a particular type of construction, building or roof

The integrity of a working surface

Question 2

Ladder placement

Answer 2

Placed to the strong areas of a building

Question 3

forcible entry and search

Answer 3

best avenues t enter and exit the structure

Question 4

ventilation feasibility

Answer 4

can ventilation be safely conducted

Question 5

conventional construction

Answer 5

utilizes structural members that depend on size for strength

the greater the span of a structural member, the larger it has to support a given load

the size of the structural members dictate the time necessary for failure when exposed to heat

Question 6

Lightweight construction

Answer 6

strength is obtained from multiple members that are in compression and tension

The strength of the individual structural member is dependent on the total sum of the other members; therefore, if
one member fails, others may fail.

Question 7

Conventional vs Lightweight construction

Answer 7

members can be separate and distinct (ex a ridge board and rafter on a gable roof that collapses on the ceiling joist)

lightweight depends on the sum total of the members. If one unit fails, the rest can fail (rafters, roof decking, and ceiling joist all to collapse)

Question 8

Conventional Vs Lightweight Gable Roof

Answer 8

Conventional- rafters 2x6 or larger 16-24” on center, 1x6” ridge boards or rafters butted up together, ceiling joist/collar beams typically 2x4”

-Steep pitched roofs up to 36” rafter spacing

-Commonly utilize 1x4 or 1x6 spaced sheathing

-Convention gable construction will last longer. Strong areas of the roof are the ridge and the area where the rafters cross the outside walls

Lightweight: 2x3” or 2x4” wood trusses held together by metal gusset plates spaced 24” on center.

-Trusses have top/bottom cords in compression/tension and webbing. Bottom cord acts as the ceiling joist in lightweight construction which may not rest on interior walls.

-Metal gusset plates are 18 gauge steel plates with prongs that produce 3/8” penetration. Connector plates will pull out of wood under fire causing collapse

-Truss members may only be supported at their outside edges unless used as a cantilever truss. Partition walls may not support the truss unless 18 gauge roof truss clips (found at every 3-5 trusses) are used. This can contribute to total collapse.

-Commonly use 3/8” or 1/2” plywood decking which burns faster

Question 9

Compression / Tension

Answer 9

Tension- beam or member is pulling on the member (pull the joints together)

compression- beam is pushing on the joints from either end of the beam (push the joints apart)

Question 10

Lightweight construction members

Answer 10

2x3s and 2x4s are the standard

Question 11

Conventional construction members

Answer 11

2x4s and up

Question 12

corrugated construction

Answer 12

utilize a sub structure of wood or steel, covered with corrugated steel, aluminum or fiberglass.

They are easily erected, can be utilized in various types of applications, and are easily
identified by their characteristic “corrugated” appearance.

Question 13

Corrugated construction hazards

Answer 13

The corrugated portions of these buildings will quickly fail when subjected to sufficient heat or fire

steel loses its tensile strength at 1000 degrees F, and aluminum or fiberglass offers little
resistance to fire. Roof ventilation operations on these buildings should be considered extremely
dangerous.

Question 14

Metal Beam

Answer 14

sub-structure of steel beams, usually coated with a sprayed on fire retardant material.

This skeleton is then finished with an exterior of concrete, masonry, glass or similar materials

vary from 2 stories to high rise

Question 15

Metal Beam construction hazards

Answer 15

Vertical extension of fire and smoke to upper floors is enhanced in buildings with multiple floors.

Falling panels of glass or other building materials.

when exposed to sufficient heat, metal beams can expand 9” per 100ft which can push out walls

Question 16

Curtain Construction

Answer 16

-Curtain construction methods: using prefabricated panels to bolt into the substructure/steel beams to cut the time needed to complete multi-story and high-rise buildings by about 60%

-A building façade’s dead load is transferred to the main building structure through connections at floors or columns of the building.

-These panels are bolted to sheet metal or aluminum outriggers/struts that are attached to steel beams.

-Pre-fabricated panels can be made from materials such as lightweight concrete, slate, granite, stone veneer, fiberglass, glass panels, etc.

Question 17

Concrete construction methods (Tilt Up)

Answer 17

made of concrete slabs that have been “tilted up” into place to form exterior walls of a structure. These buildings are easily identified by their exterior appearance and can be up
to five stories in height.

Question 18

Curtain Construction Hazards

Answer 18

Expect the panels to fail and fall due to metal struts losing tensile strength

Question 19

Tilt Up Hazards

Answer 19

Lightweight roof construction may be comprised of 2” x 4”s or 2” x 3”s in tension and compression
and extensive use of ½ inch plywood. These contribute to rapid spread of fire and early roof
collapse. Ventilation operations on this type of roof are dangerous unless personnel are properly
trained.

Facades have also become popular which contributes to area of fire spread

Question 20

Masonry construction methods (Brick) Pre 33

Answer 20

ordinary brick construction and present
extreme hazards to firefighting personnel under fire or earthquake conditions

Mortar consisting of sand and lime only, no cement.
Lack of steel reinforcing rods (“rebar”).
Brick exterior walls about 13 inches thick.
Parapet walls around the perimeter of a roof. Parapet walls can be three feet above the roof
line, and five feet or more if used as a facade on the front of a building.
Floor and roof joists that are “let” (penetrated or resting in a cavity) into the inside of the
exterior walls.
Straight roof sheathing.
Roof and floor joists that are “fire cut” (ends were cut with an angle) so they would pull loose
from the exterior walls during a fire and collapse into the interior of the building without
pulling down the exterior walls.

Question 21

masonry construction methods (brick) post 33

Answer 21

Long Beach Earthquake

Exterior walls are required to be at least nine inches thick.
Masonry walls are required to be reinforced with steel “rebar.”
All joists and rafters are required to be anchored to exterior walls. This is usually
accomplished by bolting a “ledger board” to a masonry wall and attaching the joist and rafters
to the ledger board with metal hangers.
Cement utilized in the mortar.
Diagonal roof sheathing.

Question 22

Masonry construction methods (brick) post 1959

Answer 22

Tehachapi Earthquake

A four to six inch concrete bond-beam cap to be laid on top of lowered parapet walls along
public ways and exits.
Parapet walls should not be higher than 16 inches including the bond-beam cap, and most
importantly;
Exterior walls drilled at the roof rafter level and a steel anchor bar/rod installed every four
feet and attached to the existing roof rafter. This modification rendered the fire cut of the roof
rafter ineffective. The steel anchor bar/rods are secured to the exterior of the building by a
plate/nut combination that is known as “rafter tie plates.”

Question 23

masonry construction methods (brick) post 1971

Answer 23

Sylmar Earthquake

Anchoring walls to floor and roof systems.

Strengthening roof construction (plywood, metal straps, etc.)

Add steel bracing from parapet walls to roof structural members.

Metal straps across the width of the roof and attached to opposing walls. The straps are usually 1/3 of the length of the building back from the front and rear walls.

Remove the layers of composition and cover the sheathing with ½ inch plywood. This decking is then recovered with composition.

Question 24

Brick identification

Answer 24

Rafter tie-plates on the exterior of a building (rafter tie-plates can be found on remodeled
“new” appearing buildings). These exterior plates on a masonry building indicate that the
joists and rafters of the building are anchored to the exterior walls.
A bond-beam cap of concrete on top of parapet walls. Concrete bond-beams may also have
been added for strength over the windows and between the second floors of multi-story
buildings. This is a common technique used for additional strength for exterior walls.
Deeply recessed window frames. Window frames are “set” to the inside of the wall, thereby
exposing about eight-inches of brick return on the exterior of a building. Remember, these
walls are at least 13 inches thick.
Windows may have arched or straight lintels.
The lime mortar between the bricks is white, porous, sandy, and may be easily rubbed away by
a fingernail, knife, etc. In some cases, the bricks have not been uniformly laid and the
workmanship appears sloppy.
In every fourth to seventh row of bricks, one row will have been laid “on-end.” This row of
bricks is referred to as the “king row” and is for additional strength.

Question 26

unreinforced masonry hazards

Answer 26

wall, roof and floor collapse

Unreinforced masonry construction that is held together with lime,
mortar, and sand creates a weak wall, particularly after the lime mortar has deteriorated with age
and/or is subjected to heat from a fire

When arch roofs (particularly the bowstring and tied truss) are
modified as per the Earthquake Ordinance, the additional roof stability provided by plywood and
metal straps can increase the potential for collapse of front/rear walls

safe areas-
1. The corners of a building.
2. A distance at least equal to the height of the walls away from a building.

Question 27

block construction

Answer 27

These buildings are primarily concrete block that form the exterior walls. This type of construction is
strong and extensively utilized

Question 28

block construction hazards

Answer 28

It is common to find this type of construction supporting lightweight floor joists and roofs
(depending on the age of the building). Facades are also common on this type of construction

Question 29

Frame/Stucco Construction Methods

Answer 29

tructurally sound, the stucco exterior walls can support extensive remodel additions and/or
conventional or lightweight construction

Question 30

unreinforced masonry indicators

Answer 30

Recessed windows
Bond-beams over the windows
Rafter tie plates

Add steel bracing from parapet walls to roof structural members.
Metal straps across the width of the roof and attached to opposing walls. The straps are
usually 1/3 of the length of the building back from the front and rear walls.
Remove the layers of composition and cover the sheathing with ½ inch plywood. This decking
is then recovered with composition.

Question 31

frame/stucco construction hazards

Answer 31

Vertical spread of fire through the walls is a possibility (if balloon construction is present). However,
this is controlled by horizontal fire blocking, if present.
Lightweight construction. The age of the building is a key factor in identification of this construction

Question 32

Facades

Answer 32

A facade can be defined as an “identifiable style of construction on the exterior of a building that will
conceal and spread the travel (extension) of fire.” To summarize, facades are external attics.

Facades are utilized to conceal equipment and machinery on flat roofs.

Question 33

4 areas of a facade

Answer 33

overhang- the distance it extends from the building. As the size or extension from the building increases, so should concern about structural stability when a facade is exposed to fire. As the size of a facades increases, so does its complexity and the materials utilized in this construction. The size of a facade will have a direct effect on the area (what there is to burn) and the path and travel (extension) of a fire. Additionally, the extension of fire will be affected by the presence or lack of “fire stops.”

facade height-Facade height (B) and shape will effect stability, the amount of building material utilized, and the potential path of fire.

supported or unsupported-The structural stability of a facade will be enhanced if supported (C) by pillars, posts or other means that are often used for style of decoration.

height from roof- When confronted by a facade, an area that is often neglected is the distance from the facade to the actual roof line (D). Facades normally hide or conceal the roof line.

Use scuppers to indicate actual roof line

Rafter tie plates indicate where rafters are

Question 34

Bungalow and Balloon Construction

Answer 34

1920s, 30s and 40s

-Different styles emerged throughout the eras, including Victorians/Queen Annes, Craftsman’s, and California Bungalows

-Single family dwellings or multi-story condo type occupancies up to 4 stories

-Bungalows commonly have no ridge board w/ 2x3” or 2x4” rafters butted up against each other or a 1x6” ridge board

-Commonalities:

1) Raised foundations which may or may not have a basement/subfloor

2) Steep-pitched roofs

3) Spaced sheathing

4) Tongue and groove or shiplap siding

5) Lath and plaster

6) Knob and tube wiring

Question 35

Balloon Construction Hazards

Answer 35

-exposure problems due to all-wood construction, termites, renovations which affect structural integrity.

-No fire blocks, studs which extend all the way to the roof without separation, allowing rapid fire spread up and down.

-Knob and tube wiring can be an electrical hazard if utilities not shutoff

-Crawl space or basement creates an area under the floor where you can fall into. Also fire can begin in the basement and spread rapidly into the attic space making you think it is an attic fire

Question 36

Curtain Construction hazards

Answer 36

Expect the panels to fail and fall due to metal struts losing tensile strength