Building Construction (ch.2) Flashcards
A working knowledge of building construction not only provides the necessary expertise to conduct a quick and accurate size-up of a structure, it also provides the foundation for effective, timely, and safe operations in the following areas: x3
- Structural integrity
- Ladder placement
- Forcible entry / Search and rescue
- Ventilation feasibility
Ladders should be placed to the______ of the building.
Strong area
A size up consists of three operations;
- Analyze the situation
- Decide a plan (strategy)
- Put the plan into operation (tactics)
Type and construction of building will indicate;
X5
- Rate of burning
- Possible avenues of fire spread
- Problems that will have a direct impact to confine fire
- Structural integrity
- Time necessary to conduct safe foreground operations
4 construction methods
- Metal concrete
- Masonry
- Frame/stucco
- Curtain
_____ utilizes structural members that depend on size for strength
Conventional construction
Lightweight truss construction does not derive strength from size. Strength is obtained from multiple members that are in ____ and ____
Compression and tension
A single lightweight structural member can span ____ and may be compromised of ___x____
70 ft ; 2x4’s
In a truss gable roof the rafters are ___ of the truss. The ceiling joists are ___ of the truss
Top chord; bottom chord
___ x___ and ___x___ are the standard for lightweight construction.
2x3’s and 2x4’s
Conventional construction will utilize a minimum of x
2x4s
The ability to accurately estimate the amount of time that a structure can be considered structurally strong is dependent on what factors. X3
- Type of construction
- How long the fire has been burning
- Fire intensity
Roof styles x6
- Gable
- Hip
- Flat
- Bridge
- Arch
- Saw tooth
- gambrel
Gable roof, A frame configuration of conventional or ordinary construction that consists of a ridge board and rafters that cross the outside walls; rafters are usually ___X___ in or larger and are usually ___ in to ___ in on center
*spaced up to ___ in for steep pitched roofs
2x6” ; 16” to 24”
36”
Metal gusset plate connectors may vary in size, thickness, and depth of penetration. The most common are ______ steel plates with prongs that produce _____inch penetration.
18 gauge, 3/8”
Eighteen-gauge “roof truss clips” may be found nailed to the bottom chord (every ____ to ____ trusses) and top plate of interior walls.
3 to 5 trusses
Common on center spacing for truss rafters is
24in
Conventional construction utilizes ridge boards and rafter of ____X____ or larger
1x6”
When metal connector plates and surrounding wood are exposed to fire, the connector plates will quickly fail by _____
Pulling out of the wood
Newer roofs use ____ or ____ in plywood as decking instead of 1x4 or 1x6 in space sheathing
3/8 or 1/2”
___ rafters are utilized where two rooflines join together
Valley rafters
Bridge truss roof; constructed during 1930’s and 1940’s. Wooden truss members are built from ____X___ in lumber
2x12”
Bridge truss roof; rafters are ____ in and covered by ____ in sheathing.
Straight sheathing used ____
Diagonal sheathing used _____
2x6 rafters ; 1x6 sheathing
Straight = pre 33
Diagonal = post 33
- expect plywood for earthquake ordinance
Bowstring arch truss; _____ or ___ lumber comprises the arch truss and related members.
2x12 or 2x14” lumber
An egg crate , geometric or diamond patterned roof:
Lamella arch roof
Lamella arch constructed from ____ in wood framing with steel plates and bolts at junctions of framing
2x12in
Lamella arch roof; this type of arch is supported by _______ or _____
Exterior buttresses or internal tie rods with turn buckles
Although these roofs offer some protection when exposed to fire, total roof collapse may occur if fire removes more than ____% of the roof structure. Total roof collapse of the roof can result from “the domino effect.”
20%
An arch roof that uses metal tie rods to offer support for the walls of the building
Tied truss arch roof
Tie rods usually ___ in in diameter to ensure arches do not push exterior walls outward
5/8 in
Tied truss arch; rafters are ___X___ or larger
2x10”
Sawtooth roof; rafters are ____ in or larger.
Sloping portion is covered with _____ sheathing or ____ plywood
2x8in
1x6in sheathing or 1/2” plywood
Wooden I beam; the stem is joined to the top and bottom chords by a continuous glued edge joint. And may be constructed from ____ in plywood or chip board of the same thickness
3/8
Wooden I beam; nail8ng blocks are placed perpendicular to the top chords and are spaced ___ ft apart
4ft
Open web; the steel tube web members are prefabricated from ___ to ___ in cold rolled steel tubing with the ends pressed flat
One to two in
Open web ;Spans to ___ ft are possible
70ft
Metal gusset plate roof; utilization of 2x4s in a span of up to___ ft
decking is usually _____ in plywood. Dwellings will use ____ in or ___ in
1/2in
3/8 or 1/2
Panelized roof; may be found on ____, ____, or ____ buildings
Wood masonry, or concrete tilt slab
4 main components of panelized roof and sizes
Beams 6x36
Purlins 4x12
Joists 2x4
Plywood 1/2”
Panelized roof;
Beams are supported at their ends by ____,____or ____, or ____
Pilasters, wood or steal posts, or saddles
Panelized roof;
Beams are spaced ___ to ___ ft apart
12 to 40 ft
Beams may be bolted together to provide lengths well in excess of ____ ft
100ft
Panelized roof;
Beam span supports of _____ in hollow steel pipe
4in
Open web bar joists;
Top and bottom chords are usually made from ____ in steel and web supports are solid ____ in steel bar
1/8” chords; 5/8 in web
Open web bar joist; large build8ngs may have bar joists used as girders spaced up to ___ ft. Joists are spaced ___ ft apart to accept corrugated metal decking
45 ft; 8ft
Steel begins to lose its strength at _____
1000 degrees
Light weight concrete;
A steel or wood sub structure is covered by corrugated metal ( Robertson decking). An air entrained mixture of sand, cement, and occasionally pea gravel is pumped on top of the corrugated metal decking and ______ in or _____ in wire mesh to a thickness of ___ to ___ in
4x4 in or 6x6in wire mesh;
3 to 4 in thick
In concrete roofs use ____ or ____ blade to cut ventilation openings
Diamond or carbide tip blade
When exposed to sufficient heat metal beams can expand ___in per ____ ft
9inches per 100’
Tilt up buildings can be up to ___ stories in height
5
Masonry buildings constructed up until 1930’s;
X7 indicators or URM
- brick exterior walls about ____ inches thick
1.concrete cap
2. Rafter tie plates
3. Bond Beam cap
4. Lintel
5. Inset windows
6. Shelf
7. Kings row
13in walls
URM pre 33;
Parapet walls can be ____ ft above the roof line and ___ ft or more if used as facade on front of building
3ft; 5 ft + facade
Long Beach earthquake of ____
1933
Long Beach earthquake revisions
X5 (walls and sheathing)
- exterior walls at least 9 in thick
- Masonry walls reinforced with “rebar”
3.all joists/rafters required to be anchored to exterior wall( ledger board rafters hung by hangers) - Cement mortar instead of sand and lime mortar
5.diagonal roof sheathing.
Tehachapi earthquake of ______
1959
Tehachapi earth quake retro ; x3
- A 4 to 6 in concrete bond beam cap on top of lowered parapet walls along public ways and exits
2 parapet walls should not be higher than 16 inches including bond beam cap - Exterior walls drilled at roof level and a steel anchor bar/rod installed ever 4 feet (rafter tie plates).
1959 ordinance
Parapet walls no higher than_____
16in
1959 ordinance;
Size of concrete bond beam cap
4 to 6 in
The soul are earthquake of _____
1971
The Selma earthquake ordinance designed to prevent exterior walls from collapsing outward by stabilizing the building by: x2
- Anchor walls to floor and roof ( tie plates to floor joists/ diagonal bracing)
- Strengthening roof construction (plywood, metal straps)
A bond beam cap of concrete on top of parapet walls. Concrete bond beams may also been added for strength ________ and between _____
Over windows and between second floors of multi story buildings
URM;
In every ___ to ___ row of bricks, one row will be laid on end
Fourth to seventh
Additional URM modifications may include;
Metal straps across the width of the roof and attach to opposing walls. The straps are usually ____ of the length of the building back from the front and rear walls
1/3
Additional URM modifications may include; remove layers of composition and cover the sheathing with ____ plywood
1/2 plywood
Exterior walls may suddenly collapse outward a distance that is _______ the height of the wall
Equal to at least
URM modifications;
Metal straps may be found ___ to ___ ft from walls
3 to 4
Vertical spread of fire through the walls is a possibility . However this is controlled by horizontal ______
Fire blocking
The following 4 areas should be considered when confronted by facade construction
- Overhang
- Facade height
- Supported or unsupported
- Height from roof
If a facade is exposed to fire , expect the facade to collapse outward at least_____
The distance of overhang
These buildings were constructed during the 1920’s, 1930’s and 1940’s, and are primarily utilized in single family dwellings and multi-story habitational occupancies up to _____stories.
4
A pair of wires suspended by ____ insulators and pass through ____ tubes.
Ceramic
Curtain construction; depending on the particular method that is employed, curtain construction can be ____ % faster than conventional construction
60%
