Ch.5 Flashcards
The NFPA 220 has set a standard categorization for each type of Building Construction:
Type V: Wood Frame Type IV: Heavy Timber Type III: Ordinary Type II: Noncombustible Type I: Fire Resistive
Not included as a classification in NFPA 220 is ________ or __________
- multiple classifications
- interconnected construction types
In newer cities, construction methods are more recent, and most of the buildings fall within _____ to ______ construction.
Type III to Type I
The main point to remember in the performance of wood as a structural member is __________________
surface-to-mass ratio
______ is the key factor in fire performance of wood.
Mass
The second-most important point to remember in wood-frame construction is the ______________
Connection method
_____ was common throughout building construction from the 1800’s through the end of World War II
Ballon Frame
With the invention of _______, it became possible to build multistory wood-frame buildings faster and cheaper.
cheap machine-made nails
This type of construction involves a wood stud framing system in which the studs run continuously the full building height and there is no inherent firestop between floors:
Ballon Frame
__________ can often be identified by the doors and windows being stacked vertically.
Ballon-frame structure
The hazard associated with ballon-frame construction is the ability for the fire to __________________
Spread vertically and horizontally throughout the structure without visible indication
The __________, sometimes referred to as “western framing”, is the most common type of new frame construction in use today.
Platfrom Frame
In platfrom frame the wall studs are attached to a single board on the bottom called the _______
sill plate
Platform Frame construction:
- Began after the mid-20th century
- Used up to 3 story buildings
- Framing method creates compartmentation
- Identified by offset windows and doors
The ______ is a typical post and beam construction.
Barn
Barns have ________ floor and roof systems.
plank and beam
Dimensions of Post and Beam Construction:
- Min roof planks are 2 “
- Beams set 6 to 8 ft apart
- min post and beam are 4” x 4”
Post and Beam framing is usually easy to identify because the interior walls are usually ______
exposed
A framing method that resembles the post and beam, but uses much LARGER beams is being used today for large residential structures, commercial buildings, churches, and places of assembly:
Plank and beam
- Uses boards laminated together to from large beams
- Floors thick tongue and groove
- Reduces concealed spaces
Plank and Beam
The _______ is an engineered construction in which the entire structure is tied together into a unitized frame.
Truss
Truss Frame construction can be used for buildings up to ________ stories
3
The benefits for the construction industry for truss construction is that the light weight members are ________, ________, and _________
- less expensive
- easier to work with
- pre-engineered to span large openings
The truss is constructed of light weight, smallest-dimension lumber possible, typically _______
2” x 4”
Gusset plate is a metal plate about _____ thick that has been stamped to make a jagged teeth of one side.
0.05”
The bowstring truss is a __________
timber truss
Hackensack Ford fire collapse that killed 5 firefighters on July 1, 1988 was from _________
Bowstring truss
The bowstring truss can span areas of ___ to _____ feet and be spaced ______ on center.
- 50ft - 100ft
- 20 feet on center
If a building is old, it may contain ____ or ____.
And ____ and _____ can also play a part in the loss of structural integrity.
- dry rot or termites
- Fungus and decay
Defects in the wood members such as ____, _____, and ______ can weaken the members.
- warpage
- shrinkage
- torn or lifted grain
The fasteners used in most lightweight wood trusses used in construction today are MOST OFTEN referred to as __________
gusset plates
*They can also be called gang nailers, staple plates, or metal tooth plate connectors
The metal staple is designed to penetrate the wood form ____ to ____ inches, but can often be found with a penetration of less than _____ inches.
- 0.25” to 0.375”
- less than 0.25”
When used in roof systems ____ and _____ can cause plywood to deteriorate sue to high humidity and temperatures in attics and cocklofts.
-phosphates and sulfates
Heavy Timber construction can be referred to as _______
Mill construction
Heavy Timber is often found in ________
Old industrial buildings
Type IV: Heavy Timber:
- Columns greater than 8” x 8”
- up to 8 stories tall
- Floors typically 3” or greater in thickness &
- Built using 1” tongue and groove
Large sections of wood more than _____ thick can have more fire resistance than exposed steel.
6 inches
The exterior walls of the heavy timber construction are made of __________
masonry
The openings between sections of buildings separated by firewalls will have ___________ when subjected to heat.
fire doors that drop down or close
The hazard in heavy timber structures is that the walls and ceilings are _______________
unfinished and lack fire protection
Type III: Ordinary Construction:
- Masonry load bearing walls
- Wood-joisted floors and wood roof
- Thickness of walls 6 to 30 inches
- Walls thicker at bottom
- 1 to 3 stores tall, can be 10 stories
Fire-cut joists have a _____ degree cut on them.
30-degree
The Ordinary Construction building has load-bearing walls along the _________ of the building.
Floor and Roof joists span the __________
- longest part
- shortest distance possible
What symbols will indicate a spreader:
- a star
- letter S
- a channel
- a circle
- decorative device on exterior
2 types of spreaders:
Type 1- rod or cable runs parallel to joists and ties walls together
Type 2- Tensile member, rod or cable, runs perpendicular to joist and ties first three or four floor joists together
_________ employs building materials that will not add to the fire development
Type II: Noncombustible
Type II: Noncombustible:
- Structural material is metal-framed truss
- most common roof is metal decking
- then buildup, hot tar and gravel
- When walk on roof walk on side next to wall
____________ began the era of fire-resistive buildings.
The invention of steel and the use of steel as a building material
The typical rule of thumb for the expansion of steel is ___ inch for every ____ feet at approximately ____ degrees.
- 1” for every 10ft
- 800 deg
Many fire-resistive buildings are constructed with ___________ for floors and the roof.
reinforced concrete and steel bar joists
______ provides concrete with lateral strength.
Rebar
The top chord is _________ and the bottom chord is _____________
top-compressed
bottom- in tension
The top and bottom members of the truss are called _______
chords
The inside member of the truss is called the _____
web
The trusses are tied together with connecting members called __________
The connections are __________
- ties
- panel points
The most dangerous truss is the ___________
bowstring truss
The most common truss for ROOF construction is the ____________
peaked roof truss
Peaked Roof trusses are placed close together, ______ to _____ on center.
16 - 24 inches
If trusses were built prior to 1990, roof trusses were _______ to hold them in place
toe nailed into top plate of wall
Due to hurricanes, tornados, and roof failures, the method of securing roof trusses evolved to using _______________
- form of angled metal plate or metal clip
- referred to as hurricane clips, hurricane ties
Hurricane Clips are nailed to _____________ to better secure the roof structure.
Both the truss and the load bearing wall
One typical method of strapping during construction is to place a metal strap from the _____ of the load-bearding wall stud, over the truss, and back down to the ______ of the wall stud.
- outside
- exterior
The strapping method improves the roofs ability to withstand __________
Lifting forces
The __________ is used for both roofs and floors
parallel chord truss
The problem with the parallel chord truss in residential structures is ____________
the void space it creates (interstitial space)
Location for electrical wiring, HVAC, and other utilities in a parallel chord truss:
Interstitial space
The truss is designed to employ the ________ amount of building material to carry the designed load.
minimum
The shortcomings of truss construction method is:
the connectors
Wood carries its load by _________
mass
In unprotected steel trusses, the steel can begin to lose strength at ______ and fail around ________
- 800 degrees- lose strength
- 1000 degrees- Fail
Both of these products have helped the building industry span larger open distances with load-bearing ability, and at a lower cost.
- The Laminated Beam
- Engineered I-Beam
The top and bottom boards of an I-beam are referred to as __________
flanges
The flanges are typically solid wood, whereas the web is ___________________
- plywood
- OSB
- type of wood laminated together
The primary hazard associated with the I-Beam is that it is _______________
relatively lightweight and therefore more susceptible to deterioration and failure under fire conditions
Composed of a number of wood pieces sized and arranged according to design needs, glued together:
Laminated Beam
Types of wood-frame buildings:
- Ballon Frame
- Platfrom Frame
- Post and Beam
- Plank and Beam
- Truss frame
A metal plate, sometimes referred to as a gusset plate, that has teeth that enter the wood member to hold them together.
Panel Point
A framing method that uses heavier beams that are spaced much farther apart than the traditional 16 inches. It is used in modern construction.
Plank and Beam
A connecting member, such as a gusset plate, that holds the truss members together.
Tie
Common throughout building construction from the 1800’s through the end of World War II?
Ballon Frame
