Building Construction:
Chapter 11: Roofs(91
questions and answers)
What does a roof slope of 3 to 12 designate?
Low Slope Roofs: 3/12
Medium to High Slope: 4-12/12
What does the type of roof covering depend on?
Form of the roof structure
The slope of the roof
Local Climate
Appearance Design
What are the components of a flat roof?
Vapor Barrier
Thermal Insulation
Roofing membrane
Drainage layer
Wear course
What are some operational problems of fires involving clay, slate, and
cement tiles?
a. Tiles can become loose and fall from a roof as the deck burns away and
nails lose their grip or as firefighters conduct ventilation operations
b. The surface can become slippers, posing a serious fall hazard. Proper
equipment and caution should be used at all times
c. The thin pieces of slate are brittle and may have sharp edges, creating a
hazard for firefighter below.
What are the test procedures contained in NFPA 256?
Intermittent flame exposure test
Burning brand test
Flying brand test
Rain test
,Weathering test
Spread of flame test
What pitched roof consists of two inclined surfaces that meet at their high
side to form a ridge?
Gable
A ___________ roof is designed to provide light and ventilation.
Sawtooth
What type of roof is created from triangles arranged in 3 dimensions to form
a nearly spherical surface?
Geodesic Domes
What is the best indicator that a roof is weakening?
Any indication of advanced or heavy fire development
Fireproofing can be omitted from roof supports when the roof is located more
than __________ feet above the floor in an assembly occupancy.
20
Flat roofs must be designed to support the weight of:
A few workers
Rafters may be constructed by the following types of materials:
Rafters may be constructed by the following types of materials:
Wood
Steel Beams
Steel Trusses
What makes trusses vulnerable to early failure under fire conditions?
Reduced mass of components
A ____________ truss uses a curved top chord.
Bowstring
What type of trusses are most common for pitched roofs?
Pratt
What is considered the portion of roof construction to which the roof covering
is applied?
, Roof Deck
What materials are used for construction of roof decks?
What materials are used for construction of roof decks?
Plywood
Wood Planks
Precast gypsum planks
A vapor barrier is needed when the outdoor temperature is below:
40F (50C)
What type of membrane roofing uses several overlapping layers of roofing
felt saturated with tar or asphalt?
Build Up
What is the major difference between flat and pitched roofs?
Water immediately drains from a pitched roof
What type of roof coverings are effective against a light fire exposure?
Class C - Light Fire Exposure
What types of roofs involve the use of the roof surface of a building for a
rooftop garden?
Green
What type of roof produces clean and reliable energy?
Photovoltaic (Solar Energy)
What are small structures erected on the main roof of a building?
Penthouses
True or False: Roofs are generally as strong as floors since they must endure
extensive dead loads and demanding live loads such as snowpacks and high
winds.
False
What are special dangers posed to firefighters by flat roof structures?
Flat roofs create a false sense of security for firefighters
What type of pitched roof has square ends in which the end walls of the
building form triangular areas beneath the roof?
Chapter 11: Roofs(91
questions and answers)
What does a roof slope of 3 to 12 designate?
Low Slope Roofs: 3/12
Medium to High Slope: 4-12/12
What does the type of roof covering depend on?
Form of the roof structure
The slope of the roof
Local Climate
Appearance Design
What are the components of a flat roof?
Vapor Barrier
Thermal Insulation
Roofing membrane
Drainage layer
Wear course
What are some operational problems of fires involving clay, slate, and
cement tiles?
a. Tiles can become loose and fall from a roof as the deck burns away and
nails lose their grip or as firefighters conduct ventilation operations
b. The surface can become slippers, posing a serious fall hazard. Proper
equipment and caution should be used at all times
c. The thin pieces of slate are brittle and may have sharp edges, creating a
hazard for firefighter below.
What are the test procedures contained in NFPA 256?
Intermittent flame exposure test
Burning brand test
Flying brand test
Rain test
,Weathering test
Spread of flame test
What pitched roof consists of two inclined surfaces that meet at their high
side to form a ridge?
Gable
A ___________ roof is designed to provide light and ventilation.
Sawtooth
What type of roof is created from triangles arranged in 3 dimensions to form
a nearly spherical surface?
Geodesic Domes
What is the best indicator that a roof is weakening?
Any indication of advanced or heavy fire development
Fireproofing can be omitted from roof supports when the roof is located more
than __________ feet above the floor in an assembly occupancy.
20
Flat roofs must be designed to support the weight of:
A few workers
Rafters may be constructed by the following types of materials:
Rafters may be constructed by the following types of materials:
Wood
Steel Beams
Steel Trusses
What makes trusses vulnerable to early failure under fire conditions?
Reduced mass of components
A ____________ truss uses a curved top chord.
Bowstring
What type of trusses are most common for pitched roofs?
Pratt
What is considered the portion of roof construction to which the roof covering
is applied?
, Roof Deck
What materials are used for construction of roof decks?
What materials are used for construction of roof decks?
Plywood
Wood Planks
Precast gypsum planks
A vapor barrier is needed when the outdoor temperature is below:
40F (50C)
What type of membrane roofing uses several overlapping layers of roofing
felt saturated with tar or asphalt?
Build Up
What is the major difference between flat and pitched roofs?
Water immediately drains from a pitched roof
What type of roof coverings are effective against a light fire exposure?
Class C - Light Fire Exposure
What types of roofs involve the use of the roof surface of a building for a
rooftop garden?
Green
What type of roof produces clean and reliable energy?
Photovoltaic (Solar Energy)
What are small structures erected on the main roof of a building?
Penthouses
True or False: Roofs are generally as strong as floors since they must endure
extensive dead loads and demanding live loads such as snowpacks and high
winds.
False
What are special dangers posed to firefighters by flat roof structures?
Flat roofs create a false sense of security for firefighters
What type of pitched roof has square ends in which the end walls of the
building form triangular areas beneath the roof?
