Building Construction Chapter 11

What makes it difficult to determine the extent of overhead fires in roofs?

Inherent concealed spaces between the ceiling and roof deck

Why are roofs not as strong as floors?

They support lighter live loads

What safety issue arises from loads being added to roofs for which they were not designed?

Structural instability due to added loads

Why can it be difficult for firefighters to determine the extent of fire in a roof?

Multiple layers of roofing materials can conceal the extent of the fire. Signup and view all the answers

What is the slope range for low slope roofs?

0/12 to 3/12 Signup and view all the answers

Which type of roof presents a major hazard to firefighters due to steepness and lack of secure footing?

Pitched roofs Signup and view all the answers

What determines the design of pitched roofs?

Climate, function, and aesthetic considerations Signup and view all the answers

What type of roof slopes in four directions and has a degree of slope like a gable roof?

Hip roof Signup and view all the answers

Which type of roof has a break in the slope of the roof on all four sides, creating a concealed space for fire travel?

Mansard roof Signup and view all the answers

What type of roof is used to provide light and ventilation, with a raised central section containing openable windows?

Sawtooth roof Signup and view all the answers

What is the purpose of a dormer in buildings with pitched roofs?

Increase available living space in the attic Signup and view all the answers

What type of roof uses inverted trusses and creates a concealed space between the ceiling and the roof deck?

Inverted roof Signup and view all the answers

Which type of roof can fail quickly in a fire, depending on fuel load?

Unprotected lightweight open-web joist roof Signup and view all the answers

What is omitted in a type I structure from roof supports when the roof is located more than 20 feet above the floor in an assembly occupancy?

Fireproofing Signup and view all the answers

What are the conventional framing components for roofs?

Rafters, ridge boards, collar ties, ceiling joists, rafter ties Signup and view all the answers

What is required if an architect wants to leave the underside of the roof exposed without joists?

A structural ridge beam Signup and view all the answers

Which type of truss is most commonly used for pitched roofs?

Fink and Patt trusses Signup and view all the answers

What material is frequently used for both the deck and the exterior roof covering in roof construction?

Corrugated steel decking Signup and view all the answers

What is the range of gauge for corrugated steel used for decking?

29 gauge to 12 gauge Signup and view all the answers

What is the usual thickness of wood panel decking on supports 24 inches from center?

1/2 inch Signup and view all the answers

Why are the same structural systems for the roof and the floors used in a multi-story building?

Because it reduces construction costs and simplifies the overall design. Signup and view all the answers

What is the primary concern with encountering layered roofs during firefighting operations?

Extra thickness impeding progress during ventilation and access operations Signup and view all the answers

What is the purpose of a vapor barrier in a flat roof assembly?

To reduce the diffusion of interior moisture into the insulation layer Signup and view all the answers

Which type of membrane uses several overlapping layers of roofing felt saturated with a bituminous material?

Built-up membrane Signup and view all the answers

What is the function of thermal insulation in a roof assembly?

To reduce heat loss through the roof Signup and view all the answers

In what way is a fluid-applied membrane different from other types of roofing membranes?

It is applied as a liquid and then allowed to cure Signup and view all the answers

Why are wood shingles prohibited in many jurisdictions?

The base material is not fire resistant Signup and view all the answers

What is the primary advantage of using small-sized shingles and tiles on a roof?

Allowing for movement between individual units caused by thermal expansion and shifting of building structural units Signup and view all the answers

What is the life expectancy of slate as a roofing material?

150 years Signup and view all the answers

Which material is frequently made to look like clay, slate, or wood for roofing purposes?

Concrete Signup and view all the answers

What operational problem can arise with clay, slate, and cement tiles during a fire?

Becoming more slippery and posing a fall hazard Signup and view all the answers

What test procedures are materials subject to in order to be a third party listed product?

Intermittent flame exposure, burning brand, flying brand, rain, weathering, spread of flame Signup and view all the answers

What are the three classifications based on the severity of fire a material can withstand?

Class A effective against severe fire exposure, Class B effective against moderate fire exposure, Class C effective against light fire exposure Signup and view all the answers

What are the reasons rain roofs may be installed for?

To cover deteriorated roofing elements, to change the profile of a building, to update architectural design/appearance, cost effective compared to replacing roof Signup and view all the answers

What is a potential hazard for firefighters when encountering rain roofs?

Difficulty in detecting, accessing, and extinguishing products of combustion in the void space Signup and view all the answers

What is a characteristic of a photovoltaic system?

Produces reliable, clean energy for various applications including building systems Signup and view all the answers

What parameters do codes and authorities add for solar panels on buildings?

Clear space along edges and ridge of roof, uniform labeling of structures with PV related materials Signup and view all the answers

What is a potential danger related to compromised solar systems on buildings?

Can transfer electrical charge to metal roofing materials Signup and view all the answers

What is the primary hazard of vegetative roofs if not properly hydrated or if fertilizer is not stored properly?

Increased fire load Signup and view all the answers

What is the range of dead load that a rooftop garden can constitute on the roof structural system?

20-150 lbs per square foot Signup and view all the answers

What are some benefits of green roofs?

Added insulation and improved air quality Signup and view all the answers