Chapter 7- Wood Frame Construction Flashcards
Type V construction includes six types of wood frame structures.
Balloon frame Log cabins Plank and beam Platform frame Post and frame Truss frame
Plumbers are often the culprits for starting fires in the walls of __ frame buildings.
Balloon
The basement of a __ frame building is usually the worst place for a fire to start.
Balloon
Three stories are typically the limit for __ frame construction.
Platform
In a balloon frame building, there is structural continuity from top to bottom. In contrast, in the __ frame building, there is no continuity from top to bottom.
Platform
However, there is one common vertical means of fire spread in both balloon frame and platform frame buildings; the __ __. In single family homes, this is the quickest way for smoke and heat to rise to the top of the home.
Open stairwell
This type of construction has the positive benefit of reducing the volume of concealed space in which fire can burn shielded from hose streams. The interior finishes used, however, often have high flame spread and smoke developing characteristics.
Plank and beam
The empire state building weighs 23 pounds per cubic foot, whereas modern high rises weigh as little as __ pounds per cubic foot.
8
Trusses are most often used as beams, but there are many trussed columns, especially in huge buildings and special purpose structures, such as high energy transmission lines and tall radio towers. The truss satisfies many building requirements:
- __
- __
- __
- It is lighter in weight than solid construction, thus reducing the weight of supporting walls or columns.
- It provides long clear spans, thus giving maximum flexibility in the use of space.
- Many trusses, such as lightweight wood trusses and steel bar joists, can be delivered prefabricated.
Lightweight wood truss floors are a known hazard to firefighters. Not only is there the hazard of __ __, but the void is also a reservoir for explosive carbon monoxide.
Early collapse
During a fire, the presence of truss floors may be disclosed by smoke or fire pushing through the wall at the floor line (this is less likely in brick veneered building). The exterior __ plays a critical role in whether this effect is visible.
Sheathing
Wood truss roofs are just as hazardous to firefighters as lightweight truss floors. In addition to the likelihood of collapse under fire conditions, they present another hazard: they lack the __ __ that is present in legacy construction, meaning that the fire departments roof ladder hooks will hang on the roof deck sheathing rather than a beam.
Ridge pole
The flammability range of CO is from __-__ %; its ignition temperature is __ degrees F.
12.5-74%
1128 degrees F
The purpose of these systems is to prevent flashover, save lives, and permit the occupants to escape.
Automatic Sprinkler Systems
Recent tests of wood I-beams, as discussed in the chapter that reviews the features of fire protection, have shown failure in just over __ minutes in a simulated basement fire at UL, Inc.
6
Wood __ __, along with lightweight wood __, can be considered the most dangerous of all structural members to fire fighters today.
I-Joists
Trusses
Firestops typically limit __ movement through relatively small, concealed passages such as under stairs and inside walls.
Vertical
Firestopping material may consist of at least __ inch nominal lumber, two thicknesses of __ inch nominal lumber with broken up lap joints, or 23/32 inch plywood or other approved materials.
2
1
Draftstops, in contrast, limit __ movement through large concealed passages such as open web floor trusses or attics.
Horizontal
Draftstopping may consist of at least __ inch gypsum board, __ inch plywood, sheet metal or other approved materials, usually applied parallel to the main framing members.
1/2
3/8
__ firestopping is often made from the cut off ends of joints.
Wood
Also known as gasoline siding, is usually made to look like brick or stone. It is often used as replacement siding over wood. It burns readily and produces dense black smoke.
Asphalt felt siding
In a bearing wall, __ can be seen, usually every seventh row.
Headers
