Chapter 6 Building Construction Flashcards
Occupancy
refers to how a building is used, how many people are in there, helps determine hazards and situations encountered
Contents
amount of possible fuel in building
Types of construction materials
- Masonry
- Concrete
- Steel
- Glass
- Other metals- zinc, aluminum, copper
- Gypsum Board
- Wood
- Plastics
Key factors that affect the behavior of each construction material
- Combustibility- whether or not a material will burn
2. Thermal conductivity- Characteristic describes how readily a material will conduct heat
Steel elongate at what rate
1 inch per 10 ft at a rate of 1000 degrees
Masonry
stones, concrete blocks and brick are inherently fire resistive used to construct fire walls
Concrete
like masonry concrete is a naturally fire resistive material, does not burn or conduct well
Spalling
when steam expands it creates internal pressure that can cause sections of concrete to break off
Steel
the strongest building material in common use but is not fire resistive and conducts well. Strong in tension and compression used as structural frame work any signs of bending and sagging is a sign of structural collapse exit immediately
Other Metals
aluminum, copper and zinc used for windows doors, wiring and coating
Glass
used in windows, doors sky lights and sometimes walls. glass is non combustible
- ordinary glass breaks under heat
- Tempered glass is much stronger more difficult to break
- Laminated glass cracks and remains in place under heat.
- Glass blocks have limited strength but they can usually withstand fire.
- Wired glass is tempered glass with a metal wire mesh. this prevents the glass from breaking under heat used to prevent fire spread
Gypsum Board
also called dry wall, sheetrock, or plaster is commonly used to cover the interior walls and ceilings of residential living areas and commercial. limited combustibility. used as fire stop
Wood solid lumber
most commonly used material, is squared and cut into uniform lengths
Laminated wood
individual pieces of wood glued together. produce beams that are longer and stronger and manufactured curved beams
Wood Panels
are produced by glueing together thin sheets of wood. ex ply wood OSB
Wood Trusses don’t trust the truss
assemblies of pieces of wood or wood and metal combinations made to support roofs and floors limited material for heavy load
Wooden Beams
Efficient load bearing members assembled from individual wood components.
Rate at which wood ignites, burns and decomposes depends on sever factors
- ignition
- Moisture
- Density
- Preheating- the more it preheats the faster it ignites
- Size and form- surface area logs and sticks
Plastics
synthetic materials usually petroleum based
Thermoplastic materials
melt and drip when exposed to high temps, even those as low as 500 degrees. rapidly spreads fires
Thermoset materials
are fused by heat and will not melt as the plastic burns although their strength will decrease dramatically
Standard on Types of Building Construction
NFPA 220
Type I Construction
(Fire Resistive) concrete and steel beams, load bearing walls 3-4 hours some floors 2 hours resistance, large occupancy buildings schools, hospitals, and high rise buildings, parking structures
Type II Construction
(Non Combustible) must be made of noncombustible materials. 1-2 hours
Single story warehouse or factory buildings, concrete floors, concrete block walls steel frame and metal roofing (sprinklers)
Type III Construction
(Ordinary) Look out for hot spots and fire spread 1-2 hour fire resistance, 4-6 story buildings ex. strip malls and apartments. Made of masonry exterior walls made of wood and plaster/gypsum. Materials used to build and individuals contents fuel fires