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FVCC Fire Rescue. Ventilation Part C. CHARACTERISTICS OF ROOF TYPES. Flat Commonly found on commercial, industrial and apartment buildings May have a slight slope to it Roof may be surrounded or divided by parapets May support: Water tanks Air conditioning units Equipment Antennas
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FVCC Fire Rescue Ventilation Part C
CHARACTERISTICS OF ROOF TYPES • Flat • Commonly found on commercial, industrial and apartment buildings • May have a slight slope to it • Roof may be surrounded or divided by parapets • May support: • Water tanks • Air conditioning units • Equipment • Antennas • Other obstructions • Structural part similar to floor construction
PRECAUTIONS WHEN VENTILATING • Flat • Use roof ladder. • Look for hot spots or sagging of the roof area PRIOR to walking on surface and continually during ventilation. • Always sound roof PRIOR to walking on surface and continually during ventilation.
PRECAUTIONS WHEN VENTILATING • Look for roof additions or changes, such as overhangs, inverted flat roofs, security measures, parapet walls. • Look for obstacles and excess weights on roof, such as HVAC systems, skylights, vent pipes, other openings. • Provide two means of escape from the roof remote from each other.
PROCEDURES • Vertical • Flat roof • Determine location of opening • Location of seat of fire • Direction of wind • Existing exposures • Extent of fire • Obstructions
PROCEDURES • Locate supports by sounding with an axe. • Mark the location for opening by scratching a line on the roof with the pick head. • Remove the built up material or metal by cutting the materials and using the pick head to pull the materials out of the way. • Cut the wood decking diagonally alongside the joist towards the hole. • Pry up the roof boards with the pick end of the axe. • After opening the roof, push the blunt end of a pike pole or plaster hook through the opening to penetrate the ceiling below.
CHARACTERISTICS OF ROOF TYPES • Shed • Similar to flat except slopes from front to back • Slope may be gradual or steep
PRECAUTIONS WHEN VENTILATING • Shed • Use roof ladder • Look for hot spots or sagging of the roof area PRIOR to walking on surface and continually during ventilation. • Always sound roof PRIOR to walking on surface and continually during ventilation. • Look for roof additions or changes such as overhangs, inverted flat roofs, security measures, parapet walls. • Look for obstacles and excess weights on roof, other openings. • Provide two means of escape from the roof remote from each other.
CHARACTERISTICS OF ROOF TYPES • Pitched • Elevated in the center • Construction • Rafters • Run from ridge to top plate • Made of wood, metal or combination
PRECAUTIONS WHEN VENTILATING • Pitched • Use roof ladders • More profound incline; take extra precautions against slipping • Look for hot spots or sagging of the roof area PRIOR to walking on surface and continually during ventilation • Look for roof additions or changes such as overhangs, inverted flat roofs, security measures, parapet walls • Look for obstacles and excess weights on roof, such as HVAC systems, skylights, vent pipes, other openings. • Provide two means of escape from the roof remote from each other
PROCEDURES • Pitched roof • Determine location of opening, usually the highest point • Place a roof ladder on the roof so that personnel working off it will be upwind from the hole. • Locate supports by sounding with an axe. • Mark the location for the opening by scratching a line on the roof with the pick head • Remove the shingles or roofing sufficiently to permit the initial cut • Cut the sheathing along side a rafter, the distance required for the opening.
PROCEDURES • Opposite side is then cut in a like manner. • Remove sheathing boards with the pick of the axe • After opening the roof, push the blunt end of a pike pole or plaster hood through the opening to penetrate the ceiling below
CHARACTERISTICS OF ROOF TYPES • Sheathing • Roofing materials • Shingles • Wood • Metal • Asbestos • Composition • Tile • Slate • Pitch of roof may be gradual or steep
INTEGRITY OF A ROOF SYSTEM • Construction • Materials • Wood • Steel • Type of roof support • Rafters • Truss
INTEGRITY OF A ROOF SYSTEM • Visual observation/warning signs • “Spongy” roof • Melting asphalt • Smoke coming from roof • Fire coming from roof • Excess weight (ex. HVAC) • Elapsed time of fire • The longer the fire, the less the roof integrity.
Ventilation Considerations • High rise structures: • Stack effect: fire/smoke spread rapidly via stairways, elevator shafts, pipe shafts, air handling systems, and other vertical openings. • Smoke & other fire gases will travel through a high building until their temperatures come to equilibrium with ambient air. This is the floor you will find the maximum amount of smoke.
Ventilation Considerations • High rise structures: (cont.) • Before doors leading to the involved fire floors are opened, the door roof must be blocked opened or removed. • Ventilation in high rise buildings should be considered during pre-incident planning. • If the building has a complicated HVAC system, in order to control ventilation you should call a building engineer.
Age of Building (1921) • Over Bow String Truss • head wires • Placement of aerial (only way • this roof structure should be ventilated)
Bow string truss: can be difficult to ventilate Because lower chord of the truss may be covered With a ceiling to form an enclosed roof space. This space is called a cockloft
PRECAUTIONS WHEN VENTILATING • Arched • Be conscious of danger of sudden and total collapse. • Roof ladders useless, recommend aerial devices. • Be aware of concealed voids, such as cocklofts and attic spaces covered by ceilings.
VS 10-10 Parapet FLAT ROOF CONSTRUCTION Parapet Sheathing Bar Joist Felt Slag or Gravel Metal Deck Flat (Hung) Ceiling False (Hung) Ceiling
Flat roof most often found on commercial, industrial, and apartment buildings.
VS 10-11 PITCHED ROOF CONSTRUCTION Ceiling Joist Rafter Wall Plate Siding
Yes, this is a residence!!! So, how do you vent this person’s home? Tin roof should be sliced open with tin snips & peeled back.
Extra Bits of Important Test Stuff Balloon Frame? Basement Fire? Attic Fire? First choice in ventilating a basement fire? What might be the last resort in ventilating a structure to reduce Vertical extension during a basement fire? What is horizontal extension? Name some methods? Know your roof types! Know your roof materials!