BUILDING CONSTRUCTION IFSTA : Chapter 3

1. BUILDING CONSTRUCTIONIFSTA : Chapter 3

2. BUILDING CONSTRUCTIONIFSTA : Chapter 3 • Additional reading: • IFSTA Essentials #4 – chapter 8, 9, 10 • Only for the information relating to building construction • Some quiz, midterm and final questions will be from this material

3. Learning Objectives • List and define five types of building construction. • Identify the effects fire has on common building materials to enable firefighter’s to effectively attack the fire. • Identify the different occupancies and their effects at a structure fire.

4. Learning Objectives • Identify the hazards of building construction during fire suppression operations. • Identify construction features during size up. • Identify indicators of structural failure or collapse during fire suppression operations

5. Types of Building Construction • Most building codes have 5 types of building construction. • Many buildings include several types of construction.

6. Type I: Fire Resistive Construction • Structural members made of noncombustible / limited combustible materials. • Construction intended to confine fire and its byproducts to a given location. • Primary fire hazard is contents of structure.

7. Type II: Noncombustible Construction • Lower degree of fire resistance than type I. • Fire resistance rating on all exterior and interior load bearing walls. • May have combustible features, as materials with no fire resistance rating may be used. • Generally have flat roofs with combustible felt, insulation and roofing tar.

8. Why is Size-up Important?

9. Type III: Ordinary Construction • Exterior walls & structural members of noncombustible / limited combustible materials. • Interior members (walls, beams, floors, roof) are made of wood. • Hazards: smoke and fire spread through concealed spaces. • Fire stops to limit spread.

10. Type IV: Heavy Timber • Exterior / interior walls noncombustible material. • Interior structural members (beams, columns, arches, floors etc.) made of solid or laminated wood with no concealed spaces. • Found in old factories, warehouses, churches.

11. Type V: Frame Construction

12. Type V: Frame Construction • Exterior and interior structural members made of wood. • Fire Hazards: unlimited potential for fire extension, fire extension to nearby structures. • Typical residential home

14. Platform Frame

15. “Silent Flooring”

16. Poor Construction Methods

17. Fire Effects on Common Construction Materials – Wood May be used in load bearing and non-load bearing walls. Reaction of wood to fire conditions is based on the size of the wood and its moisture content. Water does not have a negative effect on wood’s structural strength. Plywood, particle board, paneling may be highly combustible, produce toxic gases and rapidly deteriorate under fire conditions.

18. Fire Effects on Common Construction Materials - Masonry • Brick, concrete, and stonework. • Commonly used for firewalls to separate connected structures and prevent fire spread. • May be used as load bearing or veneer. • Minimally affected by fire & high temperatures. • Mortar joints between bricks, blocks may deteriorate. (mortar mix is weakest part of wall) • Rapid cooling of masonry by water may cause cracking or spalling.

20. Fire Effects on Common Construction Materials - Concrete • Concrete is a mixture of portland cement, sand, gravel and water. • Often used as a fire resistive protection for structural steel (reinforced concrete). • May crack or spall if heated, indication of damage & reduced strength. • Heating may cause bond between steel and concrete to fail. • Concrete tends to absorb and retain heat.

21. Fire Effects on Common Construction Materials – Reinforced Concrete

22. Fire Effects on Common Construction Materials - Steel • Primary use of steel is for structural members. • Steel is an excellent conductor of heat. • Steel loses strength as temperature increases • Steel structural members will elongate when heated. • Water can cool steel structural members and reduce risk of failure or collapse.

23. Fire Effects on Common Construction Materials - Steel

24. Fire Effects on Common Construction Materials - Plastic • Becoming integrated to replace/improve common building materials • Plastics are oil-based (hydrocarbons) • Two general types • Thermoplastics (melt, deform, vapourize = burns!) • Thermosets (decomposes, only burns with extreme temps)

25. Fire Effects on Common Construction Materials - Plastic • General Rule of Thumb when fighting fires involving plastics… • Burn fast • Very intense heat • Dense black smoke • Extremely toxic • Can resemble a Class B Fire (flammable liquids)

27. BREAK TIME

28. Roof TypesThree Main Types:(a) Flat(b) Pitched(c) Arched

29. Occupancy Versus Type of Construction • Occupancy creates the fire load. • Building codes specify building type based on occupancy classification. • Fire code determines fire protection based on building and occupancy use. • Occupancies are residential, commercial, business, industrial and educational. • Each type has a number of hazards.

30. Occupancy Hazards

31. Building Uses • Ontario Fire Code and Ontario Building Code separate buildings in groups A-F, as related to their major use (or major occupancy) • With each type of building comes various requirements/restrictions on building construction • Private dwelling residences are exempt (with some exceptions)

32. Building Uses • A – Assembly • Theatres, libraries, schools, large bars, pubs and restaurants • B – Institutional (compelled to sleep over) • Jails, hospitals, orphanages, nursing homes • C – Residential • Apartment buildings (common area) , group homes, houses, motels • D – Business and Personal Services • Banks, barber shops, offices (medico legal), laundromat • E – Mercantile • Markets, stores, shops, supermarkets, restaurants, bars and pubs • F – Industrial • Flammable liquid plant, television studio, freight depot

33. Firefighter Hazards:Structure Fires • Change in occupancy creating an unusually heavy fire load. • Dangerous stockpiling and excessive stock creating access problems. • Unknown design errors, renovations, contractor short cuts. • Arsonists traps or tampering with fire protection systems. • Occupancy may not be what it appears. (drug lab, boarding house, group home, etc.)

34. Construction Features Assessed During Size Up What constructions features are important during size-up?

35. Construction Features Assessed During Size Up

36. Firefighter Hazards:Structure Fires • Combustible furnishings & finishes. • Wooden floors / ceilings. • Large open spaces. • Synthetic materials. • Lightweight & truss construction.

37. Lightweight Wood or Steel Truss Construction=Very Dangerous Firefighting Conditions

38. Truss Roofs

41. Bowstring Truss!

42. Beware of the Truss!

43. Structural Collapse • Every structure fire has the potential for collapse. • Firefighters must be aware and look for indicators to collapse.

44. Signs of Potential Collapse • Prolonged exposure.(time) • Distorted structural members. • Fire on floors below heavy machinery and heavy loads.

45. Signs of Potential Collapse

46. Building Collapse Zone

48. Size Up – What do you see?

49. The Back?

50. The Side?