1 / 57

Building Construction

6. Building Construction. Objectives (1 of 3). Describe the characteristics of the following building materials: masonry, concrete, steel, glass, gypsum board, and wood. Objectives (2 of 3).

Télécharger la présentation

Building Construction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. 6 Building Construction

  2. Objectives (1 of 3) • Describe the characteristics of the following building materials: masonry, concrete, steel, glass, gypsum board, and wood.

  3. Objectives (2 of 3) • List the characteristics of each of the following types of building construction: fire-resistive construction, noncombustible construction, ordinary construction, heavy-timber construction, and wood-frame construction.

  4. Objectives (3 of 3) • Describe the function of each of the following building components: foundations, floors, ceilings, roofs, trusses, walls, doors, windows, interior finishes, and floor coverings. • Describe how each of the five types of building construction react to fire.

  5. Introduction (1 of 2) • Building construction affects how fires grow and spread. • Fire fighters need to understand how each type of building construction reacts when exposed to the effects of heat. • Determines when it is safe to enter a burning building and when it is necessary to evacuate

  6. Introduction (2 of 2) • Occupancy • How a building is used • Classifications indicate who is likely to be inside, how many people, and what they are likely to be doing • Contents • Vary, but usually related to building use

  7. Construction Materials • Key factors affecting combustibility: • Combustibility • Thermal conductivity • Decrease of strength at elevated temperatures • Thermal expansion when heated

  8. Types of Construction Materials • Masonry • Concrete • Steel and other metals • Glass • Gypsum board • Wood • Plastics

  9. Masonry • Inherently fire-resistive • Poor conductor • Openings can allow fire to spread. • With prolonged exposure to fire, masonry can collapse.

  10. Concrete • Naturally fire-resistive • Poor conductor of heat • Strong under compression • Weak under tension • Can be damaged through exposure to fire • Spalling

  11. Steel (1 of 2) • Strongest material in common use • Strong in both compression and tension • Will rust if exposed to air and moisture • Not fire-resistive • Good conductor of heat

  12. Steel (2 of 2) • Expands and loses strength when heated • Any sign of bending, sagging, or stretching indicates immediate risk of failure.

  13. Other Metals • Aluminum • Siding, window and door frames, and roof panels • Often melts and drips in fires • Copper • Primarily used for piping and wiring • Zinc • Used as a protective coating for metals

  14. Glass • Noncombustible, but not fire-resistive • Ordinary (nontreated) glass will break when exposed to flame.

  15. Gypsum Board • Very good insulator • Limited combustibility • Paper will burn, but gypsum itself will not. • Often used as a firestop • Prolonged exposure to fire will cause failure.

  16. Wood • Most common building material • Highly combustible • Weakens when heated • Fire-retardant chemicals can weaken wood.

  17. Plastics • Rarely used for structural support • Combustibility varies • Many plastics release dense, toxic smoke when they burn. • Thermoplastic materials melt and drip. • Thermoset materials lose strength but will not melt.

  18. Types of Construction • Type I: Fire-resistive • Type II: Noncombustible • Type III: Ordinary • Type IV: Heavy timber • Type V: Wood frame

  19. Type I: Fire-Resistive (1 of 2) • All structural components must be noncombustible. • Used for: • Large numbers of people • Tall or large area • Special occupancies

  20. Type I: Fire-Resistive (2 of 2) • Building materials should not provide fuel for a fire. • Steel framing must be protected. • Fires can be very hot and hard to ventilate. • In extreme conditions Type I buildings can collapse.

  21. Type II: Noncombustible (1 of 2) • All structural components must be noncombustible. • Fire-resistive requirements are less stringent than Type I.

  22. Type II: Noncombustible (2 of 2) • Structural components contribute little or no fuel. • Fire severity is determined by contents. • Most common in single-story warehouses or factories

  23. Type III: Ordinary (1 of 2) • Used in a wide range of buildings • Masonry exterior walls support floors and roof. • Usually limited to no more than four stories • Limited fire-resistance requirements

  24. Type III: Ordinary (2 of 2) • Two separate fire loads: • Contents • Construction materials • Fire resistance depends on building age and local building codes. • Exterior walls, floors, and roof are connected.

  25. Type IV: Heavy Timber (1 of 2) • Exterior masonry walls • Interior structural elements, floors, and roof of wood

  26. Type IV: Heavy Timber (2 of 2) • No concealed spaces or voids • Used for buildings as tall as eight stories • Open spaces suitable for manufacturing and storage • New Type IV construction is rare.

  27. Type V: Wood Frame (1 of 3) • Most common type of construction in use • All major components are wood or other combustible materials.

  28. Type V: Wood Frame (2 of 3) • Used in buildings of up to four stories • Wooden I-beams and trusses • Just strong enough to carry required load • No built-in safety margin • Collapse early and suddenly

  29. Type V: Wood Frame (3 of 3) • Balloon-frame construction • Exterior walls assembled with continuous wood studs. • Platform-frame construction • Exterior wall studs not continuous.

  30. Building Components • Foundation • Floors and ceilings • Roofs • Trusses • Walls • Doors and windows • Interior finishes and floor coverings

  31. Foundation • Transfer the weight of the building and its components to the ground • Ensures building is firmly planted • Weak or shifting foundations can cause collapse.

  32. Floors and Ceilings (1 of 2) • Fire-resistive floors • Floor–ceiling system designed to prevent vertical fire spread • If space above ceiling is not partitioned or sprinklered, fire can quickly extend horizontally across a large area.

  33. Floors and Ceilings (2 of 2) • Wood-supported floors • Heavy-timber floors can often contain a fire for an hour or more. • Conventional wood flooring burns readily and can fail in as little as 20 minutes. • Modern, lightweight wood I-beams and trusses

  34. Roofs • Not designed to be as strong as floors • Three primary designs: • Pitched roofs • Curved roofs • Flat roofs

  35. Pitched Roofs • Sloped or inclined • Can be gable, hip, mansard, gambrel, or lean-to • Usually supported by rafters or trusses • Require some sort of roof covering

  36. Curved Roofs • Used for large buildings that require large, open interiors • Usually supported by bowstring trusses or arches

  37. Flat Roofs (1 of 2) • Have a slight slope for drainage • Wood support structures use solid wood beams and joists.

  38. Flat Roofs (2 of 2) • Open-web steel trusses (bar joists) often used for support • Most coverings highly combustible • Ventilation may involve cutting through many layers of roofing.

  39. Trusses (1 of 2) • Triangular geometry creates a strong, rigid structure. • Usually prefabricated wood or steel • Three types: • Parallel chord • Pitched chord • Bowstring

  40. Trusses (2 of 2)

  41. Walls • Most visible part of a building • Constructed of a variety of materials • Walls are: • Load-bearing • Nonbearing • Specialized

  42. Load-Bearing Walls • Provide structural support • Either interior or exterior • Support both “dead load” and “live load” • Damaged wall can result in collapse.

  43. Nonbearing Walls • Support only their own weight • Can be breached or removed without compromising structural integrity • Either interior or exterior

  44. Specialized Walls (1 of 2) • Party walls • Common to two properties • Almost always load-bearing • Often a fire wall • Fire walls • Designed to limit horizontal fire spread • Extend from foundation through roof • Constructed of fire-resistant materials

  45. Specialized Walls (2 of 2) • Fire partitions • Interior walls that extend from a floor to underside of floor above • Fire enclosures • Fire-rated assemblies for vertical openings • Curtain walls • Nonbearing exterior walls attached to the outside of a building

  46. Doors • Can be used for entry, exit, light, and ventilation • Mostly constructed of wood or metal • Hollow-core wood doors offer little fire resistance. • Solid-core doors provide some fire resistance. • Metal doors more durable and fire resistant.

  47. Window Assemblies • Used for light, ventilation, entry, and exit • Window type depends on a variety of factors.

  48. Fire Doors and Fire Windows(1 of 3) • Constructed to prevent the spread of flames, heat, and smoke • Must meet NFPA 80 • Labeled according to approved use

  49. Fire Doors and Fire Windows(2 of 3) • Class A • Class B • Class C • Class D • Class E

  50. Fire Doors and Fire Windows(3 of 3) • Fire windows are used when a window is needed in a required fire-resistant wall.

More Related