BUILDING CONSTRUCTION Understanding Construction Types Part Two

1. BUILDING CONSTRUCTION Understanding Construction Types Part Two

2. Review of Part One

3. Codes • In New York State, building construction, heating plants, HVAC, etc., are regulated by the following; • The Building Code • The Existing Building Code • The Fire Code • The Fuel and Gas Code • The Mechanical Code • The Plumbing Code • The Residential Code • The Energy Conservation Code

4. also Reference Standards (NFPA, ANSI, ASME, etc..) • Additionally, we also have to comply with; • NYS approved “more restrictive” local codes (i.e., county, town, city, village) • These codes provide minimum requirements. • As with all codes, there are exceptions, such as, the NYS Building Code does not apply to detached one-and two-family dwellings and multiple single-family dwelling (townhouses) not more than three stories in height with separate means of egress. These buildings fall under the Residential Code of New York State.

5. Why Know BuildingConstruction

6. WHY KNOW BUILDING CONSTRUCTION? • To alert you to potential construction hazards, • To enable a safe and effective fire attack, • By knowing basic building construction types, we can approximate how fire will spread and allow us to extinguish it quickly, • “The building is your enemy… know your enemy” Francis L. Brannigan.

7. There are TWO basic types of construction: “It either burns (combustible) or it does not burn (noncombustible)” • All buildings in the US are constructed by one of the five construction categories; • Type “1” - Fire Resistive – Least Combustible • Type “2” - Non-Combustible • Type “3” - Ordinary • Type “4” - Heavy Timber • Type “5” - Wood Frame – Most Combustible • Four of the five types have subgroups “A” & “B”.

8. Subgroups

9. Subgroup “A” • Means Protected; • all structural members have an additional fire rated coating or cover by means of sheetrock, spray on, or other approved method, • the additional fire rated coating or cover extends the fire resistance of the structural members by at least 1 hour.

10. Subgroup "B" • Means Unprotected; • all structural members have no additional fire rated coating or cover, • exposed members are only fire resistant according to their natural ability, characteristics, and fire rating.

11. TYPE “3” - Ordinary STRUCTURAL CHARACTERISTICS AND HAZARDS

12. STRUCTURAL CHARACTERISTICS AND HAZARDS Type “3”- (A) (protected) – Ordinary (ISO Class 2) (#211, NFPA 5000 “Building & Safety Code”) • structural frame, columns, etc. - 1 hour rating • exterior bearing walls – 2 hour rated • interior bearing walls – 1 hour rated • floor construction, beams and joists – 1 hour rated • roof construction, beams and joists – 1 hour rated 2010 New York State Building Code

13. STRUCTURAL CHARACTERISTICS AND HAZARDS Type “3”- (B) (unprotected) – Ordinary (ISO Class 2) (#200, NFPA 5000 “Building & Safety Code”) • structural frame, columns, etc. - 0 hour rating • exterior bearing walls – 2 hour rated • interior bearing walls – 0 hour rated • floor construction, beams and joists – 0 hour rated • roof construction, beams and joists – 0 hour rated 2010 New York State Building Code

14. Design

15. TYPE “3” - Ordinary • Characteristics; • predominate and common construction type, • also know as “brick and joist” structure, (common terms “Main Street, USA” or “Downtown, USA” and “Taxpayer” • exterior load bearing walls are of masonry and some or all other structural components are combustible (wood), • masonry walls can be brick, stone, or concrete block and terra cotta block in some older buildings, • interior structural members almost all wood, • wood used has smaller dimensions than Type “IV”.

16. Type 3 Construction • normally used for larger, sometimes multi-story, commercial or multi-family structures, • has also been used for one and two family buildings, • if floor and roof construction and their supports and all openings through floors (stairwells) are enclosed with one-hour fire resistive materials, the construction is classified as “Protected”, • generally built no higher than 6 to 8 stories, most are 2 to 4 stories high, • typically wall thickness range from 6” to 30”,

17. TYPE “3” - Ordinary • rarely protected by a sprinkler system, • many have been remodeled and altered, • roof often similar to floor construction, • hazards reduced by using fire-stops, • unstable under fire conditions, • highly damageable buildings, • primary fire hazard - fire and smoke spread through concealed spaces, • fire load – construction materials and contents,

18. Type 3 Construction • typically will have two load-bearing walls (long walls) and two curtain walls (short walls).

19. One & Two Family Residential Type “3” building

20. Type “3” Multiple Residence

21. Type “3” Commercial and Residential

22. Two story commercial Type “3” building

23. TYPE “3” - Ordinary • Type “3” buildings have been constructed in two distinct types; • Older – late 19th and early 20th century and, • Newer. • “Older” buildings; • tongue and grove floor boards, • solid lumber joists and rafters ( can be 3” x 10”), • columns could be added for additional support • room size limited by span of supporting element,

24. TYPE “3” - Ordinary • floor joists commonly have a “fire cut” on each end to keep floor joists from pushing the wall down, • 1” to 1 ½” wooden planks commonly used in the roof assembly.

25. TYPE “3” - Ordinary • “Newer” buildings; • flooring may consist of plywood, oriented strand board (OSB), • laminated veneer lumber (LVL), and parallel strand lumber (PSL), supported by • lightweight wooden trusses, and wooden I- beams, • these supports are more likely to collapse sooner than larger solid lumber joists, • roof construction using lightweight materials.

26. Hazards Relating to Type 3 Construction

27. Hazards Related to Type 3 Construction • Stability of masonry walls, • Stability of interior column, girder and beam system, • Void spaces, • Excessive fire loads, “dead” loads (HVAC, Solar Arrays) • Bow string truss roof, • Alterations can have an effect on the building, • The largest concealed space is the “Cockloft”, an open space for fire and smoke spread, • Braced Wall Spreaders- danger – wall can be out of alignment.

28. Solar Arrays and HVAC Units

29. A basic sign that a wall is in distress Braced Walls Braces of unprotected steel or cable will fail at fire temperatures

30. Arrows mark locations where star-shaped anchor plates were located on the west-side of the theater building that was adjacent to the fire building. The anchor plates appear to have been attached to the ends of the heavy timber roof trusses supporting the roof and also to some of the second-floor joists. NIOSH F2011-15

31. Photo shows star-shaped anchor plates located on the D-side wall in the area that collapsed. NIOSH F2011-15

32. Photo shows star-shaped anchor plate attached to end of floor joist. Photo shows star-shaped anchor plate attached to end of heavy timber roof truss.

33. Type “3” Bowstring truss roof

34. Collapse scene as viewed from building rear facing building front. Note portion of bowstring truss leaning against wall at right side of photo. (Photo courtesy of fire department)NIOSH F2010-38

35. Photo shows the wall that supported western end of the bowstring truss roof. The two arrows indicate the truss-end pockets in the brick masonry wall at the top of the brick pilasters where the ends of the two bowstring trusses rested. The roof was supported in the middle by the two bowstring trusses while the north and south ends were supported by the front and rear non-load bearing walls. The line indicates the approximate curvature of the roof. (NIOSH photo F2010-38)

36. NIOSH F2009-21 Photo

37. TYPE “4” – Heavy Timber • STRUCTURAL CHARACTERISTICS AND HAZARDS

38. STRUCTURAL CHARACTERISTICS AND HAZARDS Type “4” - Heavy Timber (ISO Class 2) (#2HH, NFPA 5000 “Building & Safety Code”) • structural frame, columns, etc. – heavy timber • exterior bearing walls – 1 hour heavy timber • interior bearing walls – 2 hour rated • floor construction, beams and joists – heavy timber • roof construction, beams and joists – heavy timber 2010 New York State Building Code

39. Type “4” - Heavy Timber • Characteristics; • heavy timber construction is one of the oldest types of buildings used in this country, • heavy timber buildings were originally designed and used as multi-story industrial or storage occupancies, • fire resistance is attained by placing limitations of minimum sizes on wood structural members and minimum thickness and composition of wood floors and roofs,

40. Type “4” - Heavy Timber • will have four bearing exterior walls, • construction includes columns not less than 8” thick in any dimension, • beams and girders not less than 6” x 10”, • roof framing is not less than 6” wide x 8” depth, • floors and roofs have thicker than normal construction consisting of varying layers of materials that build up to a deck of 3” thick to 4” wide, • arches and trusses not less than 8” thick in any dimension.

41. TYPE “4” - Heavy Timber • usage of approved fastenings and adhesives, • lumber may be sawn or laminated, • usually found in very old mills, factories, and warehouse, and in older churches, • exterior walls are noncombustible, • interior structures made of solid or laminated wood with no concealed spaces, • does not have plaster walls & ceilings covering interior framework,

42. TYPE “4” - Heavy Timber • wood has large dimensions, much heavier, more difficult to ignite, can withstand fire for longer time frames, • primary fire hazard - combustible contents of structural members, • does not fail early in a fire, • because of massive amount of combustible materials there will be serious heat given off and may pose exposure protection problems,

43. Heavy Timber Frame building

44. Heavy Timber columns, beams & girders

45. Masonry walls

46. Large open spaces, lack of hidden voids

48. Hazards Relating to Type 3 & 4 Construction

49. Hazards Related to Construction • Heavy fire loading, • Combustible finishes and furnishings, • Wooden floors/ceilings and coverings, • Large open spaces, • Unprotected openings

50. Hazards Related to Construction • Heavy content loading; • combustibles stored in high piles next to each other, • usually found in commercial and storage facilities, • this may override sprinkler system and provide access problems, • proper inspection and enforcement effective in these types of facilities.