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Introduction to Alternative Building Materials Jason Brooks Firefighter/Paramedic Chagrin Falls Fire Department
Objectives • To gain awareness of different types of building materials • To learn how and where these materials may be used • Gain knowledge valuable on a fireground to protect ourselves • Learn the limitations of some of these materials
Topics Discussed • • • Lightweight Wood Trusses Structural Insulated Panels – SIPs Insulated Concrete Forms – ICFs Laminated Veneer Lumber – LVL Laminated Strand Lumber – LSL Glue Laminated Beams – Glulam I-Joists Hi-Impact Wallboard Hi-Impact/Hurricane Windows
Lightweight Wood Trusses • Prior to the 1940’s, primarily made of steel • Wood trusses were developed during World War II • Originally used wooden gusset plates that were nailed and glued together • Metal gusset plates with nail holes were developed to speed up manufacturing around 1952 • Current gusset plates are punched steel that is pressed into place, teeth only go 1/8” into wood
Lightweight Wood Trusses The Truss Roof Industry Says: Approximately 80% of homes built today use metal plate connected wood trusses in the floor, roof or both. Metal plate connected wood trusses have been successfully used since the mid-1950’s …their long span capacity often eliminates the need for interior beams, columns or footings The tension web system utilizes an open web design, which permits heating ducts, electric wiring and plumbing to be easily run through the trusses.
Lightweight Wood Trusses • Incorrectly assembled trusses • Gusset plates are not squarely on joints • This is the same attic space • Notice jobsite truss correction • Is this code?
Gusset Plate Installation
How do gusset plates act in a fire situation? Are you sure?
Truss Fire Test
Various Truss Designs
BEWARE OF "TRUSS 2000" These trusses are finger jointed and glued into place. What is not in the picture is that the spans can be done the same way and extended indefinitely. It is scary. Firefighters/Inspectors are finding it in lots of new lightweight construction. As "The Old Professor“, Francis Brannigan, has told us for years: BEWARE THE TRUSS!
Structural Insulated Panels • • • Structural Insulated Panels – SIPS First introduced around 1934 Sandwich construction – OSB and rigid foam insulation • Combines construction steps • Fast installation
Structural Insulated Panels SIPs are highperformance building panels for floors, walls and roofs in residential and commercial buildings. Each panel is typically made using expanded polystyrene (EPS), or polyisocyanurate rigid foam insulation sandwiched between two structural skins of oriented strand board (OSB).
Structural Insulated Panels Due to the nature of the material, SIP’s are good for fire stopping. No void spaces in walls No air to fuel fire in walls No drop down spaces Insulation will melt, not burn when in contact with a flame.
Structural Insulated Panels
Structural Insulated Panels
Insulated Concrete Forms • First introduced in Canada in 1966 • Hollow blocks made of rigid foam that are erected and filled with concrete • Much faster installation than block construction • Less chance of leakage, fewer seams
Insulated Concrete Forms • Entire wall structure placed in ground • Sections are glued together • Concrete is pumped into forms • Forms stay permanently as part of the walls
Insulated Concrete Forms • Corners are tied together with plastic brackets • Plastic strapping keeps wall parallel
Insulated Concrete Forms • No wooden studs used • No concrete block used • Paneling can be glued to forms • Reinforced sites are as strong as studs for anchoring
Laminated Veneer Lumber - LVL • • • First used during WWII to make propellers Used since the early 1970’s for beams Resists shrinking, warping, splitting and checking • High bending and shear strength • Veneers are vertically oriented
Laminated Veneer Lumber - LVL • High strength-to-width ratio; more than 50% stronger than solid sawn products. • Environmentally friendly – Veneer technology converts about 50% more of the log into usable product than methods that produce solid sawn products. • Ordinary nail assembly.
Laminated Veneer Lumber - LVL • Primary applications are Floor Beams, Window and Door Headers, Ridge and Hip Beams • Made in same sizes as dimensional lumber • Made up to 64’ long
Laminated Strand Lumber • Typically, when lumber is delivered to the jobsite, it has a moisture content of 19%. Over time, it dries into balance with the air moisture in the home, usually about 10%. • LSL is engineered to about 9% moisture content, which means greater resistance to shrinking, twisting, popping or deforming.
Laminated Strand Lumber • • • Stronger and straighter than lumber Consistent dimensions Same uses as LVL
Glue Laminated Beam - Glulam • • • Laminated lumber, similar to LVL Lighter than LVL or steel Comes in standard lumber dimensions Listed as heavy timber in fire code Uses dimensional lumber for each layer
I-Joists • First introduced in 1981 • Made of two primary components – Flanges – Webs • Flanges are generally manufactured from sawn lumber or structural composite lumber • Webs typically consist of plywood or oriented strand board
I-Joists Joined together with joist hangers
I-Joists • Wires and pipes significantly reduce the strength of the IJoist • Manufacturers require holes to be made perfectly round to allow even distribution of weight on the I-Joist
I-Joists This is an example of a commercially made stiffener to brace I-Joists that have had holes cut into them
I-Joists Notice the floor is still in place even though the I-Joists have been completely destroyed by fire!
I-Joist in Transport
Hi-Impact Wallboard • • • First introduced in the late 1990’s Gypsum board with lexan backing Available with several different thicknesses of Lexan • Looks like regular drywall when installed
Hi-Impact Wallboard • The Roberts Park (IL) FD performed a breeching test to determine what tools would work • Object to make a hole large enough for a firefighter to escape • The firefighter was positioned on his knees, to stay low, to simulate being in a fire condition
Hi-Impact Wallboard • Tools used/tried: – – – 8 lb. Maul 8 lb. Pick-head axe 8 lb. Flat-head axe 12 lb. Sledgehammer Halligan bar 4’ x 8’ Gypsum Hi-Impact 8000 brand Fire-shield Gypsum Wallboard screwed to 2”x 4” studs, 16” OC
Hi-Impact Wallboard Breech Test Results • • • How effective do you think the tools were? What tools were the most effective? What tools were the fastest? • Remember: These were fresh firefighters, not tired from a real fire trying to escape!
Hi-Impact Wallboard Breech Test
Hi-Impact Wallboard Breech Test Results • 8 LB Maul – Striking end used – Total blows • 14 Unable to breech wall!
Hi-Impact Wallboard Breech Test Results • 12 LB Sledgehammer – Total blows • 14 Did not breach wallboard! Broke wall stud!
Hi-Impact Wallboard Breech Test Results • 8 LB Pickhead Axe – Blade side used – Total blows • 38 Penetrated wall on 6 th swing Created hole large enough for firefighter
Hi-Impact Wallboard Breech Test Results • Halligan Bar – ADZ end used – Total blows • 30 Penetrated wall on 4 th swing Created hole large enough for firefighter
Hi-Impact Wallboard Breech Test Results • 8 LB Flathead Axe – Striking side used – Total blows • 18 Unable to breech wall!
Hi-Impact Wallboard Breech Test Results • 8 LB Maul – Cutting end used – Total blows • 19 Penetrated wall and broke a wall stud
Hi-Impact Wallboard Breech Test Conclusions • All of the striking tools were proven ineffective in breaching the Hi-Impact 8000 Wallboard. • The cutting tools proved to be most effective, usually penetrating the Lexan in less than 10 swings • The Lexan did not break easily after being struck but it did crack enough to become pliable enough to bend while the firefighter crawled through the hole
Hi-Impact Wallboard Breech Test Conclusions • One thing to consider while you are crawling through the wall, is the Lexan had tendency to get caught up on personal protective equipment and will possibly cut or rip the PPE with the sharp edges • Another consideration, is the amount of time it took to create a hole large enough to accommodate a firefighter’s size. If fire conditions are deteriorating, the firefighter is already at increased risk
Hi-Impact Wallboard Breech Test Conclusions • This test was performed with the Hi-Impact 8000 Wallboard on only 1 side of the stud • Chances are, if this product is encountered, it will be mounted to both sides of the studs, therefore at least doubling the amount of time and effort to breach the wall in an emergency situation
Hi-Impact Wallboard Burn Test • The Roberts Park (IL) FD performed a burn test to see how this material would react • The test was conducted by igniting approximately 4 pieces of packing paper inside a 4’ x 4’ simulated wall. The paper simulated any burning materials that could fall inside the wall during a structure fire • The wall was constructed using 2 – 4’ x 4’ sections of Hi-Impact 8000 wallboard mounted to metal stud framing on 16” centers
Hi-Impact Wallboard Burn Test • 4’ x 4’ wall with metal stud framing and both sides of the wall • Approximately 4 pieces of white packing paper were ignited inside the wall to simulate burning materials that have dropped into the wall during a structure fire
Hi-Impact Wallboard Burn Test The wall was placed in an upright position on a flat surface. A hole on one of the end studs was enlarged to be able to position the paper inside the wall. This could also simulate any alterations to the studs by construction personnel. Also 4 holes were placed in the top rail of the wall to simulate any pipe or electrical chases that may be added by construction personnel. The paper, approximately 4 pieces, was placed in the wall and ignited using an ordinary lighter. The fire was allowed to burn inside the wall for approximately 20 minutes from the point of ignition. At the end of the burning period, the fire was extinguished using a 5 -gallon pump can, through the holes in the metal studs. After the fire was extinguished, one side of the Hi-Impact 8000 Wallboard was removed to evaluate how the wallboard reacted to the fire
Hi-Impact Wallboard Burn Test
Hi-Impact Wallboard Burn Test • At 2 minutes, smoke changed from white to black • At 4 minutes the Lexan backing started to burn creating heavy black-grey smoke • At 6 minutes, heavy fire was coming from bay of ignition • After 1 minute of heavy fire, smoke changed to black and pink
Hi-Impact Wallboard Burn Test • Melted Lexan was noted coming from bottom of wall assembly • Fire was extinguished easily with a 5 gallon pump sprayer • One side of the wall was dismantled for inspection
Hi-Impact Wallboard Burn Test • The fire completely consumed 1 full bay of the Lexan backing between the stud spaces where the fire was started • The fire then traveled through the pipe chases in the stud to the next bay, consuming the top ½ of the 2 nd stud space
Hi-Impact Wallboard Burn Test • It was demonstrated that the Lexan backing contributed to the fire spread within the wall • The Lexan backing also created a heavy and multiple colored smoke condition during the burn phase of the test
Hi-Impact Windows • First introduced around 1970 • Now mandatory for all new construction in Miami-Dade and Broward Counties • Legislation is being drafted for all new construction in Florida • After January 1, 2007, Massachusetts law • Available locally
Hi-Impact Windows • In the Large Missile Impact Test, a window is subjected to two impacts by a nine-pound 2 x 4 beam traveling at a speed of 50 feet per second. Then this "impacted" window is subjected to hurricane-force winds. The polyvinylbutyral interlayer keeps the window intact and sealed against wind even if glass is cracked by a flying object.
Hi-Impact Windows • How are we going to breech these windows? • What are we going to do if/when we find these windows? • What are we going to do if we need to rapidly extricate someone out of one of these?
THINK: RISK / BENEFIT Risk a lot to save a life. Risk a little to save a little. Risk nothing to save nothing. EVERYBODY GOES HOME!
Special thanks to the people below. Without their help, this project would not have been possible. • Ric Jorge – Palm Beach County Fire/Rescue • Sean Murphy – Roberts Park (IL) FD • Cara Dohnalek – PGT Industries • Steve Yoder – WTCA Ohio Chapter • Todd Pallotta – Stark Truss