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Demonstrating Fire Spread in Joist Bays and Blocking

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1:51
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Why firefighters and fire codes are important 💪 #firefighters #firecode #carpentry #building

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What happens here

A framed mock-up simulating a joist bay between two floors (labeled '1st floor Drywall' and '2nd floor DW') is used. A small fire is ignited at the base of the first floor. Without any 'blocking' material, the smoke and heat are shown to rapidly rise through the open joist bay, easily reaching the second floor. Subsequently, a piece of wood labeled 'BLOCKING' is inserted between the floors within the joist bay. When another fire is started, the blocking effectively contains the smoke and heat to the first floor, preventing its vertical spread to the upper level.

Goal: Show how fire spreads through open joist bays and the effectiveness of fire blocking

Tools and materials

  • Joist Bay Model Custom Built — To simulate the vertical space between floors in a building
  • Small Fire Source — To create smoke and heat for the demonstration
  • Wood Blocking — To demonstrate how fire is contained within a floor level

What they say

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Firefighters have to create vertical ventilation to allow the smoke to rise and clear out the space. Here's a joist bay and we have the first floor and the second floor. When there's no blocking and a fire starts on a lower level, this heat allows this to rise and come out in higher floor levels. If a fire starts and you install blocking, blocking helps contain the fire to the first floor. Another common place is your vent. If a fire starts in the basement, this can cause a fire to go up your stack and into higher floors

Auto-generated from the video audio.