Heavy Timber Construction

ISO classifies the building as heavy timber construction if it meets these requirements:

  • walls of masonry construction
  • floors of three inch wood plank or four inch laminated plank, both surfaced with one inch flooring
  • roof of two inch wood plank, three inch laminated plank, or 1-1/8 inch tongue-and-groove plywood deck
  • wood column supports not less than eight inch x eight inch, wood beams or girders not less than six inch x six inch, or protected metal