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  • Codes | and tools (ALT+T)
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Building sustainably

Markings

  • The standard system within the UK is also used on imports from Scandinavia, Europe, Canada and USA.
  • Softwood (within BS 4978) has two descriptions:
    GS = General Structural
    SS = Special Structural
  • Hardwoods (within BS 5756) has three descriptions:
    HS = Tropical hardwoods
    THA/THB = Temperate large sections >100mm thick
    TH1/TH2 = Temperate small sections >100mm thick.