Timber decking: the professional's manual

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Best practice guidance to ensure desired performance and deck longevity.


The definitive professional guide for decking designers and builders. Span tables enable decking specifiers to make the most efficient use of timber. Includes updated information on commercial decking, handrails and timber species.


Timber decking is often the material of choice for outdoor seating areas, and is increasingly popular for walkways and public spaces. It provides a natural, durable and aesthetically pleasing alternative to the traditional patio or terrace. Quick and easy to build, it requires less groundwork than masonry construction, while also providing a level of versatility that enables deck structures to be created on most sites.


The third edition of Timber decking enables professional designers and deck builders to utilise the advantages of timber and avoid potential pitfalls. It addresses design, both of the complete deck and of individual components, covering timber specification and selection, construction and finishing treatments.


Prepared with the assistance of BM TRADA technical consultants and the Timber Decking and Cladding Association, Timber decking now includes additional guidance and examples to help professional decking designers and builders:

  • 25 new or updated photographs and drawings
  • 18 new pages of span tables* and accompanying notes, in line with Eurocode 5 design code
  • a significantly expanded section on slip resistance, including strategies to reduce slip potential
  • further material on deck preparation and fixing details
  • extended guidance on preservative treatment and fire retardant finishes
  • more information on visual appearance grading, weathering and timber species, including modified woods.


*Span tables prepared by Dr Keerthi Ranasinghe.



  • Use of timber for decking
  • Pre-planning
  • Performance
  • Substructure
  • Deck boards
  • Superstructure
  • Construction
  • Finishing and maintenance
  • References and further reading
  • Appendix I: Timbers for decking
  • Appendix II: Span tables