Staircases

6.6.12Timber and wood-based products

Staircases shall use timber and wood-based materials of sufficient quality and durability.

Timber for joinery should:

  • comply with BS 1186 : Part 1
  • be class 3 or better
  • be free of resinous knots, splits, shakes and wanes.

The following should meet BS 1186 : Part 2:

  • fits of joints
  • construction of joints
  • moving parts
  • gluing
  • laminating
  • construction of finger joints
  • surface finish.

Materials should be in accordance with the guidance given in Table 4.

Table 4: Materials for staircases

MaterialRequirements
Plywood – should be used for risers onlyBS EN 636
ChipboardBS EN 312 Type 5
Oriented strand boardBS EN 300 OSB3
Fibre building boardsBS 1142 : Part 2
Glued laminated timber structural membersBS 4169

Timber which is to be exposed to the weather should be:

  • naturally durable, or
  • pretreated with preservative against fungal attack in accordance with Chapter 3.3 ‘Timber preservation’.