Permissible Clear Spans for Ceiling Joists (to BS 5268-7.3)

Imposed load
0.25 kN/m²
Strength class
  • Find the column for your dead load and spacing, and the row for your timber size to find the permissible clear span in metres.
  • Click on a span to generate a full calculation (you can adjust the exact span).
  • This span table is to the format and methodology given in BS 5268-7.3.
  • These spans were calculated using our ceiling joist calculation engine.
  • These span tables are the equivalent of other industry-standard span tables and are calculated to the same standards.
  • This table uses commonly available UK regularised timber depths.
  • Read the notes at the bottom of the table for assumptions, references and related standards.
Back BACK CEILING JOIST CALCULATOR
C16
Dead load per square metre (in kN/m²) supported by joists
Not more than 0.25 More than 0.25 but not more than 0.5
Centre-to-centre spacing of joists (in mm)
Joist size
Width × depth (mm)
400 450 600 400 450 600
Permissible clear span (metres)
38 × 72 1.147 1.137 1.110 1.110 1.097 1.063
38 × 95 1.693 1.674 1.623 1.623 1.600 1.538
38 × 120 2.326 2.294 2.210 2.210 2.173 2.075
38 × 145 2.984 2.938 2.816 2.816 2.762 2.624
38 × 170 * 3.658 3.596 3.432 3.432 3.361 3.180
38 × 195 * 4.343 4.263 4.054 4.054 3.966 3.740
38 × 220 * 5.033 4.934 4.681 4.681 4.574 4.303
44 × 72 1.233 1.222 1.192 1.192 1.178 1.140
44 × 95 1.815 1.794 1.737 1.737 1.712 1.644
44 × 120 2.485 2.451 2.358 2.358 2.317 2.211
44 × 145 3.180 3.130 2.997 2.997 2.939 2.789
44 × 170 3.890 3.822 3.645 3.645 3.569 3.374
44 × 195 * 4.609 4.522 4.299 4.299 4.204 3.963
44 × 220 * 5.331 5.226 4.956 4.956 4.841 4.552
47 × 72 1.274 1.262 1.231 1.231 1.216 1.176
47 × 95 1.872 1.850 1.790 1.790 1.764 1.693
47 × 120 2.559 2.523 2.427 2.427 2.385 2.274
47 × 145 3.271 3.219 3.081 3.081 3.021 2.866
47 × 170 3.998 3.927 3.744 3.744 3.665 3.464
47 × 195 * 4.732 4.642 4.412 4.412 4.314 4.065
47 × 220 * 5.469 5.361 5.083 5.083 4.964 4.668
63 × 95 2.140 2.114 2.041 2.041 2.009 1.924
63 × 120 2.909 2.865 2.751 2.751 2.700 2.570
63 × 145 3.698 3.636 3.474 3.474 3.404 3.225
63 × 170 4.497 4.416 4.205 4.205 4.114 3.884
63 × 195 5.300 5.199 4.937 4.937 4.825 4.544
63 × 220 6.103 5.981 5.669 5.669 5.536 5.204
ALS/CLS
38 × 89 1.547 1.530 1.486 1.486 1.466 1.412
38 × 114 2.171 2.143 2.067 2.067 2.033 1.945
38 × 140 2.851 2.808 2.694 2.694 2.643 2.514
38 × 184 * 4.041 3.968 3.780 3.780 3.699 3.494
* Boarding to be fastened on top of ceiling joists with a depth to width ratio greater than 4