Find the column for your dead load and spacing and the row for your timber size to find the permissible clear span in metres.
Floor joist spans c24.
True floor joist span calculations can only be made by a structural engineer or contractor.
This means that some values are slightly more conservative than span tables from other sources if those do not include the amended guidance.
Maximum floor joist span for no.
The floor joist span tables are based on the loadings given in the amended version of bs 6399 1 which is an imposed load of either a uniformly distributed load of 1 5 kn m or a concentrated load of 1 4 kn.
Live load is weight of furniture wind snow and more.
Two additional joists required bold text normal bearing of 40mm to be doubled.
Other span tables are based on the guidance given.
Span tables for domestic floor joists to bs 5268 7 1 note.
If supporting lightweight partitions running parallel to joists provide two additional joists under each partition.
Permissible clear spans for domestic floor joists.
1 ft 0 3048 m.
Dead load weight of structure and fixed loads 10 lbs ft 2.
Imposed load not exceeding qk 1 5 kn m2 or qk 0 90 kn.
Dead load per square metre in kn m supported by joists.
1 psf lb f ft 2 47 88 n m 2.
Our floor joist span tables are based on loadings given in the newer amended version of bs 6399 1.
2 grade of douglas fir are indicated below.
Service class 1 or 2.
Span tables ceiling joists imposed load 0 25 kn m c24 timber permissible clear spans for ceiling joists to bs 5268 7 3 imposed load.
Our floor joist span tables are based on loadings given in the newer amended version of bs 6399 1.
Floor joist span tables for surveyors floor construction.
This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction.
C24 and i joists the weight of the timber floor itself consists of the timber joists the plasterboard ceiling underneath it except for suspended timber ground floors the floorboards and the nails or screws used to fix both of the aforementioned coverings.
Size of joists mm clear span c16 joist m clear span c24 joist m 47 x 95 47 x 120 47 x 145 47 x 170 47 x 195 47 x 220 1 77 2 40 2 89 3 38 3 87 4 36 2 04 2 75 3 47 4 20 4 93 5 66 floor joists flat roof joists assumptions at.
See the notes below the span tables for details.