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.
Triple joist timber floor section.
1 psf lb f ft 2 47 88 n m 2.
Most floor joists consist of 2 by 6 inch lumber but they can use 2 by 8 or 2 by 10 as well which will require longer joist hangers.
Follow the rules to keep your floor solid.
D o u b l e j o i s t t i m b e r f l o o rs 3 1 8m to 2 4m3 6 to 7 5m 300mm binders bridging joist 300 mm c c plan.
Live load is weight of furniture wind snow and more.
This is the simplest type of timber floor used for residential buildings where spans are short or moderate say up to 4 m and loads are comparatively lighter.
Section on ab joist wedges floor boards 300 400 mm herring bone strutting 9.
1 ft 0 3048 m.
The widest span in the floor joist span table in part 2 of this tutorial module showed that floor joists can span 17 2 if they are 2 x 12s spaced 12 o c.
Around floor openings such as stairs it will be necessary to install larger or double triple timber trimmers bolted together to carry the floor joists see guide leaflet 6 for information.
Single joist timber floors.
Ce 200 details of construction.
If your home is more than 20 years old your floor joists are most likely solid wood 2x8s 2x10s or 2x12s.
2 grade of douglas fir are indicated below.
The floor consists of wooden joists also called bridging joists spaced 30 to 40 cm apart and supported on end walls.
In these cases the joist hangers will be 4.
Framed triple joist timber floor.
Maximum floor joist span for no.
So the house dimensions will now be 24 x 13.
Dead load weight of structure and fixed loads 10 lbs ft 2.
Basement ground floor of timber 1 auditorium dances and dramas.
The notching and boring rules of thumb for solid lumber are shown in fig.
Let s expand our house beyond that 17 2 span capability to 24 feet wide.
Double and triple joist hangers are wider to accommodate either a thicker piece of lumber or two or three joists placed side by side.
You can notch and bore joists without sacrificing critical strength but you must follow the rules.
Double and triple joist hangers.
