If your home is more than 20 years old your floor joists are most likely solid wood 2x8s 2x10s or 2x12s.
Triple joist timber floor section.
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.
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.
Let s expand our house beyond that 17 2 span capability to 24 feet wide.
Dead load weight of structure and fixed loads 10 lbs ft 2.
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.
1 psf lb f ft 2 47 88 n m 2.
Section on ab joist wedges floor boards 300 400 mm herring bone strutting 9.
2 grade of douglas fir are indicated below.
In these cases the joist hangers will be 4.
1 ft 0 3048 m.
Framed triple joist timber floor.
The notching and boring rules of thumb for solid lumber are shown in fig.
Live load is weight of furniture wind snow and more.
Framed or triple joists timber floors.
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.
You can notch and bore joists without sacrificing critical strength but you must follow the rules.
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.
True floor joist span calculations can only be made by a structural engineer or contractor.
Basement ground floor of timber 1 auditorium dances and dramas.
Single joist timber floors.
With all joined timbers supported by fully nailed proprietary joist hangers.
Follow the rules to keep your floor solid.
Ce 200 details of construction.
The floor consists of wooden joists also called bridging joists spaced 30 to 40 cm apart and supported on end walls.
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.
Double and triple joist hangers.
