Joist

Flooring layer

Definition of Joist

A timber, concrete, or steel horizontal structure used to support the structure of a floor or a ceiling. Joists are arranged parallel to one another to provide a uniform and stable surface for flooring materials.

The size and spacing of joists determine the structural integrity of a floor. The spacing is determined by joist timber size, flooring requirements, and building codes.

Joists are typically placed between 12″ and 24″ apart.

The table below provides an overview of standard joist spacing measurements according to timber size.

Joist Timber Size 12″ 16″ 24″
2 x 6 10 – 10 9 – 10 8 – 7
2 x 8 13 – 1 12 – 4 11 – 3
2 x 10 15 – 3 14 – 4 13 – 6
2 x 12 17 – 2 16 – 2 15 – 3

table source: https://dreamcivil.com/floor-joist/

Example of Joist in a Sentence

“A joist can support the weight of various flooring materials plus the furniture, appliances, and other objects placed on the floor.”

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