What is the typical span between floor joists in residential construction?

In residential construction, the typical span between floor joists is commonly set at 16 inches on center. This measurement strikes a balance between structural integrity and efficient use of materials. Spacing floor joists at this interval provides adequate support for the flooring system while allowing room for insulation between the joists, which contributes to energy efficiency.

When joists are spaced too far apart, such as 24 inches or more, it may lead to excessive deflection or sagging under load, compromising the stability and longevity of the floor. Conversely, spacing them too closely, like at 12 inches or less, can result in unnecessary material costs and construction time without significant added benefit in most residential applications.

In summary, the standard 16-inch spacing is widely adopted in the industry because it effectively balances performance, cost, and ease of installation in residential building projects.