Deck post spacing depends on the type of posts, materials used, deck design, and local building codes. Here is a detailed overview:
Typical Deck Post Spacing Guidelines
- Deck railing posts:
- Most wood railing posts (4x4) should be spaced no more than 6 feet apart, on-center, to ensure stability and meet building codes.
- Larger wood posts (6x6) can span up to 8 feet apart.
- Some metal or composite railing systems allow wider spacing, up to 8 to 10 feet, but always verify with manufacturer instructions and local codes
- Structural deck posts (supporting beams and joists):
- Generally, deck support posts should be spaced no more than 8 feet apart. This spacing depends on the size and span of the beams and joists they support. For example, if joists span less than 6 feet, 8-foot post spacing may be acceptable.
- For heavier loads or larger spans, posts may need to be spaced closer together, sometimes as close as every 4 feet for a very rigid frame
Factors Influencing Post Spacing
- Material strength: Wood posts usually require closer spacing than metal posts due to strength differences.
- Load and deck height: Higher decks or decks with heavy loads (like hot tubs) require closer post spacing for safety.
- Local building codes: Always check local regulations, as they may impose stricter requirements than general guidelines.
- Aesthetics: Even spacing (e.g., dividing a 15-foot railing into three equal 5-foot spans) looks better and maintains structural integrity
Summary
Post Type| Typical Maximum Spacing| Notes
---|---|---
Wood railing posts (4x4)| 6 feet (on-center)| Common code requirement
Wood railing posts (6x6)| Up to 8 feet| For stronger posts
Metal/composite railing| 8 to 10 feet| Check manufacturer guidelines
Structural deck posts| Up to 8 feet| Depends on beam/joist spans and load
Heavy loads (e.g., hot tubs)| Closer than 8 feet| Requires engineering and
permits
In conclusion, deck railing posts are typically spaced no more than 6 feet apart, while structural support posts can be spaced up to 8 feet apart depending on beam and joist spans and load requirements. Always verify with local building codes and material specifications to ensure safety and compliance
