Most deck footings are spaced approximately:

• 6–8 feet apart for smaller residential decks
• 8–10 feet apart for many standard deck designs
• 10+ feet apart only when larger beams and engineered designs are used

There is no universal footing spacing requirement because spacing is determined by the structural design of the deck.

Footing spacing is typically controlled by beam spans and post spacing rather than deck size alone.

Five primary factors determine footing spacing on residential decks.

Most homeowners assume footing spacing is determined by deck dimensions. In reality, beam design usually controls footing placement.

Footing spacing affects nearly every structural component above the foundation.

Changing footing locations can affect:

• Beam sizes
• Post spacing
• Footing diameter
• Concrete volume
• Material costs
• Labor requirements
• Inspection approval

Efficient footing layouts often reduce both framing costs and foundation costs.

Many homeowners use these terms interchangeably, but they are not always identical.

In most residential deck designs, each footing supports a post, which means footing spacing and post spacing are often very similar.

However, some structural configurations may include multiple posts, specialty brackets, or engineered systems that alter this relationship.

Related: Deck Post Spacing Chart

Spacing beyond 10 feet often requires significantly larger beams and may increase overall project costs even if fewer footings are installed.

A common misconception is that adding more footings automatically creates a stronger deck.

While additional footings can reduce beam spans, they also increase:

• Excavation
• Concrete volume
• Hardware requirements
• Labor costs
• Foundation costs

The most efficient design usually balances footing count with beam sizing and post spacing.

Footings are generally located where structural loads are transferred into the ground.

Common factors influencing footing placement include:

• Beam locations
• Post locations
• Stair attachment points
• Concentrated loads
• Hot tubs
• Outdoor kitchens
• Roof structures

Large concentrated loads frequently require additional footings beyond what would normally be required for a standard deck.

Footing spacing and beam sizing are directly connected.

As footing spacing increases:

• Beam spans increase
• Beam loads increase
• Beam sizes often increase

Many homeowners attempt to reduce footing count without realizing that larger beams may offset any savings.

Related: Deck Beam Span Chart

Using One Chart for Every Deck

There is no universal footing spacing chart that applies to every deck design.

Ignoring Beam Design

Beam sizing often controls footing spacing more than deck dimensions.

Assuming Fewer Footings Always Save Money

Larger beam requirements can offset footing savings.

Ignoring Soil Conditions

Weak soils may require larger footings or alternative layouts.

Deck size influences footing spacing, but not in the way many homeowners expect.

Larger decks do not automatically require wider footing spacing. In many cases, larger decks require additional beams and additional footings to maintain safe structural loads.

Actual spacing depends on beam design, post locations, and structural loading conditions.

Beam design is often the single biggest factor controlling footing spacing.

Larger beams can generally span farther between posts, allowing greater footing spacing.

Before finalizing footing locations, review the Deck Beam Span Chart.

Soil conditions affect how loads are transferred into the ground.

In some cases, weaker soils may require:

• Larger footing diameters
• Additional footings
• Shorter spans between supports
• Engineering review

Weak soils often require foundation adjustments even when deck dimensions remain unchanged.

Footing spacing directly affects both foundation costs and framing costs.

Wider spacing generally reduces:

• Excavation requirements
• Concrete volume
• Footing count

However, wider spacing may also require:

• Larger beams
• More expensive framing lumber
• Additional engineering review

The lowest-cost design is not always the design with the fewest footings.

Related: Deck Footing Cost

A typical 12×12 deck may use:

• 4 footings
• One beam
• Approximately 6–8 feet between footings

Actual spacing varies based on beam sizing and local code requirements.

A typical 12×16 deck often uses:

• 6 footings
• One or two beams
• Approximately 6–10 feet between footings

Larger spans may require upgraded beam sizes.

A typical 16×20 deck may require:

• 8–12 footings
• Multiple beam lines
• Additional structural support locations

Large decks often require more foundation planning than homeowners initially expect.

Low Risk

• Ground-level deck
• Stable soil
• Standard residential loads
• Simple rectangular layout

Moderate Risk

• Elevated deck
• Large spans
• Clay or sandy soils
• Complex layouts

High Risk

• Steep slopes
• Fill material
• Hot tubs
• Outdoor kitchens
• Roof structures

Higher-risk projects often benefit from professional design review before construction begins.

• Deck Footing Calculator
• Deck Footing Size Chart
• Deck Post Spacing Chart
• Deck Beam Span Chart
• Deck Footing Cost
• Deck Framing Cost
• Deck Construction Guide

Accurate footing spacing starts with accurate layout. These tools can help homeowners plan footing locations, verify spacing, and improve foundation accuracy before excavation begins.

Bosch Blaze GLM165-40 Laser Distance Measure

Useful for footing layouts, beam locations, and post spacing measurements.

View Bosch Blaze Laser Distance Measure →

DEWALT 25-Foot Tape Measure

Essential for verifying footing spacing and structural layouts.

View DEWALT Tape Measure →

String Line & Stakes Kit

Helpful for establishing straight footing lines and accurate beam locations.

View String Line & Stakes Kit →

Johnson Torpedo Level

Useful for checking footing and post alignment during construction.

View Johnson Torpedo Level →

Simpson Strong-Tie ABA Adjustable Post Base

Creates the connection between deck posts and footings while helping protect posts from moisture.

View Simpson Strong-Tie ABA Post Base →

How far apart should deck footings be?

Most residential deck footings are spaced between 6 and 10 feet apart, although actual spacing depends on beam design, loads, soil conditions, and local code requirements.

Can deck footings be spaced 12 feet apart?

Sometimes, but spacing beyond 10 feet often requires significantly larger beams and may require engineering review.

Does footing spacing affect beam size?

Yes. Wider footing spacing generally increases beam span requirements and often requires larger beams.

Is footing spacing the same as post spacing?

In many residential decks they are similar, but footing spacing and post spacing are not always identical.

Do larger decks require wider footing spacing?

Not necessarily. Larger decks often require additional footings rather than wider spacing.

Does soil type affect footing spacing?

Yes. Poor soil conditions may require larger footings, additional footings, or different structural layouts.

The Backyard Standard reviews technical guidance from recognized building-code and deck-construction organizations when developing structural planning resources.

• American Wood Council (AWC)
• AWC DCA 6 Residential Wood Deck Construction Guide
• International Code Council (ICC)
• North American Deck and Railing Association (NADRA)

Deck footing spacing is one of the most important foundation design decisions in any deck project. Proper spacing creates an efficient load path from the deck structure into the soil while balancing footing count, beam size, and overall project cost.