1. What is Deck Footing Calculation?

Deck footing calculation determines the required size of concrete footings to properly support a deck's weight and distribute the load to the soil. Proper footing prevents settling and structural failure.

2. How Does the Calculator Work?

The calculator uses the basic footing size formula:

Where:

• \( Load \) — Total weight the footing must support (lbs)
• \( Soil Bearing Capacity \) — Soil's ability to bear weight (psf)

Explanation: The calculation ensures the footing distributes the deck's weight over sufficient area so the soil can support it without excessive settling.

3. Importance of Proper Footing

Details: Correct footing size is crucial for deck safety and longevity. Undersized footings can lead to settling, tilting, or collapse, while oversized footings waste materials and increase costs unnecessarily.

4. Using the Calculator

Tips: Enter the total load in pounds and soil bearing capacity in pounds per square foot (psf). Typical soil capacities range from 1,500 psf (soft clay) to 4,000 psf (dense gravel).

5. Frequently Asked Questions (FAQ)

Q1: How do I determine my soil's bearing capacity?
A: A geotechnical engineer can test your soil, or you can use conservative estimates (e.g., 1,500 psf for clay, 2,000 psf for sandy loam, 3,000 psf for gravel).

Q2: What's included in the total load calculation?
A: Include dead load (deck materials), live load (people/furniture), and environmental loads (snow in northern climates).

Q3: How deep should footings be?
A: Footings must extend below the frost line in your area to prevent frost heave.

Q4: Can I use this for other structures?
A: The same principle applies to any structure, but consult an engineer for large or complex projects.

Q5: What's the minimum footing size?
A: Most codes require at least 12" diameter footings regardless of calculation results.