1. What is Deck Post Footing Size Calculation?

The deck post footing size calculation determines the required base area for deck footings based on the load they will carry and the soil's bearing capacity. Proper footing sizing prevents settling and ensures structural stability.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( Load \) — Total weight the footing will support (lbs)
• \( Soil\ Capacity \) — Soil bearing capacity (psf)
• \( Size \) — Required footing area (sq ft)

Explanation: The formula calculates the minimum area needed to distribute the load so the soil pressure doesn't exceed its capacity.

3. Importance of Proper Footing Sizing

Details: Correct footing size prevents differential settling, maintains deck level, and ensures safety under all load conditions.

4. Using the Calculator

Tips: Enter the total load in pounds and soil capacity in 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 capacity?
A: Consult local building codes or have a geotechnical engineer perform a soil test.

Q2: What loads should be included?
A: Include dead loads (deck weight) and live loads (people, furniture, snow).

Q3: Is this calculation for frost-protected footings?
A: No, frost depth requirements are separate and must be considered in footing depth.

Q4: How does footing shape affect this?
A: The formula gives area - shape can be round or square as long as area is achieved.

Q5: What safety factor should be used?
A: Most codes require a safety factor of 2-3 on soil capacity calculations.