Wooden Pergola Beam Size Calculator Australia

Minimum Depth Formula:

\[ d_{min} = \sqrt{ \frac{w L^2 \times 1000}{8 f_b} } \]

Minimum Depth (d_min):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Minimum Depth Formula?

The minimum depth formula calculates the required beam depth for Australian pergola construction based on distributed load, span length, and allowable bending stress. This ensures structural integrity and compliance with Australian building standards.

2. How Does the Calculator Work?

The calculator uses the minimum depth formula:

\[ d_{min} = \sqrt{ \frac{w L^2 \times 1000}{8 f_b} } \]

Where:

\( d_{min} \) — Minimum beam depth (mm)
\( w \) — Distributed load (kN/m)
\( L \) — Span length (m)
\( f_b \) — Allowable bending stress (MPa)

Explanation: The formula calculates the minimum depth required for a wooden beam to safely support the specified load over the given span while staying within the material's bending stress limits.

3. Importance of Beam Sizing

Details: Proper beam sizing is crucial for structural safety, preventing sagging or failure, and ensuring compliance with Australian building codes and standards for outdoor structures like pergolas.

4. Using the Calculator

Tips: Enter distributed load in kN/m, span length in meters, and allowable bending stress in MPa. All values must be positive numbers greater than zero for accurate calculations.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical bending stress value for Australian hardwood?
A: Typical values range from 15-25 MPa for most Australian hardwoods used in pergola construction.

Q2: How do I determine the distributed load for my pergola?
A: The distributed load includes dead load (weight of structure) and live load (snow, wind, people). Consult Australian Standard AS 1684 for specific requirements.

Q3: Does this calculation account for deflection limits?
A: This formula calculates for strength only. Deflection should be checked separately according to Australian standards.

Q4: Can I use this for other types of beams?
A: While the formula is generally applicable, always consult relevant Australian standards and a structural engineer for specific applications.

Q5: What safety factors are included?
A: The formula uses the allowable bending stress which typically includes appropriate safety factors as per Australian standards.