Enter the effective depth (mm), the diameter of the bar (mm), and the clear cover size (mm) into the Beam Length Calculator. The calculator will evaluate the Beam Length.

- All Length Calculators
- Length to Beam Ratio Calculator
- Wood Beam Cost Calculator
- Rafter Length Calculator

## Beam Length Formula

The following formula is used to calculate the Beam Length.

BEL = ED + D/2 + CS

- Where BEL is the Beam Length (in)
- ED is the effective depth (mm)
- D is the diameter of the bar (mm)
- CS is the clear cover size (mm)

To calculate the beam length, add the effective depth to half the diameter, then add the clear cover size.

## How to Calculate Beam Length?

The following two example problems outline the steps and information needed to calculate the Beam Length.

**Example Problem #1**

- First, determine the effective depth (mm).
- The effective depth (mm) is calculated to be : 3.

- Next, determine the diameter of the bar (mm).
- The diameter of the bar (mm) is measured to be: 4.

- Next, determine the clear cover size (mm).
- The clear cover size (mm) is found to be: 6.

- Finally, calculate the Beam Length using the formula above:

BEL = ED + D/2 + CS

The values provided above are inserted into the equation below and computed.

BEL = 3 + 4/2 + 6 = 11 (in)

**Example Problem #2**

The variables required for this problem are provided below:

effective depth (mm) = 6

diameter of the bar (mm) = 8

clear cover size (mm) = 9

Test your knowledge using the equation and check your answer with the calculator.

BEL = ED + D/2 + CS =** **(in)