Microlam Beam Size Calculator

Microlam Beam Size Calculator

Results

Recommended Beam Size
Required Moment of Inertia ($I_{req}$) in$^4$
Required Section Modulus ($S_{req}$) in$^3$
This calculator provides an estimate for common building applications and is not a substitute for professional engineering advice. It assumes a simple beam with uniform load.

What Is a Microlam Beam?

A Microlam beam is a type of LVL (laminated veneer lumber). It is engineered by bonding thin wood veneers with adhesives under heat and pressure. The result is a high-strength, uniform, and reliable beam that outperforms traditional solid-sawn lumber.

Key advantages of Microlam beams include:

  • High strength-to-size ratio
  • Available in long lengths without warping
  • Consistent performance compared to solid lumber
  • Ideal for carrying heavy loads across wide spans

Because of these properties, Microlam beams are often used for:

  • Floor beams
  • Roof beams
  • Headers over doors and windows
  • Support in remodels and new builds

What Is a Microlam Beam Size Calculator?

The Microlam Beam Size Calculator is an online tool that helps you determine the minimum recommended size of a Microlam LVL beam for your project.

It uses three main inputs:

  1. Span (feet): The clear distance the beam must cover.
  2. Total Load (lbs): The weight the beam needs to support, including dead load (materials) and live load (people, furniture, snow, etc.).
  3. Microlam Grade: Different grades such as 1.8E, 2.0E, or 2.2E indicate stiffness and strength.

With this information, the calculator estimates:

  • Required Moment of Inertia (I) → relates to deflection control.
  • Required Section Modulus (S) → relates to bending strength.
  • Recommended Beam Size → chosen from common Microlam sizes that meet or exceed requirements.

How the Calculator Works (Plain-English Version)

The calculator uses standard beam formulas to check whether a beam can handle the given span and load.

  1. Span is converted to inches.
  2. Required I (moment of inertia) is calculated to control deflection.
  3. Required S (section modulus) is calculated to control bending stress.
  4. The tool compares your results with a list of common Microlam sizes.
  5. It suggests the smallest size that meets both strength and stiffness needs.

For example:

  • Span = 10 ft
  • Load = 5,000 lbs
  • Grade = 2.0E LVL

The calculator might recommend a 1.75″ × 9.5″ Microlam if it satisfies both deflection and bending limits.

Why Use This Calculator?

  • Saves time: No need to dive into complex beam tables.
  • Increases accuracy: Uses engineering formulas tailored to Microlam grades.
  • Improves planning: Helps with budgeting and material orders.
  • Supports DIYers and pros alike: Useful for homeowners, contractors, and architects.

Important Notes

While the Microlam Beam Size Calculator is a great starting point, it is not a substitute for professional engineering judgment. Real-world factors like:

  • Multiple spans
  • Point loads vs. uniform loads
  • Bearing conditions
  • Building codes
  • Local safety requirements

…can affect the final beam size you should use.

Always confirm with a structural engineer or building inspector before finalizing your design.