Deflection Calculator
Calculate beam and slab deflections under various loading conditions. Check against allowable deflection limits per building codes (L/250, L/360, etc.).
Formula: δ = 5wL⁴/384EI
General floors, roofs
Enter member dimensions and loading to calculate deflection
Notes:
- Calculations use gross (uncracked) section properties
- Long-term deflection may be 2-3× elastic deflection
- Cracked section analysis may give higher deflections
- Consider camber for beams with significant deflection
- Verify with detailed structural analysis for critical members
IMPORTANT DISCLAIMER
This calculator provides PRELIMINARY ESTIMATES ONLY and is intended for planning and budgeting purposes. Results should NOT be used for final structural design or construction without verification by a licensed Professional Engineer (PE) or Chartered Engineer (CEng).
By using this tool, you acknowledge that:
1. All calculations are indicative and may not account for site-specific conditions, load combinations, or local code requirements.
About This Calculator
This deflection calculator verifies that beams, slabs, and cantilevers meet serviceability requirements under applied loads. In UAE high-rise construction, excessive deflection can cause cracking in partitions, damage to finishes, and occupant discomfort. The calculator checks instantaneous and long-term deflections against code limits (L/250 for total, L/360 for live load).
When to Use This Calculator
- Verifying beam and slab serviceability before construction
- Checking long-span members in commercial buildings
- Evaluating cantilever balconies and projections
- Assessing floor vibration concerns in office spaces
- Reviewing structural adequacy for partition support
How to Use This Calculator
Enter span length
Input the clear span between supports in meters
Select member type
Choose beam, slab, or cantilever configuration
Input section properties
Enter moment of inertia and elastic modulus
Apply loads
Enter dead load, live load, and any sustained loads
Review deflection check
Compare calculated vs allowable deflection ratios
Typical Scenarios in UAE & Gulf Projects
Checking 12m span composite beams in a retail expansion. L/360 limit for live load deflection to prevent cracking in terrazzo flooring. Long-term deflection includes creep factor for 50-year design life.
Verifying 3.5m cantilever balcony deflections. Critical check for L/180 tip deflection limit to prevent visible sag and waterproofing membrane stress. Includes dynamic loading for occupant comfort.
Frequently Asked Questions
Take Your Calculations Further
This calculator reflects the logic built into Arkan's construction management platform.
Last Updated: January 2026
Standards Reference: ACI 318-19, BS 8110, Eurocode 2, IBC Serviceability Limits