Load Bearing Wall Beam Calculator

Calculator Inputs

Beam Span (m)

Wall Height Above Beam (m)

Wall Thickness (mm)

Masonry Unit Weight (kN/m³)

Floor Tributary Width (m)

Floor Dead Load (kN/m²)

Floor Live Load (kN/m²)

Roof Tributary Width (m)

Roof Dead Load (kN/m²)

Roof Live Load (kN/m²)

Beam Width (mm)

Beam Depth (mm)

Beam Density (kN/m³)

Concrete Strength f'c (MPa)

Steel Yield Strength fy (MPa)

Bearing Length Each Side (mm)

Allowable Bearing Stress (MPa)

Deflection Limit Ratio

Dead Load Factor

Live Load Factor

Support Condition

Wall Load Method

Elastic Modulus Override (MPa)

Tip: set floor or roof tributary values to zero when they do not apply. The modulus override is optional.

Example Data Table

This sample uses a simply supported beam, 45° wall load method, and the default values shown in the form.

Item	Example Value
Beam span	3.00 m
Wall height above beam	1.20 m
Wall thickness	200 mm
Masonry unit weight	20.00 kN/m³
Floor tributary width / loads	2.00 m, 4.00 dead, 2.50 live
Roof tributary width / loads	1.50 m, 2.00 dead, 0.75 live
Beam size	230 mm × 450 mm
Approximate service line load	24.409 kN/m
Approximate ultimate line load	31.741 kN/m
Approximate ultimate moment	35.708 kN·m
Approximate ultimate shear	47.611 kN
Approximate deflection	0.573 mm

Formula Used

1) Effective wall load height

Using a 45° arching assumption: h_eff = min(h_wall, span / 2)
Using full wall height: h_eff = h_wall

2) Wall dead load on beam

W_wall = h_eff × t_wall × γ_masonry × span

3) Floor and roof loads

W = span × tributary width × area load

4) Beam self-weight

W_beam = b × h × γ_beam × span

5) Line loads

w_dead = total dead / span
w_live = total live / span
w_u = 1.2D + 1.6L by default, but factors are user-adjustable.

6) Basic beam actions

Simply supported: V = wL / 2, M = wL² / 8
Fixed-fixed: M = wL² / 12
Cantilever: V = wL, M = wL² / 2

7) Deflection estimate

δ = C × wL⁴ / EI
Where C depends on support condition. Gross section inertia is approximated with I = bh³ / 12.

8) Preliminary sizing checks

Z_req = M_u / (0.9 f_y)
A_s,req ≈ M_u / (0.81 f_y d)
σ_bearing = R / A_bearing

How to Use This Calculator

Enter the beam span and the wall height directly loading the beam.
Enter wall thickness and masonry unit weight to estimate wall dead load.
Add floor and roof tributary widths only when those areas deliver load to the beam.
Enter beam dimensions, material strengths, and bearing length for preliminary checks.
Choose the support condition matching the actual structural behavior.
Select the wall load method. Use 45° arching when a limited loaded wedge is appropriate.
Click the calculate button. Review loads, reactions, moment, shear, deflection, and checks.
Download CSV or PDF for reporting, then confirm the design with a licensed structural engineer.

FAQs

1) What loads does this calculator include?

It includes wall dead load, floor dead load, floor live load, roof dead load, roof live load, and beam self-weight. You can set any nonapplicable component to zero.

2) Why is there a 45° arching option?

That option limits the effective wall height acting on the beam. It is commonly used for preliminary lintel or beam checks where only a load wedge above the opening contributes.

3) When should I enter floor tributary width?

Use a nonzero tributary width when joists, slabs, or framing deliver floor load to the wall beam. Leave it at zero when the beam only supports masonry above.

4) What support condition should I choose?

Choose simply supported for typical bearing ends, fixed-fixed only when both ends truly restrain rotation, and cantilever when one end is fixed and the other projects free.

5) Is the deflection result exact?

No. It is a gross-section elastic estimate. Cracking, reinforcement ratio, creep, composite action, and connection flexibility can change real deflection significantly.

6) Why does bearing length matter?

Bearing length affects contact area at the support. A longer bearing reduces support stress and often improves constructability, especially on masonry or concrete walls.

7) Can I use this for steel, concrete, or masonry beams?

It is best suited for preliminary wall beam sizing and comparison. The section modulus and steel area outputs are simplified checks, not complete material-specific code design.

8) Can this replace a structural engineer’s design?

No. Final design must consider local code requirements, load combinations, crack control, shear reinforcement, seismic effects, fire rating, detailing, and support conditions.