Masonry Wall Design Calculator

Design reinforced masonry walls: check slenderness, compressive capacity, moment capacity, and load adequacy.

Wall Height

Wall Thickness

TMS 402: min 150 mm load-bearing; 200 mm (8") standard CMU; 300 mm (12") for high axial loads

Wall Length

Block Compressive Strength

MPa

ASTM C90 / TMS 402: standard CMU f'm 13–15 MPa; high-strength 20–30 MPa; min 13.8 MPa

Mortar Type

(1=M, 2=S, 3=N)

ASTM C270: Type M ≥17.2 MPa (foundations); Type S ≥12.4 MPa (reinforced); Type N ≥5.2 MPa (exterior above grade)

Rebar Spacing

Rebar Size (diameter)

Applied Axial Load

Tab to move between fields

Compressive Capacity

555,153 N

Allowable Axial Load

555,153 N

Adequate?

1 (1=yes, 0=no)

Slenderness Ratio (h/t)15

Moment Capacity12,725,984 N·mm

How to Use This Calculator

Enter the wall height, thickness, and the design wind pressure in psf.
Input the masonry compressive strength (f'm) and the reinforcing steel yield strength.
Set the axial load from floors or roof above in plf.
Review the Moment Capacity, Shear Capacity, and the Combined Stress Check.
Ensure unity ratios for bending and shear are both under 1.0 per TMS 402.

How the result changes with Wall Thickness

Wall Thickness	Compressive Capacity	Allowable Axial Load	Adequate?
130	355,122 N	355,122 N	1 (1=yes, 0=no)
205	569,350 N	569,350 N	1 (1=yes, 0=no)
295	823,989 N	823,989 N	1 (1=yes, 0=no)
370	1,035,475 N	1,035,475 N	1 (1=yes, 0=no)

Wall Height: Unsupported height of the masonry wall between lateral supports.
Wall Thickness: Nominal thickness of the masonry wall per TMS 402 (Masonry Building Code). Standard CMU: 100 mm (4"), 150 mm (6"), 200 mm (8", most common), 250 mm (10"), 300 mm (12"). TMS 402 requires minimum 150 mm for load-bearing.
Wall Length: Length of wall section under consideration.
Block Compressive Strength: Compressive strength of the concrete masonry unit per ASTM C90. Standard CMU minimum f'm = 13.8 MPa (2,000 psi); high-strength CMU 20–40 MPa. Per TMS 402, f'm is the specified compressive strength of the assembly, typically 13–20 MPa.
Mortar Type: Mortar type per ASTM C270. Type M (1): highest strength ≥17.2 MPa, below grade/foundations; Type S (2): ≥12.4 MPa, reinforced masonry/below grade; Type N (3): ≥5.2 MPa, above grade/exterior walls. TMS 402 specifies mortar by type.
Rebar Spacing: Center-to-center spacing of vertical reinforcing bars.
Rebar Size (diameter): Nominal diameter of vertical reinforcing bars. Common: 10, 13, 16, 19 mm.
Applied Axial Load: Factored axial compression load applied to the wall section.

Identify Input Parameters
4 parameters
Wall Height = 3, Wall Thickness = 200, Wall Length = 1000, Block Compressive Strength = 15 = 8 input(s) provided
Calculate Compressive Capacity
Compressive Capacity
555153 = 555153
Calculate Allowable Axial Load
Allowable Axial Load
555153 = 555153
Calculate Adequate?
Adequate?
1 = 1
Calculate Slenderness Ratio
Slenderness Ratio
15 = 15
Calculate Moment Capacity
Moment Capacity
12725984 = 12725984