ASCE 7-22 Tornado Load Calculator

Professional ASCE 7-22 Chapter 32 Tornado Load Calculator for MWFRS and C&C. Compute tornado design pressures using mapped V_T and tornado-specific coefficients with inline validation and accessible UX.

ASCE 7-22 Tornado Load Calculator

This professional calculator helps structural engineers compute tornado design pressures for MWFRS and C&C per ASCE/SEI 7-22 Chapter 32. It exposes the tornado-specific coefficients, provides inline validation, and links to authoritative sources.

Data Source & Methodology

Authoritative Data Source: ASCE/SEI 7-22, Chapter 32 — Tornado Loads. Supporting references:

All calculations strictly follow the equations and factors provided by this source.

The Formulas Explained

\[ q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2 \]
\[ p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT}) \]
\[ \text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})] \] \[ \text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT}) \]

Glossary of Variables

SymbolNameNotes
VTMapped tornado 3-s gust at 10 m (mph)From ASCE Hazard Tool; depends on Risk Category & Ae.
qTTornado velocity pressure (psf)Computed from VT and coefficients.
KzT, Kzt, KeExposure/Topography/ElevationTornado-specific factors per Chapter 32.
KdT, KvT, GTDirectionality/Adjustment/GustModifiers for tornado loading.
Cp, (GCpiT)External/Internal coefficientsIncludes APC in internal coefficients.

How It Works: A Step-by-Step Example

Scenario: RC IV, Exposure B, VT=120 mph, KzT=0.85, Kzt=1.00, Ke=1.00, KdT=1.00, KvT=1.00, GT=0.85, Cp=−0.9, (GCpiT)=+0.18.

  1. Compute \(q_T = 0.00256 \cdot 0.85 \cdot 1.00 \cdot 1.00 \cdot 120^2 \approx 31.5\) psf.
  2. Take \(q_{iT} = q_T = 31.5\) psf (if not otherwise specified).
  3. MWFRS: \(p_T \approx 31.5\cdot0.85\cdot1\cdot1\cdot(-0.9) - 31.5\cdot(0.18) \approx -29.8\) psf uplift.

Frequently Asked Questions

Does ASCE 7-22 require tornado design for all buildings?

No. The requirement applies to Risk Category III & IV in tornado-prone regions.

Where do I get VT?

Use the ASCE Hazard Tool with location, Risk Category, and Ae bucket.

Are tornado loads separate from wind loads?

Yes. They are checked per Chapter 32 and compared within Chapter 2 load combinations.

How is APC handled?

(GCpiT) values include Atmospheric Pressure Change effects for tornado events.

When do tornado loads control?

Often for RC IV essential facilities with large Ae in central/southeast U.S.

Debris/glazing?

See Chapter 32 provisions and local code adoption for debris and glazing protection.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted LaTeX)
\[q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2\]
q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2
Formula (extracted LaTeX)
\[p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT})\]
p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT})
Formula (extracted LaTeX)
\[\text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})]\]
\text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})]
Formula (extracted LaTeX)
\[\text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT})\]
\text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT})
Formula (extracted text)
\[ q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2 \] \[ p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT}) \] \[ \text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})] \] \[ \text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT}) \]
Variables and units
  • No variables provided in audit spec.
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn

Full original guide (expanded)

ASCE 7-22 Tornado Load Calculator

This professional calculator helps structural engineers compute tornado design pressures for MWFRS and C&C per ASCE/SEI 7-22 Chapter 32. It exposes the tornado-specific coefficients, provides inline validation, and links to authoritative sources.

Data Source & Methodology

Authoritative Data Source: ASCE/SEI 7-22, Chapter 32 — Tornado Loads. Supporting references:

All calculations strictly follow the equations and factors provided by this source.

The Formulas Explained

\[ q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2 \]
\[ p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT}) \]
\[ \text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})] \] \[ \text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT}) \]

Glossary of Variables

SymbolNameNotes
VTMapped tornado 3-s gust at 10 m (mph)From ASCE Hazard Tool; depends on Risk Category & Ae.
qTTornado velocity pressure (psf)Computed from VT and coefficients.
KzT, Kzt, KeExposure/Topography/ElevationTornado-specific factors per Chapter 32.
KdT, KvT, GTDirectionality/Adjustment/GustModifiers for tornado loading.
Cp, (GCpiT)External/Internal coefficientsIncludes APC in internal coefficients.

How It Works: A Step-by-Step Example

Scenario: RC IV, Exposure B, VT=120 mph, KzT=0.85, Kzt=1.00, Ke=1.00, KdT=1.00, KvT=1.00, GT=0.85, Cp=−0.9, (GCpiT)=+0.18.

  1. Compute \(q_T = 0.00256 \cdot 0.85 \cdot 1.00 \cdot 1.00 \cdot 120^2 \approx 31.5\) psf.
  2. Take \(q_{iT} = q_T = 31.5\) psf (if not otherwise specified).
  3. MWFRS: \(p_T \approx 31.5\cdot0.85\cdot1\cdot1\cdot(-0.9) - 31.5\cdot(0.18) \approx -29.8\) psf uplift.

Frequently Asked Questions

Does ASCE 7-22 require tornado design for all buildings?

No. The requirement applies to Risk Category III & IV in tornado-prone regions.

Where do I get VT?

Use the ASCE Hazard Tool with location, Risk Category, and Ae bucket.

Are tornado loads separate from wind loads?

Yes. They are checked per Chapter 32 and compared within Chapter 2 load combinations.

How is APC handled?

(GCpiT) values include Atmospheric Pressure Change effects for tornado events.

When do tornado loads control?

Often for RC IV essential facilities with large Ae in central/southeast U.S.

Debris/glazing?

See Chapter 32 provisions and local code adoption for debris and glazing protection.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted LaTeX)
\[q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2\]
q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2
Formula (extracted LaTeX)
\[p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT})\]
p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT})
Formula (extracted LaTeX)
\[\text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})]\]
\text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})]
Formula (extracted LaTeX)
\[\text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT})\]
\text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT})
Formula (extracted text)
\[ q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2 \] \[ p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT}) \] \[ \text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})] \] \[ \text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT}) \]
Variables and units
  • No variables provided in audit spec.
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn

ASCE 7-22 Tornado Load Calculator

This professional calculator helps structural engineers compute tornado design pressures for MWFRS and C&C per ASCE/SEI 7-22 Chapter 32. It exposes the tornado-specific coefficients, provides inline validation, and links to authoritative sources.

Data Source & Methodology

Authoritative Data Source: ASCE/SEI 7-22, Chapter 32 — Tornado Loads. Supporting references:

All calculations strictly follow the equations and factors provided by this source.

The Formulas Explained

\[ q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2 \]
\[ p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT}) \]
\[ \text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})] \] \[ \text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT}) \]

Glossary of Variables

SymbolNameNotes
VTMapped tornado 3-s gust at 10 m (mph)From ASCE Hazard Tool; depends on Risk Category & Ae.
qTTornado velocity pressure (psf)Computed from VT and coefficients.
KzT, Kzt, KeExposure/Topography/ElevationTornado-specific factors per Chapter 32.
KdT, KvT, GTDirectionality/Adjustment/GustModifiers for tornado loading.
Cp, (GCpiT)External/Internal coefficientsIncludes APC in internal coefficients.

How It Works: A Step-by-Step Example

Scenario: RC IV, Exposure B, VT=120 mph, KzT=0.85, Kzt=1.00, Ke=1.00, KdT=1.00, KvT=1.00, GT=0.85, Cp=−0.9, (GCpiT)=+0.18.

  1. Compute \(q_T = 0.00256 \cdot 0.85 \cdot 1.00 \cdot 1.00 \cdot 120^2 \approx 31.5\) psf.
  2. Take \(q_{iT} = q_T = 31.5\) psf (if not otherwise specified).
  3. MWFRS: \(p_T \approx 31.5\cdot0.85\cdot1\cdot1\cdot(-0.9) - 31.5\cdot(0.18) \approx -29.8\) psf uplift.

Frequently Asked Questions

Does ASCE 7-22 require tornado design for all buildings?

No. The requirement applies to Risk Category III & IV in tornado-prone regions.

Where do I get VT?

Use the ASCE Hazard Tool with location, Risk Category, and Ae bucket.

Are tornado loads separate from wind loads?

Yes. They are checked per Chapter 32 and compared within Chapter 2 load combinations.

How is APC handled?

(GCpiT) values include Atmospheric Pressure Change effects for tornado events.

When do tornado loads control?

Often for RC IV essential facilities with large Ae in central/southeast U.S.

Debris/glazing?

See Chapter 32 provisions and local code adoption for debris and glazing protection.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted LaTeX)
\[q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2\]
q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2
Formula (extracted LaTeX)
\[p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT})\]
p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT})
Formula (extracted LaTeX)
\[\text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})]\]
\text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})]
Formula (extracted LaTeX)
\[\text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT})\]
\text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT})
Formula (extracted text)
\[ q_T = 0.00256 \; K_{zT} K_{zt} K_e V_T^2 \] \[ p_T = q_T \; G_T \; K_{dT} \; K_{vT} \; C_p - q_{iT}\,(GC_{piT}) \] \[ \text{C\&C (h \le 60 ft): } p_T = q_{hT}[K_{dT}K_{vT}(GC_p)-(GC_{piT})] \] \[ \text{C\&C (h > 60 ft): } p_T = q_T K_{dT}K_{vT}(GC_p) - q_{iT}(GC_{piT}) \]
Variables and units
  • No variables provided in audit spec.
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
Formulas

(Formulas preserved from original page content, if present.)

Version 0.1.0-draft
Citations

Add authoritative sources relevant to this calculator (standards bodies, manuals, official docs).

Changelog
  • 0.1.0-draft — 2026-01-19: Initial draft (review required).