This professional-grade tool computes the flat roof snow load (pf) per ASCE 7 methodology and optionally the balanced sloped roof load using a user-provided Cs. Designed for structural engineers and plan reviewers, it prioritizes correctness, accessibility, and auditability.

Authoritative Data Source & Methodology

Primary reference: ASCE/SEI 7-22, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, Chapter 7 (Snow Loads). Use the ASCE Hazard Tool for site-specific pg. All calculations are strictly based on the formulas and data provided by this source.

The Formulas Explained

Flat roof snow load:

\\[ p_f = 0.7\, C_e\, C_t\, I\, p_g \\]

Optional balanced sloped roof load:

\\[ p_s = C_s\, p_f \\]

Glossary of Variables

  • pg: Ground snow load (site-specific).
  • Ce: Exposure factor (terrain/obstructions).
  • Ct: Thermal factor (roof heat loss/conditions).
  • I: Importance factor (per Risk Category).
  • pf: Flat roof snow load (computed).
  • Cs: Sloped roof factor (depends on slope/surface/thermal conditions).
  • ps: Balanced sloped roof load (if Cs provided).

How It Works: A Step-by-Step Example

Assume Imperial. Let pg = 30 psf, Ce = 1.0, Ct = 1.0, I = 1.0.

\\( p_f = 0.7 \times 1.0 \times 1.0 \times 1.0 \times 30 = 21 \text{ psf} \\)

If Cs = 0.9, then \\( p_s = 0.9 \times 21 = 18.9 \text{ psf} \\).

Note: Drift, sliding, unbalanced loading, rain-on-snow, and ponding require additional checks per ASCE 7-22 Chapter 7.

Frequently Asked Questions (FAQ)

Where do I get pg?

From the ASCE Hazard Tool or your AHJ’s published values.

Does this include drift/sliding?

No; this tool covers balanced flat/sloped roof loads only.

Which units should I use?

Select psf (Imperial) or kPa (SI). The tool converts consistently.

How do I choose Ce, Ct, I?

Per ASCE 7-22 and local amendments; consult a licensed engineer.

Why is Cs optional?

Cs applies to sloped roofs and depends on slope/surface/thermal regime.

Permit submittal?

Use as an engineering aid; sealed calcs may be required.

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)
\[p_f = 0.7\, C_e\, C_t\, I\, p_g \\]
p_f = 0.7\, C_e\, C_t\, I\, p_g \
Formula (extracted LaTeX)
\[p_s = C_s\, p_f \\]
p_s = C_s\, p_f \
Formula (extracted text)
Flat roof snow load: \\[ p_f = 0.7\, C_e\, C_t\, I\, p_g \\] Optional balanced sloped roof load: \\[ p_s = C_s\, p_f \\]
Formula (extracted text)
\\( p_f = 0.7 \times 1.0 \times 1.0 \times 1.0 \times 30 = 21 \text{ psf} \\) If Cs = 0.9, then \\( p_s = 0.9 \times 21 = 18.9 \text{ psf} \\).
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
, ', svg: { fontCache: 'global' } };

This professional-grade tool computes the flat roof snow load (pf) per ASCE 7 methodology and optionally the balanced sloped roof load using a user-provided Cs. Designed for structural engineers and plan reviewers, it prioritizes correctness, accessibility, and auditability.

Authoritative Data Source & Methodology

Primary reference: ASCE/SEI 7-22, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, Chapter 7 (Snow Loads). Use the ASCE Hazard Tool for site-specific pg. All calculations are strictly based on the formulas and data provided by this source.

The Formulas Explained

Flat roof snow load:

\\[ p_f = 0.7\, C_e\, C_t\, I\, p_g \\]

Optional balanced sloped roof load:

\\[ p_s = C_s\, p_f \\]

Glossary of Variables

  • pg: Ground snow load (site-specific).
  • Ce: Exposure factor (terrain/obstructions).
  • Ct: Thermal factor (roof heat loss/conditions).
  • I: Importance factor (per Risk Category).
  • pf: Flat roof snow load (computed).
  • Cs: Sloped roof factor (depends on slope/surface/thermal conditions).
  • ps: Balanced sloped roof load (if Cs provided).

How It Works: A Step-by-Step Example

Assume Imperial. Let pg = 30 psf, Ce = 1.0, Ct = 1.0, I = 1.0.

\\( p_f = 0.7 \times 1.0 \times 1.0 \times 1.0 \times 30 = 21 \text{ psf} \\)

If Cs = 0.9, then \\( p_s = 0.9 \times 21 = 18.9 \text{ psf} \\).

Note: Drift, sliding, unbalanced loading, rain-on-snow, and ponding require additional checks per ASCE 7-22 Chapter 7.

Frequently Asked Questions (FAQ)

Where do I get pg?

From the ASCE Hazard Tool or your AHJ’s published values.

Does this include drift/sliding?

No; this tool covers balanced flat/sloped roof loads only.

Which units should I use?

Select psf (Imperial) or kPa (SI). The tool converts consistently.

How do I choose Ce, Ct, I?

Per ASCE 7-22 and local amendments; consult a licensed engineer.

Why is Cs optional?

Cs applies to sloped roofs and depends on slope/surface/thermal regime.

Permit submittal?

Use as an engineering aid; sealed calcs may be required.

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)
\[p_f = 0.7\, C_e\, C_t\, I\, p_g \\]
p_f = 0.7\, C_e\, C_t\, I\, p_g \
Formula (extracted LaTeX)
\[p_s = C_s\, p_f \\]
p_s = C_s\, p_f \
Formula (extracted text)
Flat roof snow load: \\[ p_f = 0.7\, C_e\, C_t\, I\, p_g \\] Optional balanced sloped roof load: \\[ p_s = C_s\, p_f \\]
Formula (extracted text)
\\( p_f = 0.7 \times 1.0 \times 1.0 \times 1.0 \times 30 = 21 \text{ psf} \\) If Cs = 0.9, then \\( p_s = 0.9 \times 21 = 18.9 \text{ psf} \\).
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
]], displayMath: [['\\[','\\]']] }, svg: { fontCache: 'global' } };, svg: { fontCache: 'global' } };

This professional-grade tool computes the flat roof snow load (pf) per ASCE 7 methodology and optionally the balanced sloped roof load using a user-provided Cs. Designed for structural engineers and plan reviewers, it prioritizes correctness, accessibility, and auditability.

Authoritative Data Source & Methodology

Primary reference: ASCE/SEI 7-22, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, Chapter 7 (Snow Loads). Use the ASCE Hazard Tool for site-specific pg. All calculations are strictly based on the formulas and data provided by this source.

The Formulas Explained

Flat roof snow load:

\\[ p_f = 0.7\, C_e\, C_t\, I\, p_g \\]

Optional balanced sloped roof load:

\\[ p_s = C_s\, p_f \\]

Glossary of Variables

  • pg: Ground snow load (site-specific).
  • Ce: Exposure factor (terrain/obstructions).
  • Ct: Thermal factor (roof heat loss/conditions).
  • I: Importance factor (per Risk Category).
  • pf: Flat roof snow load (computed).
  • Cs: Sloped roof factor (depends on slope/surface/thermal conditions).
  • ps: Balanced sloped roof load (if Cs provided).

How It Works: A Step-by-Step Example

Assume Imperial. Let pg = 30 psf, Ce = 1.0, Ct = 1.0, I = 1.0.

\\( p_f = 0.7 \times 1.0 \times 1.0 \times 1.0 \times 30 = 21 \text{ psf} \\)

If Cs = 0.9, then \\( p_s = 0.9 \times 21 = 18.9 \text{ psf} \\).

Note: Drift, sliding, unbalanced loading, rain-on-snow, and ponding require additional checks per ASCE 7-22 Chapter 7.

Frequently Asked Questions (FAQ)

Where do I get pg?

From the ASCE Hazard Tool or your AHJ’s published values.

Does this include drift/sliding?

No; this tool covers balanced flat/sloped roof loads only.

Which units should I use?

Select psf (Imperial) or kPa (SI). The tool converts consistently.

How do I choose Ce, Ct, I?

Per ASCE 7-22 and local amendments; consult a licensed engineer.

Why is Cs optional?

Cs applies to sloped roofs and depends on slope/surface/thermal regime.

Permit submittal?

Use as an engineering aid; sealed calcs may be required.

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)
\[p_f = 0.7\, C_e\, C_t\, I\, p_g \\]
p_f = 0.7\, C_e\, C_t\, I\, p_g \
Formula (extracted LaTeX)
\[p_s = C_s\, p_f \\]
p_s = C_s\, p_f \
Formula (extracted text)
Flat roof snow load: \\[ p_f = 0.7\, C_e\, C_t\, I\, p_g \\] Optional balanced sloped roof load: \\[ p_s = C_s\, p_f \\]
Formula (extracted text)
\\( p_f = 0.7 \times 1.0 \times 1.0 \times 1.0 \times 30 = 21 \text{ psf} \\) If Cs = 0.9, then \\( p_s = 0.9 \times 21 = 18.9 \text{ psf} \\).
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