1. What is Flat Roof Snow Load?

The flat roof snow load is the downward force on a flat roof by the weight of accumulated snow and ice. The Ontario Building Code provides specific requirements for snow load calculations to ensure structural safety during winter months.

2. How Does the Calculator Work?

The calculator uses the Ontario Building Code formula:

Where:

• \( S \) — Snow load on roof (kPa)
• \( I_s \) — Importance factor for the building
• \( S_s \) — Ground snow load (kPa)
• \( C_b \) — Basic roof snow load factor
• \( C_w \) — Wind exposure factor
• \( C_s \) — Slope factor
• \( C_a \) — Accumulation factor
• \( S_r \) — Associated rain load (kPa)

Explanation: The equation accounts for local snow conditions, building importance, and roof characteristics.

3. Importance of Snow Load Calculation

Details: Proper snow load calculation is crucial for structural integrity, preventing roof collapse, and ensuring building safety during winter conditions in Ontario.

4. Using the Calculator

Tips: Enter ground snow load and roof snow load in kPa, select appropriate importance factor and basic roof factor. Consult the Ontario Building Code for specific values for your location.

5. Frequently Asked Questions (FAQ)

Q1: Where can I find ground snow load for my area?
A: Ground snow load values are provided in the Ontario Building Code Supplement or can be obtained from local building authorities.

Q2: What is a typical basic roof factor (C_b)?
A: For flat roofs, the basic factor is typically 0.8, but may vary based on roof characteristics.

Q3: How does importance factor affect the calculation?
A: More important buildings (like hospitals) use higher factors to provide additional safety margin.

Q4: Should I consider drifting snow?
A: This calculator provides basic flat roof loads. Special conditions like drifting require additional calculations.

Q5: Is this calculator suitable for all roof types?
A: This is specifically for flat roofs. Sloped roofs require different calculations.