Snow Load Weight Calculator

About Snow Load Weight Calculator (Formula)

A Snow Load Weight Calculator is an essential tool for engineers, architects, and builders working in regions prone to heavy snowfall. Snow loads can significantly impact the structural integrity of buildings and other structures, making it critical to calculate and account for the weight of accumulated snow. This calculator helps determine the potential snow load on a roof or any structure, ensuring its safety and compliance with building codes and standards.

The formula for calculating snow load weight varies depending on factors such as location, roof shape, and snow load design criteria. The most commonly used formula in the United States is based on the Uniform Building Code (UBC) and the International Building Code (IBC). It is expressed as follows:

Snow Load (SL) = Pf x Cf x Ie x Ct x Is x S


  • Pf represents the ground snow load, which is determined based on geographic location and is usually provided by local building codes or meteorological data.
  • Cf is the roof shape factor, accounting for the slope and shape of the roof.
  • Ie is the thermal factor, which considers the effect of building insulation on snow accumulation.
  • Ct is the temperature factor, accounting for temperature variations.
  • Is is the snow exposure factor, which considers wind effects on snow accumulation.
  • S is the tributary roof area, typically measured in square feet or square meters.

Let’s explore each of these factors in more detail:

  1. Ground Snow Load (Pf): This value is specific to the location and is determined by analyzing historical snowfall data and regional climatic conditions.
  2. Roof Shape Factor (Cf): Different roof shapes have varying abilities to shed or retain snow. Steeper roofs, for instance, may accumulate less snow than flat roofs.
  3. Thermal Factor (Ie): This factor accounts for the insulation on the roof, which can affect how quickly snow melts and slides off.
  4. Temperature Factor (Ct): Temperature fluctuations can cause snow to compact and become denser, increasing its weight.
  5. Snow Exposure Factor (Is): This factor considers how exposed the building is to wind, which can redistribute and accumulate snow unevenly.
  6. Tributary Roof Area (S): This is the portion of the roof that contributes to the load on a specific area.

Accurate calculation of snow load is crucial for ensuring the safety of structures, as excessive snow accumulation can lead to roof collapse or structural damage. Compliance with local building codes and standards is essential, and using a Snow Load Weight Calculator simplifies the process, helping professionals make informed decisions in construction and building design. Properly accounting for snow load weight ensures that structures can withstand the rigors of winter weather and provides peace of mind to occupants and owners.