Minimum Roof Snow Loads in the Denver Area

In the state of Colorado, we have to deal with reasonably heavy minimum Denver snow loads when we track loads from the roof of a building to the ground. In a lot of cases, structural engineers need to us minimum snow loads given by a given jurisdiction. When snow loads are generally calculated, we use the code minimum reductions given by the current American Society of Civil Engineers code. In this calculation process, there are two loads that are used to apply to a roof. There is a flat roof snow load Pf, and a sloped roof snow load Ps. Now, generally we can use these loads for a design of a residential structure, but in the cases when we have a minimum flat or sloped roof snow load given by a jurisdiction, we need to use these loads instead of the reduced loads we have calculated. For example, if we have a minimum flat roof snow load Pf that we need to use, the only reduction that we can use is a sloped factor Cs given from chapter 7 in ASCE 7. Another situation is when we have to use a minimum sloped roof snow load Ps, and this means that we basically have no reductions that we can use in our design for snow loads. This is one of the challenges that engineers face when designing a residential house in the greater Denver area.

Heavy Roof Snows