The Maximum Inclination of Residential Stairs

Dimensions

• The angle of the incline for residential stairs is usually 30 degrees. This angle is typically determined by the riser height and tread depth. The tread of stairs refers to the depth of the area where people step, and the riser is the height of each step. Different areas will have different building codes that specify the use of the riser and tread to equal the angle. The maximum, though, in residential situations will be around 30 degrees.

Benefits

• Building residential stairs at a safe angle will keep residents safer in one of the most dangerous areas of the home. The Cornell University Cooperative Extension reports that the majority of household accidents were falls, many of which took place on the stairs. The majority of falls occur when people are walking down the stairs, and a steep slope could contribute to more accidents.

Considerations

• Every state, county or city has different building codes to determine the angle of residential stairs. Check your local building office to determine if your area differs from 30 degrees. Commercial and industrial buildings often have stairways with less steep angles than 30 degrees. This is because these stairwells are used by more people, and they need to keep more people safe than those stairwells used in a typical residential home.

Adding Handrails

• Even though residential situations aren’t often as dangerous as commercial settings, many town building codes still require a handrail for residences. Usually, there is a maximum number of steps a home is allowed to have before a handrail is required. For instance, if a home is required to have handrails for stairwells with more than four stairs, the builder could still add a few steps leading from room to room without worrying he’s violating building codes. If a home is being built for a handicapped or elderly person, though, it could still make sense to add a railing, even for stairwells that have only a few steps and are typically added for aesthetics. Cornell found that stairways with just one or two steps accounted for a high number of falls. If possible, design homes without these steps.