Friday, June 5, 2009

Handrail Code Items

Handrail codes have relaxed over the years to allow for a variety of shapes and sizes. Here are some of the relevant code items for the 2006 Seattle Residential Building Code:

  • Must be positioned 34"-38" when measured vertically above the front of each tread.
  • If installed against a wall, the space between the handrail and the wall may not be less than 1 1/2"
  • Must extend at least from a point directly above the lowest riser to a point directly above the upper riser (it can extend beyond these points). See next bullet point for exception.
  • At the bottom tread, a 'starting newel' is allowed over the lowest tread (meaning the handrail may end a little earlier than above the lowest riser).
  • Handrails must return to wall or to newel post.
  • For the actual handrail you have two choices:

    Type 1: Handrails with a circular cross section must have a diameter between 1 1/4" - 2". If the handrail is not circular, the perimeter dimension must be at least 4" and not greater than 6 1/4" with a maximum cross section dimension of 2 1/4".

    Type 2: Handrails with a perimeter greater than 6 1/4" shall provide a graspable finger recess area on both sides of the profile. The finger recess shall begin within a distance of 3/4" measured vertically from the tallest portion of the profile and achieve a depth of at least 5/16" within 7/8" below the widest portion of the profile. This required depth shall continue for at least 3/8" to a level that is not less than 1 3/4" below the tallest portion of the profile. The minimum width of the handrail above the recess shall be 1 1/4" to a maximum of 2 3/4". Edges shall have a minimum radius of .01".

Thursday, June 4, 2009

Railing Code Items

Many people ask about common items like what are the code requirements for a stair railing. Here are some relevant code items from the 2006 Seattle Residential Code.
  • The top of the railing needs to be a minimum of 34" measured vertically above the nosing of the stair tread.
  • The triangular opening formed by a stair tread, riser, and the bottom railing of the guard rail cannot let a 6" sphere pass through.
  • The railing should not let a 4" sphere pass through any opening (except as noted above).
  • The 'pickets' in the railing can be vertical or horizontal, or follow the slope of the stairs (or every which direction as long as the 4" rule is maintained.)
  • Connections of the railing to the structure should resist 200lb/sf load.
  • A handrail is required too.