by Jerry Peck - Codeman on Tue Oct 18, 2011 6:21 pm
While many AHJ do not include retaining walls and exterior away-from-the-house-stairs, many other AHJ do include those items as the code does address both. Thus the walking surface next to the retaining wall would require a railing on the retaining wall if there is more than a 30 inch drop to the grade below.
From the IRC:
The retaining walls and exterior away-from-the-house-stairways fall within the definition of accessory structures:
- ACCESSORY STRUCTURE. A structure not greater than 3,000 square feet (279 m2) in floor area, and not over two stories in height, the use of which is customarily accessory to and incidental to that of the dwelling(s) and which is located on the same lot.
Accessory structures are included within the scope of coverage of the IRC: (bold and underlining are mine)
- R101.2 Scope. The provisions of the International Residential Code for One- and Two-family Dwellings shall apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, removal and demolition of detached one- and two-family dwellings and townhouses not more than three stories above-grade in height with a separate means of egress and their accessory structures.
Guards are required where the floor or grade is more than 30 inches above the floor or grade below:
- R312.1 Guards. Porches, balconies, ramps or raised floor surfaces located more than 30 inches (762 mm) above the floor or grade below shall have guards not less than 36 inches (914 mm) in height. Open sides of stairs with a total rise of more than 30 inches (762 mm) above the floor or grade below shall have guards not less than 34 inches (864 mm) in height measured vertically from the nosing of the treads.
Porches and decks which are enclosed with insect screening shall be equipped with guards where the walking surface is located more than 30 inches (762 mm) above the floor or grade below.
Technically, all AHJ should be including those accessory structures, but not all do. Your AHJ is apparently one of the AHJ who has read and understands what the code is saying regarding the scope of the IRC and to what it is to be applied, i.e., the code "shall apply to ... detached one- and two-family dwellings and townhouses ... and their accessory structures".
Jerry Peck - CodeMan
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Construction Litigation Consultant - Retired
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