Are risers required at wood deck stairways

[j.Peter Buss]

Are risers required at wood deck stairways ? If so is this a code issue in chicago ?

Thanks
Peter Buss

[David Banks]

Are risers required at wood deck stairways ? If so is this a code issue in chicago ?

Thanks
Peter Buss

Are you under IRC?
2003 IRC. R311.5.3.3 Last sentence.
Open risers are permitted, provided that the opening between treads does not permit the passage of a 4- inch diameter sphere.