Ohio adopts the Residential Code of Ohio (RCO) for one-, two-, and three-family dwellings. The RCO is based on the International Residential Code (the 2019 RCO uses the 2018 IRC as its basis). Emergency escape and rescue openings are addressed in Section R310.
Your city or township may amend or interpret these rules. Use the figures below as a planning baseline, then confirm with the building department that issues your permit.
Opening size baselines (IRC / RCO R310)
A 24″ × 20″ opening is only about 3.3 ft². You need the minimum height and width and the total clear area.
Window wells (area wells)
- Minimum floor area about 9 square feet
- Minimum projection and width about 36 inches
- Wells deeper than 44 inches need a permanent ladder or steps
- Covers/grates must open from inside without keys, tools, or special knowledge
Where to confirm locally
Start with your city building department. Examples we verified for major suburbs:
- Dublin - City of Dublin Division of Building Standards
- Westerville - City of Westerville Building Division (Planning and Development)
- Hilliard - City of Hilliard Building Standards Division
- Grove City - Grove City Building & Zoning
- Upper Arlington - City of Upper Arlington Building Division
- Gahanna - City of Gahanna Division of Building
- Reynoldsburg - City of Reynoldsburg Building Department
- Pickerington - City of Pickerington Building Department
Also see the Ohio Board of Building Standards for statewide RCO information.
Related
Sources: Ohio Board of Building Standards materials on the 2019 Residential Code of Ohio (IRC 2018 basis); IRC Section R310 emergency escape opening dimensions as summarized in published code tip sheets. Confirm the edition your jurisdiction enforces.