Decks
Call Before Digging
Contact Joint Utility Locating Information for Excavators (JULIE) at 811 prior to digging post holes.
Inspections are required for post holes, rough, and final. For more information, call the Building Department at (847) 223-8515 Monday through Friday, 8 a.m. to 5 p.m.
Permit Application Requirements
- Completed building permit application
- Provide one (1) copy of plat of survey dimensionally locating deck with regards to property lines and any buildings
- Provide two (2) copies of pier and framing plans indicating dimensions and materials (with sizes) to be used in construction
Maximum Deck Joist Spans
Southern Pine
| Joist Size | 12-inch O.C. | 16-inch O.C. | 16-inch O.C. |
|---|---|---|---|
| 2 by 8 | 13 feet - 1 inch | 11 feet - 10 inch | 9 feet - 8 inches |
| 2 by 10 | 16 feet - 2 inches | 14 feet - 0 inches | 11 feet - 5 inches |
| 2 by 12 | 18 feet - 0 inches | 16 feet - 6 inches | 13 feet - 6 inches |
Douglas Fir-Larch, Hemplock-Fir, SPF
| Joist Size | 12-inch O.C. | 16-inch O.C. | 16-inch O.C. |
|---|---|---|---|
| 2 by 8 | 12 feet - 1 inch | 11 feet - 1 inches | 9 feet - 1 inch |
| 2 by 10 | 15 feet - 8 inches | 13 feet - 7 inches | 11 feet - 1 inch |
| 2 by 12 | 18 feet - 0 inches | 15 feet - 9 inches | 12 feet - 10 inches |
Redwood, Western Cedars, Ponderosa Pine, Red Pine
| Joist Size | 12-inch O.C. | 16-inch O.C. | 16-inch O.C. |
|---|---|---|---|
| 2 by 8 | 11 feet - 8 inches | 10 feet - 7 inches | 8 feet - 8 inches |
| 2 by 10 | 14 feet - 11 inches | 13feet - 0 inches | 10 feet - 7 inches |
| 2 by 12 | 17 feet - 5 inches | 15 feet - 1 inch | 12 feet - 4 inches |
Handrails and Guardrails
Porches, balconies, or raised floor surfaces located more than 30 inches above the floor or grade below shall have guardrails not less than 36 inches in height.
Open sides of stairs with a total rise of more than 30 inches above the floor or grade below shall have guardrails not less than 34 inches in height measured vertically from the nosing of the treads.
Required guardrails on open sides of stairways, raised floor areas, balconies, and porches shall have intermediate rails or ornamental closures which will not allow passage of an object four inches or more in diameter. Horizontal spacing between the vertical members in required guardrails shall be a maximum of four inches at the nearest point between the members.
(This is information only and does not contain all requirements for construction).
Notes:
- All structural lumber, beams, wood deck flooring, and other appurtenances shall be constructed of lumber that is preservative-treated.
- Framing and fasteners/connections shall comply with the International Residential Code/2009.
- Piers shall be a minimum of eight (8) inches in diameter of poured concrete, with level bottom, forty two (42) inches below grade, framed up a minimum four (4) inches above finished grade.
- 5/4 inch by 6 inch deck boards should not span more than 16".
- Cantilever shall not extend more than two (2) feet with a ratio three (3) feet in to one (1) foot out.