Charleston County, SC Building Setbacks & Zoning: Lot Coverage Limits (2026)
Key Facts
- R-4 building cover
- 30% of lot
- AGR building cover
- 30% of lot
- Includes
- Buildings, roofs, pools (no decking)
- Impervious limit
- Per county Stormwater Manual
- Code section
- ZLDR §4.2.5; Tables 4.10.3, 4.79.3
Summary
In both the R-4 Single Family Residential and rural AGR districts, maximum building coverage is 30% of the lot. Coverage counts principal and accessory buildings, roofed areas, and swimming pools (excluding pool decking). Impervious surface is separately governed by the county Stormwater Manual.
Building coverage refers to the area of a Lot covered by Buildings (Principal and Accessory) or roofed areas, as measured along the outside wall at ground level, and including all projections, other than fire escapes, canopies and the first two feet of a roof overhang. Swimming pools (excluding the pool decking) shall be included in Building Coverage.
Full Breakdown
ZLDR §4.2.5 defines building coverage as the percentage of a lot covered by principal and accessory buildings and roofed areas, measured along the outside wall at ground level, including all projections except fire escapes, canopies, and the first two feet of roof overhang; swimming pools (minus decking) are included. Table 4.10.3 (R-4) and Table 4.79.3 (AGR) both cap maximum building cover at 30% of the lot. Total impervious surface is limited separately under the current Charleston County Stormwater Manual, which matters on low-lying, flood-prone, and sea-island parcels.
Violations & Fines
Exceeding maximum building or impervious coverage without a variance is a violation; permits may be denied and stormwater review can require redesign or a zoning variance.
Frequently Asked Questions
How much of my lot can I build on?
Does my pool count toward coverage?
Sources & Official References
Other rules in Charleston County
Compare Charleston County to another location·View the South Carolina building setbacks & zoning overview
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