A civil engineer designs everything outside the building envelope: grading, drainage and detention, erosion control, utilities, septic, roads, and the permit plan sets a jurisdiction reviews. A structural engineer designs the load-carrying parts of the building itself: footings, foundations, beams, headers, framing, and retaining wall structures. In Georgia both are licensed professional engineers, but “professional structural engineer” is a separate registration under state law, and specific “designated structures” (Risk Category III or IV buildings, buildings 100,000 square feet or larger, occupied floors 45 feet or more above average grade, and others) require that separate credential. If your question is about water, dirt, permits, or the site, start with a civil engineer. If it is about whether the building stands up, start with a structural engineer.
The question behind the question
When someone searches “structural engineer near me,” they usually have one of about six real problems: a cracked foundation, a sagging floor, a wall they want to remove, a home inspection that flagged something, a retaining wall that is leaning, or a permit reviewer who told them they need an engineer’s letter. Only some of those are structural.
Meanwhile, the people who search “civil engineer near me” often actually need a structural letter, and the people searching for structural help often need drainage fixed. This post exists to sort that out before you pay the wrong consultant.
Straight comparison
| Question you have | Discipline | Typical deliverable |
|---|---|---|
| Water is pooling / running onto my property | Civil | Drainage study, grading plan, drainage improvement design |
| I need a land disturbance permit | Civil | LDP plan set, erosion and sediment control plan, hydrology study |
| I need to know if this lot is buildable | Civil | Feasibility report, site diligence |
| I need a detention pond or stormwater approval | Civil | Hydrology study, detention design |
| I need septic or sewer for a lot | Civil | Soil coordination, septic or sewer design |
| I want to remove a load-bearing wall | Structural | Framing plan, beam and header sizing, sealed letter |
| My foundation is cracked or settling | Structural | Inspection report, repair design |
| I need a footing or foundation design for an addition | Structural | Foundation plan |
| I need a retaining wall over 4 feet | Both | Wall structural design plus civil grading and drainage |
| The county wants an engineer’s letter on my as-built | Depends | Read the comment letter; it names the discipline |
What Georgia law actually says
Under O.C.G.A. § 43-15-2, structural engineering is defined as the practice of a specialized branch of professional engineering involving the design or analysis of designated structures as defined by the board, including consultation, investigation, evaluation, planning, designing, analyzing, and responsible supervision of construction or operation, where the public welfare or the safeguarding of life, health, or property is involved (Georgia PELS laws and rules).
A “professional structural engineer” is a professional engineer with specialized knowledge in structural engineering who holds a current certificate of registration as a professional structural engineer from the Georgia Professional Engineers and Land Surveyors Board. Georgia also directs applicants whose experience is in structural engineering to sit the two-component, 16-hour NCEES Structural exam (Georgia Secretary of State).
“Designated structures”: where the SE credential becomes mandatory
For buildings requiring a building permit under the adopted International Building Code with current Georgia Amendments, a designated structure includes any building meeting one of the following:
| Trigger | Threshold |
|---|---|
| Risk category | Risk Category III or IV under IBC Table 1604.5 |
| Covered gross area | 100,000 square feet or greater |
| Occupied floor elevation | 45 feet or more above average ground level |
| Lateral system aspect ratio | Height-to-least-width ratio of 7 or greater |
| Analysis method | Nonlinear time-history analysis or special seismic energy-dissipation systems |
For bridges and transportation structures, designated structures include complex bridges: spans longer than 300 feet, tunnels, cable-stayed bridges, suspension bridges, movable bridges, trusses with spans longer than 300 feet, and arch bridges (Georgia PELS laws and rules).
A custom home, a retail pad, a small office, a warehouse under 100,000 square feet, or a residential retaining wall generally does not hit those triggers. That does not mean you can skip engineering. It means the work can be sealed by a professional engineer competent in that area rather than requiring the separate SE registration.
Cost expectations in Metro Atlanta
| Service | Typical range |
|---|---|
| Residential structural inspection with letter or report | $500 – $1,500 |
| Beam / header design for a wall removal | $750 – $2,500 |
| Foundation design for an addition | $1,500 – $4,000 |
| Residential drainage study and grading design (civil) | $2,500 – $6,000 |
| Site feasibility report (civil) | $3,500 – $8,000 |
| Land disturbance permit plan set (civil) | $8,000 – $30,000+ depending on acreage and jurisdiction |
Ranges are Metro Atlanta planning figures for scoping conversations, not quotes. Our full civil pricing discussion lives in our post on what a civil engineer costs in Metro Atlanta.
How Mack Engineering handles this
We are a civil engineering firm. Site work (grading, drainage, detention, erosion control, utilities, septic coordination, feasibility, zoning exhibits, permit plan sets, and construction management) is what we do and what we seal.
When a project needs structural design or a structural evaluation, we say so and coordinate with a structural engineer rather than stretching our scope. On a retaining wall, an ADU foundation, or a mixed-use pad, that coordination is the value: one team holding the site design, the grading, and the structural interface together so the two plan sets actually agree at the permit counter.
Frequently asked questions
Civil engineering covers the site: grading, stormwater, erosion control, utilities, septic, roads, and permit plans. Structural engineering covers the building’s load path: foundations, framing, beams, and connections.
Structural engineering is a specialized branch of professional engineering. In Georgia a “professional structural engineer” holds a separate certificate of registration from the Professional Engineers and Land Surveyors Board.
For “designated structures,” which include buildings in Risk Category III or IV of IBC Table 1604.5, covered gross area of 100,000 square feet or greater, occupied floor elevation 45 feet or more above average ground level, a lateral system height-to-least-width ratio of 7 or greater, or designs using nonlinear time-history analysis or special seismic energy-dissipation systems.
A civil engineer. Drainage, grading, and stormwater are civil scope.
A structural engineer.
Usually both. The wall structure is structural design; the grading, drainage behind the wall, and local permitting are civil.
Related reading
- When you need a civil engineer vs. a land surveyor in Georgia
- What does a civil engineer actually do?
- Civil engineering in Alpharetta, GA
- Detention Pond Design in Metro Atlanta: GSMM Sizing Criteria, Costs, and Approval Timelines
- Septic System Design in Georgia: Level 3 Soil Reports, Site Limits, and What Actually Kills a Lot
Not sure which one you need? Ask.
Send us the photo, the permit comment letter, or the inspection report. We will tell you which discipline you need, even when the answer is that you do not need us. That is a faster and cheaper conversation than hiring the wrong consultant.