Most renovation problems that show up a year after move-in are not workmanship problems. The drywall seam that cracks every winter, the hardwood floor that developed a hump along the old wall line, the pocket door that will not latch, the sag you can see when you sight down the new beam: these are load paths that were never worked out on paper. The contractor framed what looked right, the inspector checked what the code let him check, and the house has been quietly redistributing weight ever since.
This post explains when a Georgia renovation needs engineered structural design, what a complete set of framing and foundation plans actually contains, and how Mack Engineering and our sister company Mack Development handle the design, the engineering and, if you want it, the construction.
Key takeaways
- Georgia adopted the 2024 International Residential Code with state amendments effective January 1, 2026. Any element that falls outside the IRC’s prescriptive tables must be engineered.
- The IRC’s deflection limits (L/360 for floors and for members supporting drywall) are the line between a floor that feels solid and one that cracks finishes. Undersized beams can pass a visual inspection and still fail that limit.
- A complete renovation package is a framing plan, a foundation plan, connection details and a load-path narrative. A beam size scribbled on the permit drawing is not a structural design.
- Mack Engineering produces the design and engineering. Mack Development can build it, or your builder can.
When Georgia code requires an engineer
The Georgia Department of Community Affairs adopted the 2024 editions of the International Residential Code, International Building Code and related codes, with Georgia amendments, effective January 1, 2026 (Georgia DCA code adoption memo). The IRC is written so that a conventional house can be framed from its tables without an engineer. The same code is explicit about the exception: where a building of otherwise conventional construction contains structural elements that exceed the limits of Section R301 or otherwise do not conform to the code, those elements must be designed in accordance with accepted engineering practice (IRC R301.1.3, summarized by Gold GCP). In renovation work that exception is the rule. Removing a bearing wall to open a kitchen, carrying a second floor on a new beam, adding a story over an existing foundation, cantilevering a bump-out, or setting a point load from a ridge beam onto an existing slab all leave the prescriptive tables behind. The Georgia building codes we design to are the starting point; the engineering is what makes a non-prescriptive condition permittable.
A note on what the law requires versus what the permit office requires. Georgia’s engineering practice act exempts certain work from the professional-engineer licensing requirement (O.C.G.A. § 43-15-29; Georgia PELS Board summary). That exemption does not relieve the design from meeting the code, and in our experience North Georgia building departments routinely ask for sealed engineering on beams, headers and foundations that fall outside the IRC tables. If your plans examiner asks for a stamp, the exemption is not an argument that will get your permit issued.
What goes wrong when the structure is not engineered
The failure mode is almost never collapse. It is deflection and movement that the finishes cannot tolerate. The IRC limits floor joist deflection to L/360 of the span under live load and L/240 under total load; for a 15-foot joist that is about half an inch (IRC 2024 floor joist span tables, Jaspector). Headers and beams supporting drywall or plaster are held to the same L/360 limit, and the consequence of exceeding it is spelled out in plain terms: doors stick or fail to latch, windows rack out of square and drywall cracks around the opening (IRC 2024 header sizing, Jaspector). Removing a bearing wall without a properly sized beam, posts and support below is described in the structural literature as one of the most common causes of residential distress, with sagging above the opening as the first visible sign (EngineersUniverse, load-bearing walls).
Three patterns account for most of the renovation calls we get:
- The beam is close but not right. A contractor sized a flush LVL from a supplier’s chart for a uniform load, but the beam is actually picking up a point load from a post above. It carries the load; it also deflects enough to crack the ceiling joint every heating season.
- The load got to the beam but not to the ground. New posts land on a floor system or a slab that was never designed for a concentrated load. The floor humps or dips along the old wall line, hardwood cups and squeaks, and the crack in the slab tells you where the footing should have been.
- The existing structure was assumed, not checked. A second-story addition goes on a 1990s foundation and wall system sized for one floor. Nothing fails, but the whole house now rides closer to its limits and every finish shows it.
Each of these is cheap to prevent on paper and expensive to correct after drywall.
What a complete structural package includes
When Mack Engineering is retained on a renovation, the deliverable is a set of drawings a framer can build from and a plans examiner can approve without a round of comments. It includes:
- Existing-conditions review. We field-verify the framing, bearing lines, foundation type and anything concealed that the plan depends on. Assumptions get written on the sheet so the builder knows what to confirm when walls are open.
- Framing plans. Floor and roof framing for every affected level, with member sizes, species and grade or engineered-lumber designation, bearing points, hangers and connectors, and the load path called out from roof to foundation.
- Foundation plan. New footings, pad sizes and reinforcing for every new point load, slab thickening where posts land on existing concrete, and any underpinning or wall modifications.
- Details and schedules. Beam-to-post and post-to-footing connections, hold-downs, shear wall or bracing where a wall removal affects lateral capacity, and a header schedule for new openings.
- Calculations and seal. Load takedown, member checks against strength and deflection, and the engineer’s seal where the jurisdiction requires it.
For larger projects we build the model in Revit, which is how we catch the beam that lands in the middle of the HVAC trunk before anyone cuts it in the field. Our Revit modeling and BIM coordination page describes that workflow, and our post on how coordinated plans produce coordinated costs explains why it saves money. On design-build projects, the same model feeds Mack Development’s 3D design so you can walk the new space before it is framed.
Which engineer do you need
Homeowners often ask whether they need a structural engineer or a civil engineer. For an interior wall removal or an addition that stays on the existing footprint, structural is the answer. If the addition expands the footprint, adds impervious surface, changes the drainage pattern or sits near a stream buffer or septic field, the civil side comes into play as well, and our firm covers both under one roof.
From plans to a finished renovation
Mack Engineering can stop at the stamped plans. Many of our renovation clients hand the set to their own contractor, and we stay available for the inevitable field question when a wall is opened and the framing is not what anyone expected. Where a project warrants it, we also provide owner’s-side construction management so the engineering intent is actually built.
Or we can carry it all the way through. Our sister company, Mack Development builds the renovation under the same ownership and the same drawings. Mack Development is a licensed residential contractor in Georgia and North Carolina, follows a published five-step design-build process and backs its work with a ten-year structural warranty. You can read their reviews on their site. The point of the arrangement is simple: the people who engineered the beam are in the same meetings as the people installing it.
Frequently asked questions
If the new beam, posts and footings fall outside the IRC’s prescriptive tables, which they usually do once point loads are involved, IRC R301.1.3 requires engineered design. Most North Georgia building departments ask for sealed drawings for beam and footing work. Call your permit office before you demolish anything.
A permit drawing shows what is being built. A framing plan shows how it stands up: every member size, bearing point, connector and footing, with the load path traced to the ground and calculations behind each size. Plans examiners can approve the second; they often send the first back with comments.
Recurring cracks at the same location almost always indicate movement, most often a beam or joist deflecting beyond the L/360 limit the code sets for members supporting drywall, or a post bearing on a floor or slab that was not designed for the load. The fix is structural, not cosmetic.
Yes. We deliver a complete set your contractor can build from and permit, and we stay available for field questions. Design-build through Mack Development is an option, not a condition.
Planning a renovation that moves walls, adds a floor or opens up a kitchen? Contact Mack Engineering or call (770) 715-7295 to schedule a structural review. We will tell you what needs engineering and what does not.
Related reading
- Structural vs Civil Engineer Georgia: Which Do You Need?
- Engineering Firm That Knows Georgia Construction Codes
- Revit Modeling & BIM Coordination Services
- Coordinated Plans, Coordinated Costs
- Construction Management Services
- The Custom Home Building Process (Mack Development)
- Our 5-Step Design-Build Process (Mack Development)
- 3D Home Design in Autodesk Revit (Mack Development)
- Client Reviews (Mack Development)
Sources
- Georgia Department of Community Affairs, New Codes and Amendments Effective January 1, 2026 (memo)
- IRC R301.1.3 Engineered design, summarized in Gold GCP, Structural Coordination
- Jaspector, IRC 2024 Floor Joist Span Tables (R502.3; L/360 live load, L/240 total load)
- Jaspector, IRC 2024 Header Sizing (deflection limits and consequences for finishes)
- O.C.G.A. § 43-15-29, Exceptions to operation of chapter (Justia)
- Georgia State Board of Professional Engineers and Land Surveyors, Professional Engineer Information, Exemptions from Licensure
- EngineersUniverse, What Is a Load-Bearing Wall (consequences of unsupported removal)
- Mack Development Group, Custom Build and Process pages (licensed GA/NC, ten-year structural warranty, five-step process)
This article is general information, not a site-specific engineering opinion. Code requirements and local ordinances change; confirm current requirements with the authority having jurisdiction for your property.