Structural, Civil & MEP Engineering Services in Illinois

Illinois has a licensing rule that catches out almost every out-of-state firm: structural engineering here requires an Illinois Structural Engineer licence, and an Illinois PE may not perform structural design. Get that wrong and the seal on your drawings is worthless. We assign the correct licence type from the start, and most standard packages are sealed in 48–72 hours.

Engineering Projects Delivered

0 +

Illinois Counties Covered

Typical Sealed Turnaround

0 Hrs

Licensed PE Review

0 %

The Codes We Design To in Illinois

Illinois has no single statewide building code book. Adoption happens locally, but a recent state law now sets a floor — and Chicago runs an entirely separate system.

Statewide ICC Minimums

Public Act 103-0510 requires every municipality and county that has a building code to meet ICC minimums using one of the last three code cycles. It sets a floor, not a single uniform code.

Chicago Construction Codes

Chicago runs its own Title 14B based on the 2018 IBC, mandatory since August 2020, plus the Chicago Energy Transformation Code. A set prepared to the state baseline will not satisfy a Chicago review.

Illinois Energy Conservation Code

The 2021 IECC with Illinois amendments took effect 1 January 2024 and applies statewide, with the residential provisions preempting home rule. An optional Stretch Energy Code exists for municipalities that adopt it.

SE Licence Required for Structural

This is the critical one. Illinois maintains a separate Structural Engineer licence, and structural design must be performed under it. An Illinois PE licence does not cover structural work, and no out-of-state PE licence substitutes for it.

Separate Plumbing & Accessibility Codes

The Illinois Plumbing Code is administered by the Department of Public Health and the Illinois Accessibility Code is separate from the building code. Both are checked at submittal.

Home Rule Variation

Home rule municipalities set their own adopted editions, so Aurora, Naperville, Joliet and Rockford can each differ. We confirm the governing edition for your address before design.

Design Conditions That Actually Govern in Illinois

Illinois runs from the Chicago lakefront to the New Madrid seismic zone in the far south, and the governing conditions change considerably along the way.

Seismic Design Category generally A to B in northern Illinois, rising to C or D in the far south
New Madrid Seismic Zone influence across southern counties, which surprises many designers
Ground snow loads around 25 to 30 psf across northern Illinois
Frost depth of approximately 42 inches in the Chicago area, driving footing depth
Lake-effect exposure and wind conditions along the Lake Michigan shoreline
Chicago Energy Transformation Code requirements on projects within the city
Expansive and compressible soils across parts of the central and southern state
County stormwater ordinances, notably in Cook, DuPage and Lake counties

Who Seals Your Drawings in Illinois

Illinois is the state where getting this wrong is most costly. Structural engineering services require an Illinois Structural Engineer licence issued by the Department of Financial and Professional Regulation — an Illinois Professional Engineer licence does not cover structural design, and no out-of-state PE licence substitutes for it. Civil and MEP work is sealed by an Illinois-licensed PE. We assign the correct licence type for your scope and confirm the named engineer of record on your quote.

Engineering Services We Deliver Across Illinois

Structural Engineering

Framing, foundations and retaining walls with sealed load calculations to the Illinois code edition your jurisdiction enforces.

Civil & Site Engineering

Site plans, grading and drainage, stormwater, utilities and paving prepared for Illinois permit submittal.

MEP Engineering

HVAC, electrical and plumbing design with the load calculations and energy compliance forms Illinois reviewers ask for.

Review & PE Stamp

Have drawings already? A Illinois-licensed engineer reviews them against local code and applies the seal.

Illinois Cities and Jurisdictions We Serve

We prepare and seal permit drawings across Illinois, including projects reviewed under the Chicago Construction Codes.

How We Protect Illinois Clients Before You Spend a Dollar

Engineering is bought on trust long before it is bought on price. These are the commitments every Residential PE engagement carries, in writing, from the first message.

Free Quote, One Fixed Fee

Consultations and quotes cost nothing. You receive one written fixed fee against a written sheet list — no hourly billing, no surprise add-ons.

A Named Engineer of Record

Every drawing is sealed by a professional engineer holding an active licence in your project’s state, and we confirm who that engineer is before you commit.

Revisions Until Approval

If the plan reviewer returns comments, we revise the sealed drawings and respond as part of the original fee — never as a change order.

Your Documents Stay Private

Drawings, surveys and site information are used only to engineer your project. They are never resold, published or used as portfolio material without consent.

48–72 Hour Turnaround

Most standard packages are sealed and returned within two to three business days, so engineering is never the reason a permit slips.

A Real Engineer Answers

Questions reach an engineer, not a call centre. Open the live chat and you are talking to someone who can actually scope and price the job.

Getting Illinois Permit Drawings Sealed

Send Your Project

Share the Illinois project address, your plans or sketches, and any comments the building department has already issued.

Free Fixed-Fee Quote

We confirm the governing Illinois code edition, the sheet list and the schedule, then return a written fixed fee at no cost.

Design & PE Review

Our engineers produce the design and calculations, then an engineer licensed in Illinois reviews the package before anything is sealed.

Sealed & Submitted

You receive sealed, signed PDFs formatted for your Illinois building department, plus support through plan-review comments.

Illinois Engineering Questions We Are Asked Most

Do I need a Structural Engineer or a Professional Engineer in Illinois?

For structural design, an Illinois Structural Engineer (SE) licence is required. Illinois is unusual in maintaining a separate SE licence, and an Illinois PE licence does not authorise structural design work — nor does a PE licence from another state. For civil and MEP work an Illinois-licensed PE is correct. We assign the right licence type for your scope so the seal is actually valid.

Which building code applies to my Illinois project?

It depends on your municipality. Illinois has no single statewide code book, though Public Act 103-0510 now requires local codes to meet ICC minimums from one of the last three cycles. Chicago is entirely separate, running its own Title 14B based on the 2018 IBC. We confirm the governing edition for your address before design starts.

Is Chicago different from the rest of Illinois?

Substantially. Chicago maintains its own Chicago Construction Codes and its own Energy Transformation Code, with its own review process. Drawings prepared to the state baseline will not satisfy a Chicago submittal, so we prepare Chicago projects to Title 14B specifically.

Does southern Illinois really need seismic design?

Yes. The New Madrid Seismic Zone raises seismic design categories across the far southern counties to levels comparable with parts of the west coast. It is one of the most commonly missed requirements in the state because designers assume the Midwest is seismically quiet.

What energy code applies?

The Illinois Energy Conservation Code, based on the 2021 IECC with Illinois amendments, effective 1 January 2024 and applying statewide — the residential provisions preempt home rule. Chicago projects follow the Chicago Energy Transformation Code instead. Some municipalities have also adopted the optional Stretch Energy Code.

How deep do footings need to be?

Frost depth in the Chicago area is approximately 42 inches and is set locally, so footings must bear below that. It is deeper than many out-of-state designers expect and it changes both the foundation cost and the excavation plan.

How fast can I get sealed Illinois drawings?

Most standard residential and light commercial packages are returned within 48 to 72 hours of receiving complete information. Chicago submittals and projects requiring county stormwater review are quoted with a realistic schedule.

What does it cost?

We quote a fixed fee per project rather than an hourly rate, based on scope and your municipality’s submittal requirements. Quotes are free and usually returned the same business day — see our pricing page.

We Also Seal Drawings Across The Midwest

Projects rarely stop at a state line. We hold coverage in all 50 states and assign every project to an engineer licensed where it is permitted — these are the neighbouring states we work in most often.

Get a Fixed-Fee Quote for Your Illinois Project

Send your Illinois site information and we will confirm the sheet list, the engineer of record licensed in Illinois and a firm price — usually the same business day, at no cost.