Certificate of Occupancy Plans and Change of Use
Certificate of occupancy plans that prove an existing building is safe for its new use, from occupancy analysis to egress, fixtures and accessibility.
- Stamped by a PE licensed in your state
- Built to IBC, IRC and local amendments
- Plan-check comments answered
Using a building for something new
A building is approved for a specific use. When a warehouse becomes a gym, a house becomes an office, a retail store becomes a restaurant or a barn becomes an event venue, the building department treats it as a change of occupancy and usually requires plans before it will issue a new Certificate of Occupancy. Certificate of occupancy plans show that the building meets the requirements of its new use, even if no walls are moving.
We prepare change of use and CO plan sets for business owners, landlords, brokers and contractors. Each set documents the existing building, identifies the current and proposed occupancy classifications, analyzes what the code requires for the new use and shows the upgrades needed to get there. When your jurisdiction calls for a seal, a Professional Engineer licensed in your state reviews and seals the set.
A change of use often comes with a build-out. When the space also needs new partitions, restrooms or systems, we combine the change of occupancy analysis with full tenant improvement plans so one submittal covers both.
What you receive
- Existing building floor plan
- Occupancy and code analysis sheet
- Egress and life safety plan
- Fire separation and rated assembly details
- Plumbing fixture count and restroom plan
- Accessibility compliance plan
Changes of use we handle
Some of the most common conversions we see each bring a different set of upgrades.
Warehouse to gym or studio
Storage or industrial space converted to fitness, cheer, martial arts or dance use, with higher occupant loads, added exits, restrooms and accessibility upgrades.
Retail to restaurant
Mercantile space converted to food service and assembly seating, with hood, grease interceptor, restroom, egress and fire separation requirements for the new use.
Residence to office or business
Houses converted to professional offices, clinics or salons, moving from residential code to commercial requirements for exits, accessibility and fire protection.
Office to assembly or education
Office suites converted to churches, classrooms, event spaces or daycare, which typically face the largest increase in egress and fire protection requirements.
Agricultural to public use
Barns and agricultural buildings converted to event venues, retail or workshops, often requiring new exits, fire protection, accessible routes and structural review.
New tenant Certificate of Occupancy
Documentation for jurisdictions that require a new Certificate of Occupancy whenever a business changes, even when the use stays in the same occupancy group.
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What certificate of occupancy plans must show
A Certificate of Occupancy confirms that the building official has found a building or space compliant for its intended use. For an existing building with a new use, the plans that support the CO application usually include:
- Code analysis listing the existing and proposed occupancy groups, construction type, building area and height, sprinkler status and occupant load.
- Existing floor plan of the space and the path to the exits, with rooms labeled by their new use.
- Life safety plan showing exits, exit widths, travel distance, exit signs, emergency lighting and fire extinguishers.
- Fire separation plan identifying rated walls, floors and doors between occupancies or tenants.
- Plumbing fixture calculation and restroom layout.
- Accessibility plan covering the route from parking to the entrance, restrooms and primary areas.
- Scope of upgrades needed to bring the space into compliance.
When no construction is needed, the plans may be short. When upgrades are needed, they become a permit set, and the CO is issued after the work passes final inspection. Many jurisdictions also inspect the space with the fire marshal before the CO is issued, and the plans give both inspectors a clear checklist of what they should find on site.
How the code treats a change of occupancy
The International Existing Building Code, which many jurisdictions use for existing buildings, includes specific provisions for a change of occupancy. In broad terms, it compares the hazard of the new use to the old one in several categories:
- Means of egress. A use with more people, such as assembly, needs more exit capacity and often more exits than storage or office use.
- Heights and areas. A higher-hazard use may not be allowed in a building of the existing size and construction type without fire walls or sprinklers.
- Exposure of exterior walls. Walls close to property lines may need to be rated or have openings limited for the new use.
- Fire protection. The new occupancy’s thresholds for sprinklers and fire alarm apply, which can require systems the building never had.
Where the new use is equal or lower in hazard, requirements are lighter. Where it is higher, the building has to meet current code in that category for the new use. Structural loads are checked too: a storage floor converted to assembly, or an office converted to a library or heavy file storage, may carry a different live load than it was designed for, and roofs may receive new equipment. We perform that analysis and document it, so the reviewer sees a reasoned compliance path instead of a list of assumptions.
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- Reviewed by a licensed PE
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Fire separation, egress and fixtures
The three upgrades most often triggered by a change of use are rated separations, egress improvements and restrooms.
Fire separation
When different occupancies share a building, the code either requires fire barriers between them or requires the whole building to meet the stricter rules of both. A restaurant next to a retail store, or a gym inside a multi-tenant warehouse, often needs rated walls, rated doors and protected penetrations between tenants.
Egress
Higher occupant loads mean more required exit width, and above certain loads, additional exits, doors that swing in the direction of travel and panic hardware. We lay out exits and exit paths, and show exit signs and emergency lighting on the life safety plan.
Plumbing fixtures
Required water closets, lavatories and drinking fountains are calculated from the occupant load and occupancy in the plumbing code your jurisdiction uses, the IPC or UPC. A space that needed one restroom as a warehouse may need several as a gym or restaurant. We calculate the requirement, check whether the code allows single-user or family restrooms to count, and coordinate any new restrooms with our plumbing design team.
Zoning, accessibility and the path to a CO
Before the building code questions, there is a zoning question: is the new use permitted at this location? Some uses are allowed outright, some need a conditional or special use permit, and some are not allowed at all. Parking requirements often change with the use, and a restaurant or gym may need more spaces than the previous tenant. We recommend confirming zoning before signing a lease, and we can prepare the site plan your zoning application requires.
Accessibility applies to a change of occupancy as it does to any alteration. The entrance, the route from accessible parking, the restrooms and the primary function areas of the new use generally need to be accessible under ICC A117.1 and the ADA Standards for Accessible Design. Existing buildings often have stepped entrances, narrow doors or small restrooms, and we identify those barriers and design practical solutions.
The path to a CO then follows a familiar order: plans submitted and approved, upgrades built and inspected, fire and building final inspections passed, and the Certificate of Occupancy issued for the new use. If fire alarm devices are part of the upgrade, our fire alarm plans team prepares those drawings with the set. We respond to plan review comments within the original scope at no extra charge.
You likely need CO or change of use plans if
- A new business is moving into an existing space
- A warehouse is becoming a gym or studio
- A house is becoming an office or clinic
- A retail store is becoming a restaurant
- A barn is becoming an event venue
- The city denied your CO or business license
How it works, start to finish
From your first message to stamped drawings, you work directly with the engineering team.
- 1Share your projectSend the address, scope and any drawings, photos or plan-check comments. Two minutes is enough.
- 2Receive a fixed-fee proposalAn engineer reviews the scope and replies with a firm price and delivery date for your change of use & co plans drawings.
- 3Engineering and draftingWe run the calculations and prepare drawings to the codes your jurisdiction enforces, checked before sealing.
- 4Stamped set deliveredYou receive a sealed PDF set ready to submit, and we answer any plan-check comments within scope.
Codes behind a change of occupancy
Change of use and certificate of occupancy plans are prepared to the codes your jurisdiction has adopted, including local amendments:
- International Existing Building Code (IEBC), change of occupancy provisions
- International Building Code (IBC) occupancy classification and egress
- International Fire Code (IFC)
- International Plumbing Code (IPC) or Uniform Plumbing Code (UPC) fixture requirements
- ICC A117.1 and the ADA Standards for Accessible Design
- ASCE 7 live loads where the use changes floor loading
How licensing works. Engineering drawings must be sealed by a Professional Engineer licensed in the state where your project is located. PE Engineer works with a network of state-licensed PEs, so every set is reviewed and stamped by an engineer with an active license in the state where your project is located. Their name and license number appear on the seal, exactly as your building department requires.
Related services
Commercial & Tenant ImprovementCommercial tenant improvement plans with code analysis, egress, accessibility, demolition, partitions and coordinated MEP for retail, office, restaurant and fitness spaces.Explore More
Plumbing DesignWater supply, drain-waste-vent, gas piping and water heater design with fixture unit calculations, prepared to the IPC or UPC and PE sealed.Explore More
Fire Alarm PlansFire alarm device layouts, riser diagrams, battery and voltage drop calculations and sequences of operation, designed to NFPA 72 and PE sealed.Explore MoreFrequently asked questions
What is a Certificate of Occupancy?
A Certificate of Occupancy is the document a building official issues confirming that a building or space complies with the code for its intended use and may be occupied. It is issued after construction or a change of use passes final inspection, and many businesses need it to obtain a business license.
Do I need a new Certificate of Occupancy for a new business?
It depends on the jurisdiction and the use. A change to a different occupancy group almost always requires one. Some cities also require a new CO or occupancy inspection whenever a new business moves in, even with the same use. We check your local rule before you apply.
What is the difference between change of use and change of occupancy?
Change of use is often a zoning term for a different type of business. Change of occupancy is a building code term for a change in occupancy classification or a change in use that brings different code requirements. A project can trigger one, the other or both.
Will my building need fire sprinklers for the new use?
It might. Each occupancy group has its own sprinkler thresholds based on area, occupant load and floor level. Assembly uses such as gyms, restaurants and event spaces most often trigger sprinklers. We analyze your building against the thresholds and tell you early, because sprinklers can affect budget and schedule.
Can I open my business before the CO is issued?
Generally no. Occupying a space before the Certificate of Occupancy is issued can lead to fines or closure orders and can create problems with insurance and business licensing. Some jurisdictions issue a temporary certificate when remaining items do not affect safety. We help you plan the submittal so the CO arrives on schedule.
What information do you need to prepare change of use plans?
The address, a description of the current and proposed use, photos, existing floor plans or measurements, the approximate number of people expected, and any comments from the building or zoning department. A copy of the existing Certificate of Occupancy, if available, is very helpful.
Get your free change of use & co plans proposal
Tell us where the project is and what you need. Attach any drawings, photos or plan-check comments. A licensed engineer reviews every request.
- Upload your filesPlans, sketches, photos or comments
- Get a fixed-fee proposalUsually the same day
- Receive stamped drawingsSealed by a PE licensed in your state