Converting a second-generation retail box into a clinic is a change of occupancy, not a cosmetic refresh. Expect six to twelve months from lease signature to first patient, and expect the money to go where you cannot see it: HVAC zoning, electrical service, under-slab plumbing, and shielded walls. The storefront and the paint are the cheap part.
Here is the sequence that actually works, in the order the decisions have to be made.
Step 1: Vet the box before you sign the lease
Walk the space with your contractor and a mechanical engineer before the LOI turns into a lease. You are looking for a short list of deal-breakers:
- Electrical service. A 6,000 square foot clothing store often runs on a 200 amp panel. A clinic with imaging, sterilizers, a dozen HVAC zones, and a full IT closet frequently needs 600 to 800 amps. A new service from the utility can add three to five months on its own.
- Roof structure. Retail typically has one or two rooftop units. You may need six or more. Somebody has to confirm the joists can carry the added curbs and weight.
- Under-slab plumbing. Every exam room needs a hand sink. If the existing sanitary line runs along one wall only, you are saw-cutting and re-trenching most of the slab.
- Column spacing and ceiling height. Columns at odd intervals wreck an exam room grid. Below about 12 feet deck height, ductwork and sound-rated partitions get tight.
- Sprinkler coverage. Open-plan head spacing rarely works once you build 20 rooms.
A few thousand dollars of feasibility work here is the cheapest money in the project. It has killed more bad deals for our clients than any other step.
Step 2: Confirm zoning, parking, and the landlord’s use restrictions
Medical office usually parks at a higher ratio than general retail, so a center that is already tight on spaces can fail the count even though the suite is empty. Some jurisdictions permit medical office by right in a commercial district; others require a special use permit with a public hearing, which adds 60 to 120 days. Read the lease for exclusives and prohibited uses too. Anchor tenants and existing medical tenants sometimes hold a restriction that quietly forbids your use.
While you are in the lease, look hard at the tenant improvement allowance and what it is allowed to cover. Landlords often write the allowance to exclude the exact scope a clinic needs, including service upgrades, rooftop units, and anything below the slab. An allowance that reads generously at $60 per square foot can shrink to almost nothing once those carve-outs apply, and by then you have signed.
Step 3: Settle the occupancy classification in writing
Retail is Group M. Most clinics and urgent cares become Group B. The expensive fork in the road is whether your facility qualifies as an ambulatory care facility, which generally applies when four or more patients are rendered incapable of self-preservation, typically through sedation, at the same time. That classification pulls in smoke compartmentation, sprinklers throughout, and standby power.
An urgent care that stitches lacerations and reads X-rays usually stays plain Group B. A center doing procedural sedation does not. Get the code official’s read during schematic design, in writing, because the difference is hundreds of thousands of dollars in scope. The change from M to B also triggers egress recalculation, accessibility upgrades along the path of travel, and energy code compliance on all new systems. Our overview of permits and code compliance in North Carolina covers how those reviews stack.
Step 4: Lay out for clinical flow, not for square footage
Design the plan around how patients and staff move, then let the square footage fall where it falls. Exam rooms usually land in the 100 to 120 square foot range, each with a hand sink and a clear approach to the table on the provider’s side. Put a staff corridor behind the exam rooms so providers are not walking the patient hallway all day. Keep imaging close to triage, because an ankle injury should not have to travel the length of the suite.
Wherever a conversation has to stay private, run partitions to the deck with insulation and offset the outlets. HIPAA lives in the wall assembly, not in a sign at the front desk.
Step 5: Size the MEP for a clinic
This is where retail conversions go over budget. Ventilation rates, exhaust, and pressure relationships in clinical areas follow ASHRAE 170, which means dedicated exhaust for soiled utility and lab, and negative pressure where you triage respiratory patients. Plumbing means hand sinks everywhere, a properly sized water heater, backflow prevention, and eyewash at the lab. Imaging means a physicist’s shielding report that dictates lead-lined gypsum, leaded glass, and a leaded door. If you are doing procedures, medical gas piping has to be installed and certified by a qualified party. Our note on healthcare planning, code, and infection control goes deeper on the infection control side.
Step 6: Bring the whole path of travel into ADA compliance
Alterations obligate you to make the path of travel to the altered area accessible, up to a disproportionate cost threshold. In practice that means accessible parking counts and striping, curb ramps, entry thresholds, a 36 inch section of reception counter, restroom clearances, and maneuvering room at doors. Fixing it in design costs almost nothing. Fixing it after the fire marshal’s walkthrough costs a month.
Step 7: Permit, build, and sequence the inspections correctly
Building permit and fire review run first. Radiation equipment registration with the state, CLIA certification for the lab, and any facility licensure run on their own clocks and typically require the space to be substantially complete. Order matters: air and water balance report, then medical gas certification if applicable, then final building inspections and certificate of occupancy, then the regulatory inspections that need an occupied, functioning space.
If the rest of the shopping center is open while you build, negotiate work hours, dust partitions, and fire alarm isolation up front. We wrote separately about upfitting without disrupting surrounding operations.
What it costs, in round numbers
Nobody can price your box from a blog post, but you should walk into the first meeting with a range in your head. A straightforward urgent care conversion in the Southeast, in a box that already has decent bones, generally runs in the low to mid hundreds of dollars per square foot for construction alone. Imaging suites, medical gas, procedural sedation scope, or a full utility service upgrade push it higher fast. Medical equipment, furniture, IT, and signage sit on top of that number, not inside it.
Two line items surprise owners more than any others. The first is the electrical service upgrade, which can run well into six figures once you add the utility’s own charges and the transformer lead time. The second is slab work, because trenching for sanitary lines is loud, slow, and impossible to value-engineer away after the layout is locked. Budget both honestly at the feasibility stage rather than discovering them in bid week. Our breakdown of what drives commercial construction costs up covers the pattern more broadly.
What a realistic schedule looks like
Feasibility and lease negotiation: four to eight weeks. Design and engineering: eight to fourteen weeks. Permitting: four to twelve weeks depending on the jurisdiction. Construction: sixteen to twenty-six weeks for a typical urgent care. Commissioning and licensure: three to six weeks. Long-lead switchgear or rooftop units can stretch any of it.
If you are evaluating a specific box in the Carolinas, Virginia, or Tennessee, Hayco Construction can walk the space with you and put real numbers against it before you commit to a lease. That conversation is usually the difference between a clinic that opens on schedule and one that stalls at the utility transformer.