For a typical 50,000–100,000 square-foot medical office building (MOB), plan for 18–30 months from initial concept to opening, with the biggest variables being delivery method, Authority Having Jurisdiction (AHJ) reviews, and specialty scope such as imaging or an ambulatory surgery center (ASC).

Why it matters

Time drives return on invested capital. At a 5% cost of capital, each month of delay on a $50 million project translates to roughly $208,000 in carrying cost before a single patient is seen—capital that could otherwise support clinical growth or workforce initiatives. In today’s environment of higher borrowing costs and competitive ambulatory expansion, compressing the schedule without compromising quality directly improves ROI and speeds access to care.

Market dynamics also favor timely delivery. In fast-growing regions such as Nashville and Middle Tennessee, physician alignment, outpatient market share, and site control move quickly; a slow real estate timeline can force program compromises or lost opportunities. The goal is realism—anchoring milestones to evidence-based benchmarks—so executives can align clinical, capital, and operational decisions with confidence.

How it works

The end-to-end MOB timeline typically includes: strategic alignment and programming; site control and entitlements; design; permitting and AHJ plan review; construction; equipment, commissioning, and occupancy. While organizations vary, the full path commonly totals 18–30 months, with design-bid-build on the longer end and integrated delivery on the shorter end. Design-build delivery has been shown to deliver projects an average of 36% faster than design-bid-build, often translating to several months saved on an MOB of this size and complexity (Design-Build Institute of America Best Practices Study
).

Two levers materially affect the schedule. First, early decisions that enable a Guaranteed Maximum Price (GMP)—the contractor’s capped cost commitment—allow procurement of long-lead materials sooner, pulling risk out of the critical path. Second, using prefabrication and modular strategies (e.g., MEP racks, exam room headwalls) can cut on-site durations; owners in healthcare have reported up to 20% faster schedules from these methods (Dodge Construction Network Modular & Prefabrication Toolkit). These efficiencies stack with design-build to provide the most reliable way to convert months into weeks.

Key considerations

Regulatory compliance sets the floor for scope and review timelines. Outpatient facilities must adhere to the Guidelines for Design and Construction, which drive space, infrastructure, and life safety requirements that AHJs reference during plan review and inspections (FGI Guidelines). If your program includes an ASC, imaging (e.g., MRI), or certain other services, additional approvals may apply; in some states, a Certificate of Need (CON) is still required for specific services even when the medical office itself is not. For example, Tennessee maintains CON oversight for select facility types and services through the Health Facilities Commission (Tennessee CON).

Scope drives duration. Ground-up projects with structured parking, high-acuity services, or complex site work take longer than a clinic build-out in existing shell space. Long-lead elements such as imaging equipment, emergency generators, air handlers, and switchgear can become schedule drivers if not procured early. Finally, align occupancy strategy with AHJ sequencing: plan review, life-safety inspections, and phased occupancy approvals vary by jurisdiction and must be built into the critical path. Define AHJ early, clarify submittal expectations, and sequence mock-ups and commissioning to avoid late-stage surprises.

Actionable takeaway

Use an evidence-backed master schedule at day one, then pull time out with integrated delivery. Choose design-build to capitalize on its proven speed advantage; set an early GMP to lock in procurement; and standardize exam modules to enable prefabrication. Validate FGI-driven room and infrastructure requirements up front, meet early with the AHJ to confirm plan review and inspection paths, and establish a risk register for long-lead items. For a structured approach to scope, delivery, and approvals—as outlined in our healthcare real estate services—review the milestones in our healthcare real estate services, see how schedule governance fits within our advisory approach, or request a working session to test your timeline assumptions.

FAQs

What’s the single biggest factor that compresses or extends an MOB schedule?

Delivery method is usually the largest controllable driver; design-build projects are statistically faster than design-bid-build, and pairing design-build with targeted prefabrication often removes additional months by pulling procurement and fabrication off the critical path.

How do FGI Guidelines affect the timeline?

FGI Guidelines define minimum space, safety, and systems requirements for outpatient care areas, which AHJs use during plan review and inspection; aligning your program and drawings with FGI early reduces back-and-forth with reviewers and avoids rework late in construction.

Do we need a Certificate of Need for a medical office building?

The medical office building itself often does not require a CON, but specific services inside it may; for example, an ASC or certain imaging modalities may trigger CON in states like Tennessee, so verify requirements during programming to prevent approval delays.

How much time can prefabrication realistically save?

Owners and contractors report up to 20% schedule reductions from prefabrication and modular strategies in appropriate scopes, especially when standardized exam rooms and MEP distribution allow off-site assembly and just-in-time installation.

When should we set a GMP?

Set a GMP as soon as scope has sufficient definition to price meaningfully—often at the end of design development in a progressive design-build approach—so critical materials and equipment can be procured earlier, reducing exposure to supply-chain and escalation risk.

Bremner Real Estate partners with health systems to align real estate strategy with clinical performance and capital efficiency.