Tenant improvement projects vary wildly in duration—a small office refresh might wrap in 8 weeks, while a full-scale retail conversion could take 6 months or longer. The timeline depends heavily on scope, permitting speed, and contractor availability. Here's what you actually need to know to plan realistically.
The Basic Timeline Breakdown
Most tenant improvements follow a predictable sequence, though overlaps can compress the schedule. Expect these phases:
- Pre-construction (2–6 weeks): Design finalization, permitting, and contractor selection
- Permitting & approvals (2–8 weeks): Building department review; longer in dense urban areas
- Construction (4–16 weeks): Actual build-out, depending on complexity
- Punch list & final inspections (1–3 weeks): Fix defects, pass final sign-off
Small office updates typically run 8–12 weeks total. Medium builds (retail, light medical, small restaurants) sit at 12–20 weeks. Large, complex projects (full-floor offices, hospitality, food service with gas/hood systems) routinely hit 5–8 months.
Permitting: The Hidden Timeline Killer
Permitting is where most projects slip. A straightforward office refresh with cosmetic changes might clear in 3 weeks. But if your tenant improvement involves electrical rewiring, plumbing, structural changes, or system upgrades, expect 4–8 weeks minimum—sometimes 12+ weeks in jurisdictions with backlogged building departments.
Plan for at least one revision cycle with the city. Most plans come back with comments requiring 1–2 weeks of corrections. Expedited permitting exists in some markets (costing 15–25% more), but it's not universally available.
Pro tip: Submit designs 2–3 weeks before your contractor is ready to start. Don't let permitting delays stall construction prep.
Design & Planning Phase
Before shovels hit the ground, allocate 2–6 weeks for design development and contractor selection. If you're using an architect or designer, add another 1–2 weeks for revisions. If you already have a finalized design, this phase shrinks to 2–3 weeks.
During this window, your contractor should be pricing the work, identifying material lead times, and flagging any unforeseen challenges (hidden asbestos, structural issues, existing utility conflicts). This is when honest conversations about budget and timeline happen—not halfway through construction.
Construction Duration: What Affects Speed
The actual build varies dramatically by project type:
Light refresh or office reconfiguration: 6–10 weeks. New finishes, partition walls, paint, flooring.
Retail or restaurant base build: 10–16 weeks. Includes MEP rough-in (mechanical, electrical, plumbing), drywall, finishes, and equipment installation.
Medical or lab space: 14–20+ weeks. Specialized finishes, strict code compliance, and equipment coordination add time.
Hospitality or food service: 12–18 weeks. Complex mechanical systems, kitchen equipment, and health department approvals extend schedules.
Material delays now regularly add 2–4 weeks to any project. Supply chains remain unpredictable for specialty finishes, HVAC components, and kitchen equipment. Confirm long-lead items (custom millwork, specialty lighting, equipment) before signing your contract.
Managing Surprises
Hidden problems emerge in roughly 60% of tenant improvements. Budget 1–3 weeks for discovery and correction. Common culprits:
- Obsolete or hazardous materials (asbestos, lead paint, old electrical)
- Structural issues or code-noncompliance in existing space
- Undersized utilities that need upgrades
- Roof or envelope leaks discovered during demolition
Contractors experienced with your building type and local codes catch these faster. This is where hiring through a trusted comparison platform like Mercoly—where you can vet multiple providers and see their experience—saves time and money.
How to Compress Your Timeline
If you're working against a deadline:
- Get designs 100% locked before permitting submittal
- Use expedited permitting if available (budget extra 10–20%)
- Pre-order long-lead materials immediately upon contract signing
- Hire a general contractor with availability—not the one starting in 6 months
- Build a 2-week contingency buffer into your critical deadline
Realistic compression typically cuts 3–4 weeks off a standard schedule, not months.
Frequently Asked Questions
Q: Can I occupy the space before the punch list is complete? Most lease agreements and building codes prohibit occupancy until the certificate of occupancy is issued. Partial occupancy during punch list work is occasionally negotiated but creates safety and liability issues—avoid it.
Q: What's the typical cost impact if the project runs over schedule? Extended general contractor overhead, extended labor, and indirect costs typically run $500–$2,000 per day depending on project scale and crew size. Even a 2-week delay adds meaningful expense.
Q: Should I hire a project manager separate from the general contractor? For projects exceeding $500K or involving multiple complex trades, a dedicated owner's representative or project manager (costing 3–5% of construction budget) often pays for itself through coordinated scheduling and issue resolution.
Get quotes from vetted tenant improvement contractors today—compare timelines, pricing, and expertise to find the right partner for your project.