Every operator asks this question. Most of them make the decision before they have the numbers to make it correctly.
When an operator is evaluating a new location, the decision usually comes down to two options: build from the ground up (build-to-suit, or BTS) or take over an existing space and renovate it to fit (second-generation, or second-gen). Both options have advocates. Both have honest trade-offs.
The problem is that most operators compare an optimistic second-gen estimate against a realistic BTS budget. They assume the existing building is "mostly done" — that they're paying for finishes and equipment, not structural work. They're often wrong.
After 24 years and 500+ projects, I've seen both sides of this comparison more times than I can count. Here's how to run it correctly.
What a build-to-suit actually costs
I covered the full BTS budget breakdown in a prior article ("What a $5M build actually costs"), so I'll give the summary here:
A typical $4-6M standalone commercial build-to-suit breaks down roughly like this:
| Category | % of total | $ on a $5M build |
|---|---|---|
| Site and civil | 8-12% | $400-600K |
| Structure and shell | 25-30% | $1.25-1.5M |
| MEP | 25-30% | $1.25-1.5M |
| Interior finishes | 15-20% | $750K-1M |
| FFE | 5-8% | $250-400K |
| Soft costs | 8-12% | $400-600K |
| Contingency | 8-10% | $400-500K |
The honest BTS advantage: You get exactly what you need, built to current code, with a full manufacturer's warranty on every system. Your HVAC units are new. Your electrical panels are new. Your plumbing is new. Nothing is inherited from a prior tenant whose use patterns or deferred maintenance decisions you don't know.
The honest BTS disadvantage: Timeline and predictability. A ground-up commercial build takes 12-18 months from site selection to certificate of occupancy in most markets. You carry the site cost, the construction loan interest, and the opportunity cost of that time with no revenue. And a BTS is exposed to all the site and design risk I covered in the BTS mistakes article.
What second-generation space actually costs
This is where most operators' assumptions break down. Second-gen space is not free renovation. The cost structure depends heavily on three things: the prior tenant's use, the building's age, and how closely the prior use matches your intended use.
Case 1: High conversion match (prior use similar to yours)
A QSR operator taking over a prior QSR space has the highest chance of a low-cost second-gen renovation. The MEP infrastructure is designed for food service. The grease trap exists. The hood rough-in may be usable. The walk-in refrigeration may be salvageable.
Realistic cost range: $75-150 per square foot for a high-match conversion. On a 3,000 square foot space, that's $225,000-$450,000. Looks cheap against a $5M BTS.
What that range assumes: The existing MEP is in good condition and compatible with your equipment. The building envelope (roof, HVAC, electrical panels) has remaining useful life. The prior tenant's hood, grease trap, and ventilation are adequately sized for your operation.
What it doesn't assume: You'll often find — after a building inspection and MEP assessment — that the prior tenant's HVAC is 15 years old, the electrical panel doesn't have capacity for your equipment, and the grease trap is undersized for your volume. Each of those discoveries is a change to the cost estimate.
Case 2: Moderate conversion match (prior use different but same building type)
A fitness operator taking over a prior retail space, or a healthcare operator taking over a prior restaurant. Different mechanical requirements. Different plumbing configuration. Potentially different structural loading for equipment.
Realistic cost range: $125-225 per square foot. On a 4,000 square foot space: $500,000-$900,000. Still below BTS, but the gap is narrowing.
Key cost drivers in this scenario:
- MEP reconfiguration (biggest variable — can run $200-400K on a medium-sized space)
- ADA compliance upgrades (if the existing space is non-compliant, you inherit the obligation)
- Structural modifications for new equipment loads
- New permitting for change of use (some jurisdictions require full plan review for change-of-use projects, which adds time)
Case 3: Low conversion match (prior use substantially different)
A medical operator taking over a prior retail shell, or a QSR taking over former office space. Essentially, you're doing a ground-up interior build inside an existing envelope.
Realistic cost range: $175-300+ per square foot. On a 3,500 square foot space: $612,000-$1,050,000. You're now approaching BTS territory on total construction cost — while potentially inheriting a building with age-related issues a BTS wouldn't have.
At this point, the BTS comparison needs to be done honestly, because the second-gen "savings" may have evaporated.
The hidden costs of second-gen that don't appear in the first estimate
The first estimate you get for a second-gen renovation is almost always optimistic because it's based on a visual inspection of the space — not a detailed MEP assessment, not a structural engineering review, and not a deep dive into what the prior tenant left behind.
Four categories that consistently come in higher:
1. MEP remediation. Existing MEP systems that look functional may not be up to current code for your use, or may not be compatible with your equipment. A QSR's hood and exhaust system is specific — if it doesn't fit your cooking equipment layout, it's a cost to reconfigure. HVAC units that are at end of useful life are a capital cost you inherit.
2. ADA compliance. If the existing space doesn't meet current ADA requirements, a change-of-use permit typically triggers a compliance obligation. Budget for accessible restroom upgrades, accessible path of travel modifications, and signage — often $30-80K depending on the scope.
3. Hazardous materials. Buildings built before 1980 may contain asbestos-containing materials in floor tiles, ceiling tiles, pipe insulation, or exterior materials. Lead paint on interior surfaces. Discovering these mid-renovation is a cost and a schedule hit. A pre-construction hazardous materials survey costs $2,000-5,000 and is worth every dollar.
4. Landlord's TI allowance vs. actual TI cost. In leased second-gen space, the landlord often offers a tenant improvement (TI) allowance — a contribution toward renovation costs. The TI allowance is almost always below your actual cost. A $50/SF TI allowance sounds meaningful on a 3,500 square foot space ($175,000). Your actual TI cost may be $350,000. The gap is your cost.
The timeline comparison
BTS: 12-18 months from site control to CO in most markets. Includes design (3-4 months), permitting (2-4 months), and construction (6-12 months).
Second-gen renovation: 4-8 months from lease execution to CO in most markets. Includes design (4-6 weeks for TI drawings), permitting (4-12 weeks depending on jurisdiction and scope), and construction (8-20 weeks depending on scope).
The timeline advantage of second-gen is real — and for operators who need to open quickly, it's often the deciding factor. A location that opens 8 months earlier generates 8 months of revenue the BTS doesn't.
At $50,000/month in revenue on a QSR unit, 8 months of earlier opening is worth $400,000. That changes the math significantly.
How to run the comparison honestly
The decision isn't "BTS cost vs. second-gen estimate." It's "BTS total cost of ownership vs. second-gen total cost of ownership, adjusted for timeline."
Here's the framework I use:
Step 1: Get a real second-gen estimate — not a landlord's conceptual allowance, but a contractor's estimate from actual drawings or at minimum a detailed scope. Include MEP assessment.
Step 2: Identify the age and condition of the building envelope (roof, HVAC, electrical). Budget for remaining useful life — if the HVAC is 12 years old on a 15-year building, you're likely replacing it within the lease term.
Step 3: Price the timeline gap. How many months earlier does second-gen open vs. BTS? Multiply by your projected monthly revenue. This is the opportunity cost of the BTS path.
Step 4: Add contingency to both numbers. Second-gen renovations in older buildings carry 15% contingency, not 10%. Discovery risk is higher.
Step 5: Compare total costs including carrying costs (construction loan interest, site cost) for BTS.
That's the real comparison. Not the headline numbers — the fully-loaded numbers.
The wry observation I'll offer: the deals I've seen operators regret most weren't the expensive BTS projects — they were the cheap-looking second-gen deals where the building inspection wasn't done and the MEP remediation cost was a surprise at month three.
Running the BTS vs. second-gen comparison on an active site? We do this analysis as part of our preconstruction consulting. Getting the numbers right before you sign the lease or ground lease is the entire point.