The biggest planning mistakes on commercial projects are predictable: setting a budget before the program is defined, picking a site without testing it, locking the design before the contractor sees it, underestimating permitting timelines, and treating the schedule as a wish rather than a constraint. Each one is avoidable. Each one shows up in real projects every year, often in the same week the owner thought construction would start.

Here are the mistakes we see most often, why they happen, and what to do instead.

Mistake 1: Setting a budget before the program is defined

A board approves “a new 40,000 square foot facility for around $8 million” before anyone has confirmed what the building actually needs to do. Then the program lands: lab space with specialty exhaust, a backup generator, an MRI-rated slab, or a clean room. The number was never realistic, and now every conversation is a negotiation about what to cut.

The fix: Define the program first. List operations, headcount, equipment, finishes, and code drivers. Then build the budget from that program, including soft costs (design, permits, FF&E, contingency), not just hard construction. A 10 to 15 percent owner contingency on a ground-up commercial build is not pessimism, it is planning.

Mistake 2: Choosing a site before it has been vetted

The site looks great on a drive-by. The price is right. The seller wants to close in 30 days. Six months later you find out the soils need over-excavation, the sewer tap is on the wrong side of a state road, or the zoning requires a special use permit with a six month hearing cycle.

The fix: Before closing, run a site evaluation: geotechnical borings, a utility availability check with the local providers, a stormwater and floodplain review, and a zoning confirmation in writing. This is exactly what overall project and site evaluation under a design-build approach is meant to catch.

Mistake 3: Designing in a vacuum, then asking for a price

The architect produces a beautiful 100 percent set. The owner sends it to three contractors. All three come back 20 to 35 percent over budget. Now you redesign, lose three months, and pay the design team twice.

The fix: Bring the builder in during design. A contractor who is pricing as the drawings develop will flag the $90 per square foot curtain wall before it is specified, suggest a tilt-up panel instead of a CMU back-up, and tell you the long-lead switchgear needs to be ordered before foundations are poured. That is the core argument for design-build on institutional projects, and it applies just as much to industrial, retail, and healthcare work.

Mistake 4: Treating permitting as an afterthought

Owners often assume permits take “a few weeks.” Across North Carolina, Virginia, and Tennessee, a commercial plan review can run 8 to 16 weeks, longer if the project triggers state-level review (healthcare, schools, fuel storage). Add stormwater, driveway permits, fire marshal sign-off, and health department approval for food service or medical use, and you are looking at a real critical-path item.

The fix: Map every required approval at the start. Build the permit sequence into the master schedule. Submit early, respond to comments fast, and never assume an inspector’s interpretation matches yours. Get it in writing.

Mistake 5: Confusing low bid with best value

The cheapest number wins the contract. Then come the change orders: items that were “clarifications,” subcontractors who walked, schedule slippage that pushes occupancy into the next fiscal year. The savings vanish before drywall goes up.

The fix: Evaluate contractors on track record, financial stability, safety record, and the quality of their subcontractor relationships, not just the bid number. A complete, qualified bid from a builder you trust is almost always cheaper than a low number you have to renegotiate.

Mistake 6: No single point of accountability

When the architect, contractor, civil engineer, and owner’s rep all report to different people with different contracts, decisions stall. Someone has to own the outcome.

The fix: Either appoint a strong owner’s representative or use a delivery model that consolidates responsibility. Under design-build, one contract covers design and construction, which is why timelines compress and finger-pointing drops.

A better way to plan

Most of these mistakes share a root cause: starting construction conversations too late and ending them too early. Pull the builder in during programming, vet the site before you buy it, and treat the schedule and budget as living documents tied to real decisions.

If you are sizing up a project and want a second set of eyes before the budget hardens, reach out to the Hayco team. We have built across healthcare, industrial, aviation, retail, and institutional work, and most of what we offer at the planning stage is hard-won pattern recognition.