I’ve watched perfect planning fail over a simple mistake.

Allocating drafting teams at 100% capacity, every hour assigned, every project slotted.

Then an unplanned redline comes in.

Without reserve capacity, you pull from one project to help another. Both slip. Clients get frustrated. The team works overtime, quality drops, and the spiral begins.

I learned this the hard way. Now, I always build in a 10% buffer. Which means we always have people in reserve for the unexpected.

The Three Red Flags

While every project is different, as work progresses there are some “red flags” that hint at a project about to become a resource-eater:

• Unclear scope or drawings. Weak foundations multiply revisions.
• Unresolved RFIs. Questions left open become problems later.
• Frequent mid-draft changes. A shaky start predicts a rough finish.

When I spot these, I expand the buffer before trouble hits.

The Inverse Scaling Rule

Here’s what I’ve learned over the years: smaller projects need bigger buffers.

• Under 50 hours? I reserve at least 16 hours,  about 32% of the original project (specially for custom residential work)
• Between 50 to 500: 10% reserved capacity is a good rule of thumb
• Over 500 hours? 10% might be overkill.

The math seems backward, but small projects have less room for error. One mistake eats a larger share of time.

Research on capacity planning backs this up: once teams pass 80% utilization, deadlines slip and quality drops.

When You Skip the Buffer

We once rushed a submittal and skipped part of our quality check, one of those “just this once.” Situations.

That shortcut exploded into client revisions. They weren’t just unhappy about the errors; they were frustrated at having to review what should’ve been clean work.

We pulled people off other projects to fix it. Those slipped too.

The hours we tried to save turned into a long line of scheduling chaos.

Studies show poor quality costs 15%–35% of total business costs. We experienced it firsthand.

The Early Warning System

Reserve capacity only works if you can see problems coming.

I track not just progress, but quality of progress.

I ask where each project stands, verify against the schedule, and look for gaps between plan and reality.

That visibility catches quiet drifts before they become failures.

Quality issues get exponentially more expensive the longer they go unnoticed.

The 10% buffer gives me space to act, not just watch.

The Bottom Line

Scheduling at 100% feels efficient. It’s not.

It’s a guarantee that something will break.

The buffer is the plan. Everything else is just hoping for perfect conditions that never come.

Nicolae Cespedes

Director of Operations