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How many slabs for a 50-, 100-, or 200-unit building?

There's no single slabs-per-unit multiplier that holds across a 50-, 100-, and 200-unit job — what scales with building size is the unit mix, not the door count, so the honest answer is a method, not a lookup table. A real 108-unit job across 3 unit types (Ridgeline Flats) nested to 132 slabs at 81.6% yield with a 0.133″ kerf. A 50-unit building built from a similar unit-mix ratio would trend toward comparable per-unit density; a 200-unit building with a different split of studios, one-beds, and larger units won't simply be that number doubled, because slab count follows how each unit type's pieces actually pack, not total square footage. What follows is the method that produces a real count at any scale, not a rounded multiplier.

What scales with building size, and what doesn't

Two things stay roughly fixed regardless of how many units a building has: kerf and edge offset are per-cut clearances, not per-building ones, so they don't compound as a job gets bigger (see kerf and edge offset). And a building built from the same unit-mix ratio as a smaller job — the same proportion of studios to one-beds to larger units — tends to hold a similar yield percentage, because yield is driven by how those unit types' pieces pack together, not by how many times the mix repeats.

What does scale is the slab count itself, in rough proportion to how many times the unit mix repeats, and the number of ≤6-slab batches a crew has to work through (see the six-slab batch). A 200-unit building with a different unit mix than a 100-unit reference job — more larger units, an added unit type, a different island count — won't land on double that job's slab count, because the piece geometry driving the count changed along with the size. There's no published per-size total here that would hold across buildings with different mixes; the method below is what produces an honest number for a specific building.

132 slabsRidgeline Flats demo: 108 units, 3 unit types
81.6% yieldsame nest, 0.133″ kerf
≤6-slab batcheshow the shop that built this actually cuts

The method, walked through on a real 108-unit job

The Ridgeline Flats demo job's 132 slabs at 81.6% yield didn't come from a formula applied to 108 doors. It came from this sequence, which holds at any building size:

  1. Break the building into unit types, not a door count. Ridgeline Flats is 108 units across 3 unit types — the unit type, not the total, is what actually has a countertop shape to nest.
  2. Nest one unit type's real piece geometry — the actual DXF outlines for that unit's islands, runs, and splash strips — to get a slab count and yield for that type alone. The free web estimator does this for up to 3 unit types with no upload.
  3. Repeat per unit type, then combine — each type contributes its own slab count at its own yield; see multifamily countertop estimating for how shops batch a job by unit type rather than sizing it from one area figure.
  4. Batch the cutting in ≤6-slab groups per unit type, so a crew works through a layout it can actually execute on the saw, rather than a scattered count across the whole job.
  5. Validate the assembled layout before it's a number you'd bid — an independent check for overlaps, off-slab placement, and kerf-clearance violations, the same gate every StoneNest nest passes before export.

Run that sequence on a 50-unit or 200-unit building with its own real unit mix, and it produces that building's own honest count — not Ridgeline Flats scaled up or down.

Owner-operator note: the shops that run this without a mix-aware method usually protect themselves by rounding up "just in case" as the building gets bigger. The more common failure isn't running short — it's finishing a job with a couple of extra slabs that just sit in the rack, for years, because they were bought for one specific job in one specific material. A bigger building means more of that risk, not less, which is exactly what a per-unit-type count is for.

FAQ

Does slab count scale linearly with unit count?

Not reliably. Slab count follows the unit mix — how many of each unit type, and how that type's pieces pack — not the total door count. A building with the same unit-mix ratio as a smaller reference job will trend toward similar per-unit density, but a different mix at a larger size won't be a simple multiple.

How many slabs did a real 108-unit building actually need?

StoneNest's published Ridgeline Flats demo job — 108 units across 3 unit types — nested to 132 slabs at 81.6% yield with a 0.133 inch kerf. That number came from nesting the real per-unit-type piece geometry, not from a square-footage formula.

What actually changes between a 50-unit and a 200-unit building?

Total slab count scales with how many times the unit mix repeats, and the number of six-slab cutting batches goes up. Kerf and edge-offset clearances stay the same per cut regardless of building size, and yield percentage tends to hold steady if the unit-mix ratio is similar — it moves when the mix itself changes.

What's the fastest way to size my own building instead of guessing from a reference job?

Run your own unit types through the free web estimator for a per-mix slab count and yield on up to 3 unit types, then nest the full building — every unit type, real DXFs, a validated and exportable count — on the desktop app's 7-day free trial.

Related guides

Slab count

How Many Slabs Do You Need?

Why slab count isn't a flat square-footage ratio, and what actually drives the number on a real multifamily job.

 Multifamily

Multifamily Countertop Estimating

Why multifamily bids nest by unit type and quantity, not by multiplying one kitchen's square footage by the door count.

 Production workflow

The 6-Slab Batch

Why production shops nest and cut a few slabs at a time, not the whole job at once.

See what your own job nests to

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