Build a job: how to calculate countertop square footage, seams and support
To calculate countertop square footage the way a shop does a take-off, run length times depth in inches and divide by 144 — then add the island, any waterfall panel, the backsplash and the strips that build up a mitered or laminated edge, and divide by the slab's planning yield to give slab-equivalents. Every answer here is worked from the measured run, depth and island, and lands on the drawing. The stamp along the top carries the take-off, the seams, the support call and whose day it is; the numbered notes below the views are the callouts they belong to. Change one control and watch the sheet redraw; hover any detail on it — the sink, a seam, the overhang, the waterfall — and the panel on the right tells you what it is, who does it and which machines it takes.
- 1. Drop-in: the bowl is lowered in from above and its rim rests on the surface, covering the cut edge. Imperfections disappear under the rim.
- 2. No seams — the run fits one slab, and a compact L can leave the shop in one piece.
- 3. Inside the rule of thumb — commonly run without added support. The shop's own limit, not a building code.
- Slab handling & lifting Move full slabs, truck to saw. every slab move this job makes — truck, yard, saw, bench, truck again.
- Digital templating device Capture a kitchen's exact geometry into a digital file. how most custom kitchens start — the field file the whole ticket is cut from.
- Slab imaging & digital layout · a route Photographs and lays out real slabs on screen. shops that image every slab do it for yield and defect-dodging.
- Bridge saw Break raw slabs into rough tops and straight cuts. the usual first cuts.
- Sawjet · a route Straight and curved cuts on one machine. one machine that can take the blade cuts plus your openings and 45s — the route in shops that run one.
- CNC waterjet · a route Cutouts, curves, and inlays a saw can't reach. openings and curves without blade stress — a common route for the cutouts, if the shop runs one.
- CNC router / workcenter Edges, holes, cutouts, and drainboard grooves. the sink opening and faucet bores; the cooktop opening; machine-profiles and polishes your eased edge.
- Edge / line polisher Polishes long straight countertop edges. your long straight polished edges run the line.
- Hand & wet-finishing tools Finishes what the big machines start. what the machines start, the bench and the install crew finish.
- Water reclaim & slurry management Catches wet-cutting water, drops out solids, recycles it. shop infrastructure — every wet machine above drains into it.
Calibrating & surfacing line — not this job: slabs arrive calibrated. You meet that line in slab plants, not fab shops.
Worked examples — four of these jobs, read out in full
Builder-grade kitchen
The order. quartz, 3cm, eased edge, drop-in sink, cooktop, 6 in overhang, short backsplash, 96 in run.
Take-off. About 54 sq ft, about 2 slab-equivalents.
Seams. No seams — the run fits one slab, and a compact L can leave the shop in one piece.
Support. Inside the rule of thumb — commonly run without added support. The shop's own limit, not a building code.
Whose day. Routine work — Helper-assisted, fabricator-owned — the helper carries it, any fabricator finishes it.
Machines invoked. Slab handling & lifting · Digital templating device · Bridge saw · CNC router / workcenter · Edge / line polisher · Hand & wet-finishing tools · Water reclaim & slurry management.
Showpiece island
The order. marble, 3cm, mitered edge, undermount sink, waterfall end, 14 in overhang, full backsplash, 150 in run.
Take-off. About 108 sq ft, about 4 slab-equivalents. Vein matching uses more slab.
Seams. At the inside corner — the usual split for transport and yield, though not a law. A planning seam at about 83 in — the run runs past the reference slab, subject to stock and layout. Its location is kept clear of the cutouts.
Support. Past the rule of thumb — needs support under the span: concealed steel, brackets or corbels, sized and anchored by the shop.
Whose day. A lead's day — The shop puts its best on this ticket. a waterfall end is showpiece work; a mitered edge in marble is unforgiving.
Machines invoked. Slab handling & lifting · Digital templating device · Slab imaging & digital layout · Bridge saw · CNC router / workcenter · Hand & wet-finishing tools · Seam setter · Water reclaim & slurry management.
A 2cm laminated starter
The order. granite, 2cm, laminated edge, drop-in sink, cooktop, 8 in overhang, short backsplash, 120 in run.
Take-off. About 64 sq ft, about 2 slab-equivalents.
Seams. At the inside corner — the usual split for transport and yield, though not a law.
Support. Past the rule of thumb — needs support under the span: concealed steel, brackets or corbels, sized and anchored by the shop.
Whose day. A fabricator's day — Bench skill decides this one. a seam to close on site; concealed support fitted to the shop's detail.
Machines invoked. Slab handling & lifting · Digital templating device · Bridge saw · CNC router / workcenter · Hand & wet-finishing tools · Seam setter · Water reclaim & slurry management.
A porcelain penthouse
The order. porcelain, 2cm, mitered edge, undermount sink, cooktop, waterfall end, 10 in overhang, full backsplash, 132 in run.
Take-off. About 101 sq ft, about 3 slab-equivalents.
Seams. At the inside corner — the usual split for transport and yield, though not a law. A planning seam at about 73 in — the run runs past the reference slab, subject to stock and layout. Its location is kept clear of the cutouts.
Support. Past the rule of thumb — needs support under the span: concealed steel, brackets or corbels, sized and anchored by the shop.
Whose day. A lead's day — The shop puts its best on this ticket. a waterfall end is showpiece work; a mitered edge in porcelain is unforgiving.
Machines invoked. Slab handling & lifting · Digital templating device · Bridge saw · CNC router / workcenter · Hand & wet-finishing tools · Seam setter · Water reclaim & slurry management.