Floor tile calculator

Every line shows the quantity to buy and how StudSheet got it: the spacing, the waste and the package size, so you can check it before the supply house or the quote.

In Canada (2.44 m × 1.52 m bathroom)

Set to Canada, the Sheet works the job out again for Ontario: metric sizes, bag sizes, the frost depth and the code notes. It doesn't just convert feet to meters. The first lines:

• 19 tiles (3.5 m²), Floor tile: A grid of whole tiles over 1.52 m × 1.68 m, plus one per offset row (762 mm × 1.52 m tub footprint left out) = 17, + 2 spares for breakage and future repairs. Buy from one lot number.
• 1 bag, Large-format tile mortar, 22.7 kg: 2.6 m² ÷ 3.7 m² per bag with a 13 × 13 mm square notch trowel, +20% for back-buttering.
• 3 sheets, Cement backer board 6 mm (3×5): 2.6 m² + 10% ÷ 1.4 m² per sheet.
• 1 bag, Modified thinset mortar, 22.7 kg: Backer board is set in thinset (6 mm square notch, ~7.4 m²/bag), not laid dry.
• ≈135 screws, Cement board screws 32 mm: A screw every 203 mm in each direction — about 45 per sheet.
• 1 roll, Alkali-resistant mesh tape 50 mm: Tape and thinset every backer seam.

1. Shut off the water, pull the toilet and stuff a rag in the drain. Remove the old floor down to the subfloor.
2. Screw down the subfloor and check flatness: ⅛″ in 10 ft for large tile.
3. Set ¼″ cement board in thinset, screws every 8″, gaps ⅛″; tape seams with alkali-resistant mesh and thinset.
4. Dry-lay from the doorway view: no slivers under half a tile at the door or along the tub. Keep the offset at ⅓ or less (long tile warps).
5. Mix thinset, let it slake 5–10 minutes, remix. Comb with the ½″ × ½″ square notch in straight lines; back-butter every tile; set leveling clips. Lift a tile now and then to check coverage.
6. Cut with the wet saw; notch around the flange with the grinder.
7. Wait 24 hours. Grout diagonally across the joints; clean the haze with a barely damp sponge.
8. Leave the wall and tub joint ungrouted and fill it with matching silicone.
9. Reset the toilet on a new wax ring, with the flange extender if the flange ends up below the tile. Seal the grout once it cures.

Must-have tools first, then the ones that help and the ones to rent for the day.

Mistakes that cost a callback or a second trip

• Grouting the change of plane: Grout at walls and the tub cracks as the house moves. That joint gets flexible silicone.
• Too small a trowel: Big tile over thin ridges leaves hollow spots that crack when stepped on. ½″ × ½″ square notch here, plus back-buttering.
• Forgetting the new floor height: The floor rises about 1″. Plan the toilet flange and the door threshold before you start.

What the calculator assumes

• Thinset per 50 lb bag: 80 sq ft (¼×¼), 60 (¼×⅜), 40 (½×½) — conservative values inside the Custom, MAPEI and LATICRETE data-sheet ranges. +20% for back-buttering large tile.
• Large-format = any edge ≥ 15″ (ANSI flatness rule: ⅛″ in 10 ft). Offset ≤ 33% when the offset side is over 18″.
• Grout: joint volume from tile size, joint width and tile thickness (3/8″), ≈ 0.065 lb per cu in, +15%.
• Sanded grout for joints ⅛″ and wider, unsanded below (manufacturers overlap at ⅛″).
• Deflection: L/360 for ceramic and porcelain, L/720 for natural stone (TCNA).
• A 30″ × 60″ tub along the short wall is left out.
• Tile count: whole pieces by rows × columns (a cut tile still uses a tile), +1 per offset row, +10% spares (13% for plank tile). Diagonal: area + 15%.
• Pre-1980s vinyl flooring and its adhesive can contain asbestos — test before removing.

The Sheet sets its code notes for the job's state or province. These are New Jersey's and Ontario's; the code reference has more. Always confirm with your building department.

• Permits: a job like this usually needs none, but towns set their own rules. Ask your building department if you're not sure.

What materials do I need to tile a bathroom floor?

For the worked example, a 8′ × 5′ bathroom, the Sheet counts 13 lines with waste included, starting with floor tile (19 tiles (38 sq ft)), large-format tile mortar, 50 lb (1 bag), cement backer board ¼″ (3×5) (3 sheets), modified thinset mortar, 50 lb (1 bag). Each line's math is in the table above. Put in your own sizes in the floor tile calculator and every line is counted again.

How long does it take to tile a bathroom floor, and can I do it myself?

About 11 to 16 hours for the worked example, in 9 steps. StudSheet stamps it DIY OK: you can do this.

What tools do I need to tile a bathroom floor?

30 in all. The must-haves start with notched trowel, margin trowel, ½″ drill + mixing paddle, 5-gal buckets (2), grout float, grout sponges + 2 buckets. On the Sheet you mark each one as owned, to buy or to rent.

Stuck while you tile a bathroom floor? Ask in the Floor tile group of the StudSheet community with this Sheet attached. Homeowners who've done it and verified pros answer, and anyone can read it.

• Tile for contractors: run this takeoff at your own prices, send the estimate, and get it signed and the deposit paid.
• Carpet a room (14′ × 12′ room): Tack strip, pad, seams and stretching — the full stretch-in install.
• Install vinyl plank flooring (14′ × 12′ floor): Click-together LVP: boxes, trim, transitions and the gaps that matter.
• Hardwood and laminate floors (14′ × 12′ floor): Install solid or engineered hardwood or laminate, or sand and refinish an old wood floor.
• Tile a kitchen backsplash (12′ of backsplash, 18″ tall): Tile, adhesive, grout, edge trim and outlet extenders for the wall between the counter and the cabinets, counted from the run and height.
• Tile a shower or tub surround (5′ tub surround, tiled to 7′): Backer board, waterproofing, tile, thinset and grout for a tub surround or a walk-in shower — every seam, corner and pipe sealed.
• Carpet stairs (13 steps, 3′ wide): Carpet, pad and tack strip cut step by step — waterfall or wrapped (Hollywood) — with the pile running down the stairs and the landing included.
• All 45 Sheets, across 16 trades.
• Code reference: frost depths, guard heights, stairs, retaining walls.