Introduction
This case study is a hypothetical, illustrative example. The project, the numbers, and the people described below are fictional — constructed to demonstrate how tile estimating works on a realistic project from first measurement to final order. No real client, contractor, or property is involved.
Follow along with the Tile Calculator open in another tab: every calculation below is one you can replicate with your own dimensions. The complete guide covers the same formulas in general form.
The Project (Hypothetical Scenario)
Imagine a homeowner — let’s call her Maya — renovating a hall bathroom in a 1990s suburban house. The scope: re-tile the floor and the tub surround. The existing vinyl floor is coming up; the tub stays. Maya is a confident DIYer who has painted and done basic carpentry but never tiled. She decides to DIY the floor and hire a professional for the tub surround, a hybrid approach covered in the DIY vs pro guide.
Her material choices: 12 × 12 in (30 × 30 cm) porcelain for the floor in a straight layout, and 3 × 6 in subway ceramic for the tub surround. Both are forgiving, widely available formats.
Step 1: Measuring (What Maya Found)
Maya sketches the bathroom and measures twice. The room is 8 ft × 6 ft (2.44 × 1.83 m) — 48 ft² (4.46 m²) gross. Fixtures:
- Vanity: 2.5 × 2 ft = 5 ft²
- Toilet zone: 2.5 × 2.5 ft = 6.25 ft²
- Built-in tub (staying in place): 5 × 2.5 ft = 12.5 ft²
Because the tub and vanity are staying and she’s tiling around them (a simplification a pro might not choose, but reasonable for this hypothetical), her net floor area is 48 − 5 − 6.25 − 12.5 = 24.25 ft² (2.25 m²).
The tub surround: the tub is 5 ft long, and she’s tiling the wall above it 4 ft high on the long wall, plus the two 2.5-ft end walls at 4 ft high. That’s (5 × 4) + 2 × (2.5 × 4) = 20 + 20 = 40 ft² (3.72 m²) of wall.
Measuring technique for each surface type is detailed in the estimating guide.
Step 2: The Floor Calculation
Floor: 24.25 ft² net, 12 × 12 in tiles (1 ft² each), straight layout, simple rectangle → 10% waste.
- Base tiles: 24.25 ÷ 1 = 24.25 → 25 tiles
- With waste: 25 × 1.10 = 27.5 → 28 tiles
- Boxes (9 per box): 28 ÷ 9 = 3.1 → 4 boxes (36 tiles)
- Thinset (1/4-in notch, ~75 ft² per 50-lb bag): 24.25 ÷ 75 → 1 bag
- Grout (sanded, 1/8-in joints): one 10-lb box is plenty; she buys a 25-lb bag to have margin
- Backer board (3 × 5 ft sheets): 24.25 ÷ 15 = 1.6 → 2 sheets
Step 3: The Tub Surround Calculation
Walls: 40 ft², 3 × 6 in subway tile (0.125 ft² each), walls with a window cutout and plumbing penetrations → 15% waste.
- Base tiles: 40 ÷ 0.125 = 320 tiles
- With waste: 320 × 1.15 = 368 tiles
- Boxes (sold by ft² coverage for subway — 10 ft² per box): 40 × 1.15 = 46 ft² → 5 boxes (50 ft²)
- Thinset (V-notch for wall tile): 1 bag (walls use less than floors)
- Grout (unsanded, 1/16-in joints): 1 × 25-lb bag
- Waterproofing membrane: wall area ≈ 40 ft² → one gallon of painted-on membrane per manufacturer coverage
Note the waste decision: 15% rather than 10% because the surround has a window, a showerhead penetration, and a niche — every one of them a cut generator. The formula guide derives the waste logic.
Step 4: The Budget (Illustrative Figures)
Using typical retail ranges (not quotes), Maya’s hypothetical budget looks like this:
| Line item | DIY floor | Pro surround |
|---|---|---|
| Tile | $90–$180 (4 boxes porcelain) | $160–$320 (5 boxes subway) |
| Setting materials | $80–$140 | $100–$180 |
| Tools (saw rental + consumables) | $120–$200 | $0 |
| Labor | $0 | $400–$800 (40 ft² × $10–$20) |
| Subtotal | $290–$520 | $660–$1,300 |
Hypothetical project total: roughly $950–$1,820. The cost guide breaks down each line item for real projects.
Step 5: What Went Right (in This Hypothetical)
- One order, one dye lot. Maya ordered all tile at once — the floor porcelain and surround subway each from a single lot — avoiding the mismatch problem described in the common mistakes guide.
- Kept the spares. The leftover half-boxes went into the garage, labeled with SKU and lot — future-repair insurance.
- Hired the wet area. The tub surround’s waterproofing membrane and plumbing penetrations went to a pro, who flood-tested the membrane before tiling — the inspection step from the code compliance guide.
- Caulked the changes of plane. Tub-to-tile and corners got silicone, not grout — per the pro tips guide.
What This Hypothetical Teaches
The pattern generalizes: measure net area honestly, match waste to layout complexity, estimate each surface separately, order everything at once, and put professional skill where the stakes are highest (wet areas, waterproofing). Maya’s numbers are fictional, but the method is exactly what the Tile Calculator automates — and the project checklist sequences the work the same way.
Related Guides
- Tile Calculator Complete Guide — the estimating method used here.
- Cost Guide — budgeting your real project.
- DIY vs Pro — the hybrid approach illustrated above.
- Tiling Project Checklist — the step sequence in order.
- How to Estimate — measuring technique.
Frequently Asked Questions
Is this case study based on a real project?
No. It is explicitly a hypothetical, illustrative example constructed to demonstrate the estimating method. The person, property, measurements, and costs are fictional.
Can I follow the same steps for my bathroom?
Yes — the method (measure net area, estimate each surface separately, apply layout-appropriate waste, order in one lot) applies to any tile project. Substitute your own measurements into the Tile Calculator.
Why tile around the fixtures instead of under them?
In this hypothetical, the tub and vanity were staying in place and couldn’t be moved — a common real-world constraint. Where fixtures can be removed, tiling the full floor underneath is the better practice; it avoids awkward cuts and future-proofs fixture swaps.
Run Your Own Numbers
Hypothetical Maya’s project is done — yours is waiting. Measure your space, work through the project checklist, and run the numbers through the Tile Calculator. The method is proven; only the measurements change.
Disclaimer: This case study is a hypothetical, illustrative example only — all people, properties, measurements, and costs are fictional. It is intended to demonstrate estimating methodology, not to represent any real project outcome. Calculator results are planning estimates; verify quantities with your supplier and consult a qualified professional before ordering or installing.
