How to sell flooring by the box on Shopify
Short answer: let the customer enter their room's width and length, add the waste their laying pattern needs, and round up to whole boxes: boxes = round up (room area × (1 + waste) ÷ box coverage). The price is the boxes' coverage times your rate per m² or sq ft, plus underlay by area and edge trim by the room's perimeter. A Shopify Function charges it at checkout.
Why flooring is awkward on Shopify
Flooring is sold by the box, but customers know their room, not how many boxes it takes. Selling "1 box" with a quantity box leaves them to do the maths, add the waste and round up, and many get it wrong: too few boxes and the job stops, too many and they return them. A calculator on the product page turns the room size into boxes and a price, the way a shop counter does.
The box formula
area = width × length
area needed = area × (1 + waste %)
boxes = round up (area needed ÷ box coverage)
price = boxes × box coverage × rate per m²
The waste allowance covers cuts at the walls and the pattern. Typical allowances:
| Laying pattern | Waste |
|---|---|
| Straight | 5% |
| Diagonal | 10% |
| Herringbone | 15% |
Use your own allowances; tiles and some products need more.
Worked examples
Oak laminate at $14.95 per m², boxes of 2.2 m² ($32.89 a box):
| Room | Pattern | Area needed | Boxes | Price |
|---|---|---|---|---|
| 4 × 3.5 m (14 m²) | Straight, +5% | 14.7 m² | 7 (15.4 m²) | $230.23 |
| 4 × 3.5 m (14 m²) | Herringbone, +15% | 16.1 m² | 8 (17.6 m²) | $263.12 |
| 5 × 4.2 m (21 m²) | Diagonal, +10% | 23.1 m² | 11 (24.2 m²) | $361.79 |
With underlay at $3.50 per m² of room (14 m², $49.00) and edge trim at $6.00 per metre around the room (2 × (4 + 3.5) = 15 m, $90.00), the straight-laid 4 × 3.5 m room comes to $369.23.
In feet
A 12 × 15 ft room is 180 sq ft; with 10% waste it needs 198 sq ft. Boxes of 20 sq ft: 198 ÷ 20 = 9.9, so 10 boxes, 200 sq ft. At $3.49 per sq ft ($69.80 a box), that's $698.00.
Tiles
Porcelain tiles in boxes of 1.44 m², for a 3.6 × 2.8 m floor (10.08 m²) with 10% waste: 11.088 m² ÷ 1.44 = 7.7, so 8 boxes, 11.52 m². At $29.95 per m², $345.02.
Set it up with Trimsize
- Install Trimsize and, under What do you make?, choose Flooring & tiles. Your product gets ready-made pricing: the room's width and length in metres, a laying pattern (straight, diagonal or herringbone, with their waste), whole boxes of 2.2 m², four example floors, underlay and edge trim.
- Set your box size. The formula on the product uses 2.2 m² per box: change 2.2 to your box's coverage and check a room in the live preview. Use one product per box size. See Pricing editor.
- Set your floors and rates per m² (or sq ft), as materials. See Materials.
- Set the waste on each laying pattern, and show the patterns as tiles. See Tiles, cards and swatches.
- Add the block to the product page and place a test order.
Common mistakes
- Rounding the boxes to the nearest. 7.4 boxes is 8 boxes: always round up, after adding the waste.
- Adding waste to underlay and trim. Underlay covers the room and trim runs round it; price them on the room's own area and perimeter.
- Mixing box sizes on one product. Floors with different box sizes need different box maths: give each box size its own product.
Questions
Can customers enter their room size instead of a number of boxes?
Yes. They enter the room's width and length and choose a laying pattern, and the product page shows the price for the whole boxes they need.
How is the waste added?
Each laying pattern carries its waste percentage, for example 5% for straight and 15% for herringbone. The area is increased by it before rounding up to whole boxes.
Can I price underlay and trim separately?
Yes. Underlay can be a yes/no priced per square metre of the room, and edge trim a yes/no priced per metre of the room's perimeter.
Does it work in square feet?
Yes. Set the room size in feet and the rate per square foot, and use your box coverage in square feet in the formula.