How do you plan a multi-size opus layout and buy the right packs?
An opus layout combines several tile sizes in a set pattern. Follow the supplier’s drawing and count each size separately. If the tiles come in mixed-size packs, check how many pieces of each size are included. Four sizes do not mean four equal quantities.
Explanation
Start with the right drawing
Ask the supplier for the laying pattern for your tiles. It shows how to arrange a group of tiles, then repeat it. This group is called a module. A drawing found elsewhere may use different sizes or joints.
Try laying one complete group without adhesive. Check the actual tile sizes and gaps. If the pieces do not fit, check the measurements, their positions and the joints, then ask the supplier. Do not recut every tile of one size to force the pattern to fit.
Keep a count for each size
Write down how many large, medium and small tiles you need. Cuts along walls may use more of one size than another.
Do not compare square metres alone: a large tile covers more space than a small one. Having enough total area does not guarantee that you have all the right pieces.
Check how the tiles are sold
If each size is sold separately, calculate the boxes for each size. If they come as one mixed-size pack, check its exact contents.
Work out how many packs each size needs. Use the largest result, or you may run short of one size.
The tile layout planner includes opus patterns and lets you draw a repeating group. Keep the sizes separate in the quantities. The beginner’s guide explains how to go from the drawing to your purchases.
Formula / method
For each size: packs needed = tiles required ÷ tiles of that size in one pack.
If the result is not a whole number, round up. Repeat for each size, then keep the largest result. Your requirements must already include spare tiles. If a needed size is not included in the pack, buy it separately or choose another pack.
Concrete example
Simplified example: a pack contains 2 large tiles and 1 small tile. Your plan, including spares, needs 9 large and 6 small tiles.
For the large tiles: 9 ÷ 2 = 4.5, so 5 packs. For the small tiles: 6 ÷ 1 = 6, so 6 packs.
Buy 6 packs. You will have 12 large and 6 small tiles. Five packs would leave you one small tile short. This pack is made up to explain the calculation; it is not a laying pattern to copy.
Common mistake
Do not automatically allow 25% of each size for a four-size pattern. Do not rely only on the square metres listed on the packs: check the pieces they contain.
If sizes are sold separately, use the tile-box calculation for one size at a time.
Sources & methodology
Multi-size features: Outilo tile layout planner, checked on 3 October 2026. Pack formula and A/B example: original calculations. The laying diagram must come from the supplier of the actual product.
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