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Calculating Tile & Slab Wastage for Architectural Layouts
ArchéTile Design Desk February 12, 2026 4 Min Read
### Why Standard 10% Wastage Fails for Porcelain Slabs
When specifying 60×60cm tiles, ordering 10% extra is usually sufficient. However, for 120×240cm or 160×320cm slabs, ordering 10% extra can leave a project short of material or cause unnecessary expense.
### Factors Influencing Wastage
- **Slab Module vs. Room Width**: If a living room measures 4.5 metres wide and you lay 1.2 metre slabs, you will have 3 full slabs (3.6m) and a 0.9m cut slab. The remaining 0.3m offcut cannot be used elsewhere in the main view area. - **Book-Matched Pattern Alignment**: Matching continuous marble veins requires ordering full sequential slabs from the same production batch. - **Niches and Window Jam Recesses**: Mitred window reveals generate higher offcut ratios.
### ArchéTile CAD Layout Service
We provide architects with preliminary CAD layout reviews to calculate exact slab counts, cut maps, and minimal wastage percentages prior to ordering material.
When specifying 60×60cm tiles, ordering 10% extra is usually sufficient. However, for 120×240cm or 160×320cm slabs, ordering 10% extra can leave a project short of material or cause unnecessary expense.
### Factors Influencing Wastage
- **Slab Module vs. Room Width**: If a living room measures 4.5 metres wide and you lay 1.2 metre slabs, you will have 3 full slabs (3.6m) and a 0.9m cut slab. The remaining 0.3m offcut cannot be used elsewhere in the main view area. - **Book-Matched Pattern Alignment**: Matching continuous marble veins requires ordering full sequential slabs from the same production batch. - **Niches and Window Jam Recesses**: Mitred window reveals generate higher offcut ratios.
### ArchéTile CAD Layout Service
We provide architects with preliminary CAD layout reviews to calculate exact slab counts, cut maps, and minimal wastage percentages prior to ordering material.
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