Substrate preparation
Localised smoothing may add £5–£12/m², while extensive levelling or remedial screeding can add £15–£35/m².
Tile selection
Premium porcelain, stone or specialist finishes can increase the installed rate by £25–£100/m² through higher material cost and slower cutting.
Tile format
Large-format units typically add 15–35% because of handling, bedding tolerances and levelling-system requirements.
Layout complexity
Diagonal, herringbone or multi-size patterns commonly increase fixing costs by 15–30% through additional setting out and waste.
Movement joints
Proprietary movement joints and perimeter details generally add £8–£20 per linear metre depending on profile and substrate conditions.
Access and phasing
Small workfaces, out-of-hours working or multiple visits can increase rates by 10–25% owing to reduced output and repeated mobilisation.