Tile adhesive calculator: how much tile adhesive you need
The calculator needs JavaScript. The worked example, formula and figures below show exactly how it works, so you can do the sum yourself. A guide, not advice. Check your supplier's or maker's figures before ordering.
Short answer
Worked example
| You enter | Value |
|---|---|
| Area to tile | rectangle 4 m × 3 m |
| Wall or floor | Floor |
| Trowel notch | 10 mm |
| Coverage from the bag for your notch | 4 kg/m² |
| Bed | Solid bed |
| Bed factor | 1 × |
| Waste allowance | 10% |
| Bag size | 20 kg |
Order: 3 × bags of tile adhesive (52.8 kg)
| Result | Value |
|---|---|
| Adhesive bags | 3 |
| Adhesive | 52.8 kg |
| Adhesive per m² (with bed factor, before waste) | 4 kg/m² |
| Area (after openings) | 12 m² |
Show the working
- Area: 12 m²
- Coverage: 4 kg/m² (from your bag)
- Adhesive: 12 m² × 4 kg/m² × 1 (bed) × 1.1 (10% waste) = 52.8 kg
- Bags: 52.8 kg ÷ 20 kg, rounded up = 3
How it works
- Adhesive (kg) = area (m²) × coverage for your trowel notch (kg/m², from the bag) × bed factor × (1 + waste)
- Bags = kg ÷ bag size, rounded up
- Primer (L) = area ÷ primer coverage (m²/L, from the bottle)
Coverage depends on the product and the notch: the bag or the maker's chart is the figure to use.
Large-format tiles usually need back-buttering as well as a notched bed; follow the adhesive maker's guidance.
Our default (adjustable)
These are typical planning figures and our own allowances, not facts about your product. Change any of them in the calculator to match your bag, pack or tin.
| Figure | Our default (adjustable) | Kind | Source |
|---|---|---|---|
| Coverage from the bag for your notch | Enter from the bag, pack or tin | Typical value Not yet checked against the source | From your product Depends on the product and trowel notch; read the bag or maker's chart. |
| Bed factor: Standard notched bed | Enter from the bag, pack or tin | Our assumption Not yet checked against the source | Our choice: change it to suit your job Researcher to source from adhesive makers (Mapei, BAL, Ardex). |
| Bed factor: Solid bed | 1 × | Our assumption Not yet checked against the source | Our choice: change it to suit your job brief v2 TA1 (solid-bed factor 1.0). Researcher to confirm against adhesive makers' charts. |
| Bed factor: Back-buttered | Enter from the bag, pack or tin | Our assumption Not yet checked against the source | Our choice: change it to suit your job Researcher to source from adhesive makers (Mapei, BAL, Ardex). |
| Waste allowance | 10 % | Our assumption Not yet checked against the source | Our choice: change it to suit your job brief v2 TA1 (10%). |
| Bag size | Enter from the bag, pack or tin | Common UK size Not yet checked against the source | From your product Enter from the bag. |
| Primer coverage | Enter from the bag, pack or tin | Typical value Not yet checked against the source | From your product From the primer bottle. |
| Tile side above which the maker says to back-butter | To be confirmed from the source | Regulation or HSE figure Adhesive maker's guidance on large-format tiles (back-buttering) Not yet checked against the source | Source to be added by the Researcher brief v2 T1. Researcher to source the tile size above which makers say to back-butter. |
Regulations and standards
These are UK figures.
| Table | Clause | Nations | Status |
|---|---|---|---|
| Tile adhesive coverage by trowel notch | Adhesive makers' coverage charts (e.g. Mapei, BAL, Ardex): product-specific | UK-wide | 0/4 values entered Not yet checked against the source |