Tile planning
How Much Thinset and Grout Do I Need for Tile?
A 50 lb bag of thinset covers roughly 80 to 100 square feet with a 1/4 inch square-notch trowel, 60 to 70 square feet with a 1/4 x 3/8 inch notch, and 40 to 50 square feet with a 1/2 inch notch. Grout varies too much for one number, so use the chart on the bag.
Open the tile calculatorThinset coverage by trowel size
Bigger tiles need a deeper mortar bed to get full contact, so they use a larger trowel notch and more thinset per square foot. These are typical label ranges for a 50 lb bag.
| Trowel notch | Typical tile size | Coverage per 50 lb bag |
|---|---|---|
| 1/4 x 1/4 in square | Up to about 8 in | 80 to 100 sq ft |
| 1/4 x 3/8 in square | About 8 to 16 in | 60 to 70 sq ft |
| 1/2 x 1/2 in square | 16 in and larger | 40 to 50 sq ft |
How many bags of thinset by area
Divide the area by the coverage range for your trowel and round up. The lower count assumes the high end of the label range, the higher count the low end. Buy the higher count for large tiles and uneven floors.
| Area | 1/4 x 1/4 in notch | 1/4 x 3/8 in notch | 1/2 x 1/2 in notch |
|---|---|---|---|
| 30 sq ft | 1 bag | 1 bag | 1 bag |
| 50 sq ft | 1 bag | 1 bag | 1 to 2 bags |
| 100 sq ft | 1 to 2 bags | 2 bags | 2 to 3 bags |
| 200 sq ft | 2 to 3 bags | 3 to 4 bags | 4 to 5 bags |
| 500 sq ft | 5 to 7 bags | 8 to 9 bags | 10 to 13 bags |
| 1,000 sq ft | 10 to 13 bags | 15 to 17 bags | 20 to 25 bags |
A worked thinset example
A 60 square foot bathroom floor in 12 x 24 inch tile uses a 1/2 inch notch. At 40 to 50 square feet per bag, one bag will not finish the job, so buy two. Back-buttering large tiles, which most manufacturers recommend, uses a little more.
Estimating grout
Grout use depends on four things: tile length, tile width, tile thickness, and joint width. Small tiles with wide joints use many times more grout than large tiles with tight joints, so a single rule of thumb is unreliable.
The joint volume per square foot is (tile length + tile width) / (tile length x tile width) x 144 x joint width x tile thickness, in inches. The table converts that volume to pounds at roughly 0.06 lb per cubic inch of sanded grout and rounds it, so treat it as a starting point and confirm with the chart on your bag.
- Use the coverage chart on the grout bag or the manufacturer calculator with your exact tile and joint size.
- Mosaics and small subway tile can use several pounds of grout per 10 square feet.
- Large-format floor tile with 1/8 inch joints often needs only one small bag for a whole bathroom.
- Sanded grout is for joints 1/8 inch and wider. Unsanded is for narrower joints and easily scratched tile.
| Tile size and thickness | Joint width | Grout per 100 sq ft |
|---|---|---|
| 12 x 24 in, 3/8 in thick | 1/8 in | About 5 lb |
| 12 x 12 in, 3/8 in thick | 1/8 in | About 7 lb |
| 12 x 12 in, 3/8 in thick | 3/16 in | About 10 lb |
| 6 x 6 in, 5/16 in thick | 1/8 in | About 11 lb |
| 3 x 6 in subway, 5/16 in thick | 1/16 in | About 8 lb |
| 2 x 2 in mosaic, 1/4 in thick | 1/8 in | About 27 lb |
The rest of the starter list
Add spacers or a leveling system, edge trim for exposed tile edges, a mixing bucket and paddle, a margin trowel, a grout float, sponges, and sealer if the tile or grout calls for it.
Wet areas are a different project. A shower or tub surround needs a complete waterproofing system behind the tile, installed to the manufacturer instructions. Tile and grout alone are not waterproof.
- Thinset coverage falls as trowel notch size goes up.
- Size grout from the bag chart using your tile and joint dimensions.
- Showers need waterproofing behind the tile, not just tile and grout.
Run the numbers
The Tile Calculator applies this math to your own measurements and shows each step. Best for planning a bathroom floor, laundry room, backsplash, or entryway tile job.