Thin-Set Mortar Coverage
The bags of thin-set a tile job needs, sized off the trowel notch the way a setter buys it.
Example
You enter
- Area to tile (sq ft) 200
- Square-notch trowel quarter_three_eighths
- Bag weight (lb) 50
- Waste (%) 10
You get
- Coverage per bag 63 sq ft
- Bags 4
Checked against published worked examples from: Custom Building Products.
Details, formula, and sources
Scopea 1/4 in notch covers about twice the area of a 1/2 in notch.
Formula or tableCoverage per bag from the square-notch trowel (~95 / 63 / 45 sq ft for 1/4 / 1/4x3/8 / 1/2 in); bags = ceil(area x (1 + waste) / coverage).
Source and editionManufacturer thin-set coverage charts (Custom Building Products / Mapei / Laticrete, by name); ANSI A108 mortar-contact minimum.
Free accessCoverage charts free at the maker's technical pages.
What governsEstimate. AHJ and licensed professional govern.
API field namesarea_sqft, trowel, bag_weight_lb, waste_pct, cov_per_bag, bags
- Mortar contact ANSI A108 ~80% dry / 95% wet or exterior (do not stretch a bag)ANSI A108