Polymeric Sand Calculator
Polymeric sand bags claim wildly optimistic coverage because coverage depends on your joints, not your square footage: tight-jointed pavers use half the sand of irregular flagstone. This calculator asks about your paver type first and then converts your patio area into a realistic 50 lb bag count.
How this calculator works
Bags = area ÷ coverage rate for your joint profile, rounded up. The rates (100 / 80 / 50 / 30 sq ft per 50 lb bag) reflect manufacturer charts for typical 2 3/8" thick pavers. Apply only to a bone-dry surface, sweep diagonally into joints, compact, sweep again, then mist in controlled passes — water activates the polymers, and haze on paver faces is permanent.
Frequently asked questions
How many square feet does a bag of polymeric sand cover?
Anywhere from 30 to 100+ sq ft per 50 lb bag. Tight-jointed interlocking pavers: 85–100 sq ft. Standard 1/4" joints: 75–85. Flagstone with inch-wide joints: as little as 20–30. This is why two neighbors with same-size patios can need wildly different amounts.
Why did my polymeric sand fail or wash out?
Almost always water: the surface or joints were damp during install, it rained within 24 hours, or the initial misting flooded the joints and washed the polymer out. Joints also need at least 1" of depth to lock — shallow-filled joints crumble within a season.
Polymeric sand vs regular sand for paver joints?
Polymeric costs 5–10× more per bag but hardens against weeds, ants, and washout, lasting 5–10 years. Regular joint sand needs sweeping back in every year and invites weeds. For a patio you want to forget about, polymeric wins; for a temporary path, save the money.