How to define the greenest playground infill

Green is not a vibe, it is a checklist. Use these criteria to rank infills for playground turf:

  • Material origin and renewability
  • Chemical safety and low VOCs
  • Microplastic risk and particle migration
  • Embodied carbon and transport footprint
  • Thermal performance in sun
  • Drainage behavior and leaching profile
  • Durability, reuse, and end-of-life options

Why cork and coated sand rise to the top

Cork infill

Cork is harvested from bark, not trees, and regrows. It is light, clean, and naturally cooler under sun exposure compared to dark rubber infills.

  • Pros: renewable feedstock, low odor, low VOC, cooler surface temps, comfortable feel
  • Considerations: lightweight particles can migrate without proper containment, top off as needed after heavy use or storms, specify kiln dried and screened grades
  • Best fit: nature themed or heat sensitive playgrounds where sustainability is a visible priority

Coated sand infill

Coated sand starts with inert silica and adds a stable, bound coating for better consistency and cleanliness. It stays put, supports fiber stand up, and resists compaction.

  • Pros: inert core, excellent stability, low dust when properly graded, predictable maintenance, optional antimicrobial variants
  • Considerations: heavier feel than cork, can run warmer than cork but far cooler than black rubber infills, specify rounded, well graded media
  • Best fit: high traffic playgrounds seeking low migration and consistent play performance

Safety first: impact performance and accessibility

Infill choice matters, but the shock pad and full system drive fall protection.

  • Target results per ASTM F1292: HIC at or below 1000 and gmax at or below 200 for the critical fall height of your equipment
  • Verify third party lab data for the exact turf plus pad plus infill system, not just components
  • Confirm field testing at install and on a maintenance schedule
  • Check ADA accessibility using ASTM F1951 for mobility performance across the surface

Infill primarily tunes surface feel, fiber support, and thermal profile. It does not create fall height on its own. Size the pad first, then dial infill loading to hit the spec.

Spec guide: start points that work

  • Up to 5 ft fall height: 10 to 12 mm shock pad, cork or coated sand at roughly 2.0 to 3.0 lb per sq ft
  • 6 to 8 ft fall height: 20 to 25 mm shock pad, similar infill loading adjusted by lab tuning
  • 9 to 12 ft fall height: 30 to 35 mm shock pad, confirm full system lab curves before approving

Always request the HIC curve for your exact system and fall height, plus the maintenance plan that keeps those numbers locked in over time.

Heat, drainage, and day to day upkeep

  • Heat: Cork typically runs cooler in full sun, often 10 to 20 F lower versus dark rubber infills. Coated sand is stable and avoids extreme heat spikes.
  • Drainage: Both allow fast water flow through modern turf backings and base designs. Coated sand will not float. Cork is light, so proper edging and grooming matter after severe storms.
  • Maintenance: Brush and decompact on a schedule, top off infill where needed, and keep a post install test cadence for HIC and gmax.

Environmental footprint snapshot

  • Cork: rapidly renewable harvest, low embodied energy, minimal additives, potential for reuse or energy recovery at end of life when kept clean
  • Coated sand: abundant mineral core with a thin, bound coating, very low microplastic shedding risk, long service life, can be reclaimed and repurposed
  • TPE or EPDM elastomers: durable and clean performing, but higher embodied carbon than cork or coated sand, useful when additional resilience is required

Cost and availability

Relative cost tiers vary by region and spec. In general: cork is moderate, coated sand is moderate to moderately high, TPE and EPDM sit higher. Typical playground turf uses about 2.0 to 3.5 lb of infill per sq ft. Ask for delivered cost per pound and estimated pounds per project area to compare apples to apples.

Procurement checklist

  • Full system lab report with ASTM F1292 HIC and gmax for your fall height
  • ASTM F1951 accessibility report
  • Infill SDS and third party material safety data
  • Sourcing transparency: for cork, look for responsible harvest certifications; for coated sand, coating chemistry disclosure
  • Maintenance plan with inspection intervals and top off guidance

Get a precise spec from FusionTurf

Send your fall heights, square footage, and climate. We will lock in a cork or coated sand spec with the right pad thickness, provide current lab data, and deliver a clear maintenance schedule.