How cork and sand handle heat

Thermal conductivity

Cork is a natural insulator. Its thermal conductivity is typically around 0.04 W/mK. Dry silica sand is higher, commonly 0.2 to 1.0 W/mK depending on grain shape, packing, and moisture. Lower conductivity slows heat transfer to the surface and to your feet.

Evaporative cooling

Cork's cellular structure holds small amounts of surface moisture that can evaporate and cool the microclimate between fibers. Even a light rinse can amplify this effect during peak sun.

Mass and heat retention

Sand is dense and stores more heat per volume. Cork is lighter, so it tends to shed heat faster once shade or wind arrives, improving comfort sooner.

Real world expectations

In full sun, cork infill systems generally feel cooler to the touch than sand-only systems. The size of the gap is driven by design and weather, not a single magic number.

  • Turf color and fiber type influence how much solar energy is absorbed.
  • Infill depth and compaction affect how heat moves and how much backing is exposed.
  • Pile height and density change airflow at the surface.
  • Sun angle, clouds, wind, and humidity swing temperatures hour by hour.
  • Light irrigation or misting provides short bursts of cooling when needed.

Ways to reduce surface temperature

Choose the right infill strategy

  • Use 100 percent cork for maximum comfort, or blend cork with sand to balance ballast and cooling.
  • Maintain the specified infill level to keep fibers upright and reduce exposed backing.

Design and installation choices

  • Consider lighter turf colors or heat-reflective yarns where they fit the look.
  • Promote airflow with open layouts and avoid heat-trapping walls and dark hardscape.
  • Add shade where people linger, such as sails, pergolas, or trees.

Operational tips

  • Mist or rinse surfaces during peak heat for fast, temporary cooling.
  • Schedule heavy use for mornings or late afternoons on extreme heat days.

Pros and cons beyond temperature

Cork infill

  • Pros: cooler-touch potential, renewable material, light weight, solid shock absorption.
  • Considerations: higher upfront cost than sand, periodic top-offs, manage wind during install.

Sand infill

  • Pros: low cost, easy to source, strong ballast and tuft lock.
  • Considerations: can feel hotter in peak sun, heavier to handle, may compact without maintenance.

Specification quick guide

  • Applications: landscapes, play areas, rooftops, and light-use fields can use cork or cork blends. High-wind or high-traffic sites may benefit from blended systems.
  • Target infill levels: follow your turf model specification. Many landscape systems run about 1.0 to 2.5 pounds per square foot total infill. Cork's lower density means more volume for the same weight.
  • Material quality: choose kiln-dried, screened cork sized for your turf gauge. For sand, use washed, rounded silica with proper gradation.

When cork makes the most sense

Choose cork where barefoot comfort matters, like pool surrounds, play spaces, rooftops, and sunny courtyards. For pet-heavy installs, blend cork with odor-control infills such as zeolite to manage ammonia while preserving cooler feel.

Decision checklist

  • Your top priority is comfort under strong sun.
  • Local climate has long, hot, dry afternoons.
  • You can maintain correct infill depth and occasional top-offs.
  • You need ballast for wind or traffic and can use a cork plus sand blend.