Why installing over concrete or asphalt can make sense

Retrofitting a hard surface with a safety-rated turf system avoids demolition, speeds up timelines, and delivers consistent performance when designed correctly. This approach works for schools, parks, daycares, rooftops, and multipurpose courts that need compliant fall protection and fast turnarounds.

Safety requirements: what must be proven

Critical fall height

Match the system to the highest designated fall height under and around equipment. The completed surface must meet the required fall height across use zones, not just on paper.

Performance criteria

  • ASTM F1292 compliance: HIC ? 1000 and Gmax ? 200 at the specified critical fall height.
  • Field testing after installation to confirm performance across representative test points.
  • Accessibility: design for ADA accessibility and test to ASTM F1951 where wheelchair access is required.

System design for hard, non-permeable bases

Shock pad selection

  • Use an engineered impact attenuation pad rated for the target fall height. Typical pad thickness ranges: about 25 mm for lower fall heights, thicker multi-layer or 55 mm-plus for higher fall heights. Select based on verified system data.
  • Choose pads with integrated drainage channels to move water laterally to drains.
  • Use components with documented durability for freeze-thaw, UV, and long-term compression.

Turf selection

  • Play-specific turf with tuft bind, stitch density, and fiber shape designed for high traffic and safety surfacing.
  • Perforated backing to aid drainage into the pad’s channels.
  • UV-stable, lead-safe materials that meet relevant safety guidelines.

Infill strategy

  • Use the infill type and depth specified for the tested system. Silica sand, elastomeric, or encapsulated infills may be used depending on the system.
  • Infill contributes to impact attenuation and surface stability. Do not substitute without validated data.

Drainage on concrete or asphalt

  • Surface slope: target 1 to 2 percent slope toward drains. Flat slabs need added drains or perimeter weeps.
  • Drainage path: combine a channeled pad, perforated turf, and accessible paths to surface or perimeter drains.
  • Control water at edges and terminations so it does not pond under the system.
  • Where moisture pressure is a risk, use compatible adhesives and detail to relieve vapor pressure.

Installation steps over concrete or asphalt

  1. Assess the site: confirm fall heights, measure slope, locate drains, note joints and cracks.
  2. Repair and prep: clean thoroughly, remove residues, fill spalls, and smooth sharp transitions. Allow the surface to dry.
  3. Plan drainage: confirm slope and drain locations. Add surface or trench drains if needed.
  4. Perimeter containment: install nailer boards or suitable anchoring points to lock the system and prevent creep.
  5. Pad layout: dry-fit the impact pad, align drainage channels, then adhere per manufacturer instructions. Seal pad seams as specified.
  6. Turf placement: roll out turf with pile direction aligned, trim, and position seams away from high traffic turns where possible.
  7. Seaming and bonding: use approved seam tape and adhesive. Maintain straight, tight seams with proper cure time.
  8. Infill installation: apply the specified infill in lifts and brush to level. Verify target depth and distribution.
  9. Detail edges and transitions: terminate cleanly at curbs, drains, and borders. Prevent trip edges.
  10. Field test: perform and document ASTM F1292 field testing at required locations and confirm pass results at the target fall height.

Edge, seam, and transition details that matter

  • Edges: secure against uplift with mechanical fasteners to nailers or with approved adhesives to curbs.
  • Seams: keep seams tight and level. Avoid locating seams at concentrated impact zones when possible.
  • Joints and cracks below: ensure pad spans joints without creating ridges. Treat large joints if needed to prevent telegraphing.

Special notes for concrete vs asphalt

  • Concrete: abrade or prime slick surfaces for better adhesion. Address expansion joints and ensure drains remain accessible.
  • Asphalt: allow new asphalt to cure before bonding. Use adhesives compatible with asphalt. Avoid high heat installation periods that can soften asphalt under point loads.

Maintenance and re-testing

  • Inspect seams, edges, and high traffic zones quarterly. Top off infill if levels drop.
  • Clean regularly to remove debris and fine particulates that can slow drainage.
  • Re-test impact attenuation after major modifications, severe weather events, or as required by your safety program.

Common mistakes to avoid

  • Skipping the impact pad or guessing thickness.
  • Assuming product certificates alone guarantee site compliance. Field results matter.
  • Ignoring drainage on a flat slab.
  • Using non-approved adhesives or seaming methods.
  • Leaving unanchored edges or exposed transitions.

Budget and timeline signals

  • Timeframe: a typical 1,000 to 2,000 square foot retrofit takes about 2 to 4 days depending on complexity and cure times.
  • Testing: schedule field testing immediately after installation while access is available for adjustments if required.

Specification support

Need a stamped system spec, fall height matrix, or detail drawings for your site? FusionTurf will help you select a proven pad and turf combination, detail drainage, and plan field testing so you pass the first time.