A Longitudinal Study of Playground Surfaces to Evaluate Accessibility - Final Report

Site Profiles by Surface Type

The surface categories selected for the study were purposefully designated based on their widely accepted perceived attributes as both safe and accessible.  New playground sites were brought into the study each year as they were constructed and identified by the playground owners.  Some playground sites were surfaced with one surface material/system while others were surfaced with a combination of two surface materials/systems.  Table 1 provides a profile of the number of sites installed within each surface category.

Markedly absent from the Table 1 of playground sites and the study were locations with shredded rubber surfacing.  Public park playgrounds with shredded rubber surfacing were difficult to locate through direct recruitment with playground owners.  Thus, requests for assistance identifying Midwest sites were made to the three major shredded rubber manufacturers and the international member association.  None of the representatives from the major manufacturers or association responded to repeated requests from the research team.  Finally during the last year of the study, six new installations with shredded rubber were identified with one agency.  Two days prior to the first site visit, the agency pulled out of the study with concerns for how the surface material would perform.  As such, public park playground installations with shredded rubber surfacing are not represented in this study.

The participating playground sites ranged from 2,300 sq. ft. to 12,500 sq. ft.  The costs for surfaces, materials and installation, ranged from less than $1/sq. ft. to $21/sq. ft. Table 2 provides a profile of each playground, the installation date, total area, surface area, cost for equipment and cost for surfaces. 

Of the sites evaluated, nine were surfaced entirely with poured in place rubber (PIP).  It should be noted that seven of the sites were traditional PIP installations comprised of two layers, a wear layer with larger rubber particles and a custom top layer with granular particles.  Two sites were installed as one layer comprised of bonded large particle rubber shreds. The surface cost for PIP ranged from $6.59/sq. ft. to $19.80/sq. ft.  The wide range of cost per sq. ft. can be attributed to the fact that PIP is often sold on a sliding scale, the more material purchased, the cheaper the unit cost.  The cost for PIP has also been dramatically affected over the last five years due to volatility in the petroleum market.

There were two sites surfaced completely with tiles (TIL).  Traditionally TIL are constructed of bonded rubber, similar to PIP, but designed as 2 ft. x 2 ft. squares with interlocking sides.  They are marketed as easier to install with more flexibility than PIP should they need to be reconfigured to accommodate new playground equipment.  The cost for TIL ranged from $8.96/sq. ft. to $21/sq. ft.  TIL was the most expensive of the five types of surfaces identified for study.  This can be attributed to the number of small surface area installations where the use of TIL was less than 2,000 sq. ft.  These installations limited the use of the TIL to connect the accessible route from the playground perimeter to the transfer system of the elevated composite structure.  The remainder of the larger play area was surfaced with a loose fill material.     Similar to PIP, the product is sold on a sliding scale and the cost has also been affected by price fluctuations in the petroleum market.

There were six sites surfaced entirely with engineered wood fiber (EWF).  In addition, there were five sites surfaced with a combination PIP and EWF, and eight sites surfaced with a combination TIL and EWF.  The EWF ranged in cost from $ .74/sq. ft. to $2.50/sq. ft.  A design trend has emerged over the last 15‒20 years whereby a unitary surface, such as PIP or TIL, is used as the primary accessible route to accessible equipment and the remainder of the equipment use zones is surfaced with a less costly loose fill material such as EWF or shredded rubber (SHR).  While this may be viewed as a cost effective compromise to surface selection, the use of the loose fill material with some unitary systems has had a negative effect on the surfaces, which will be described later in this study.

There were a total of five sites with four different hybrid (HYB) surface systems evaluated in the study.  One site used an outdoor carpet over engineered carpet padding infilled with silicone sand.  Two sites used a system where the base consisted of 2 ft. x 2 ft. pillows filled with shredded rubber and covered by 5 ft. wide rubber top mats, resembling melted spaghetti, affixed at the seams similar to how carpet is seamed together.  The remaining two sites used an artificial turf grass system, similar to that used on football fields.  The HYB surface systems ranged in cost from $7.50/sq. ft. to $12.65/sq. ft.