Turf infill in Northeast Florida: sand, shell or rock — not rubber

Why the infill choice decides drainage on a Northeast Florida lot

Infill is the layer that decides whether a turf lawn drains or ponds. Rain travels through the infill, the backing and the base, and then it has to go into the ground — which in this part of Florida is where it stops. USDA soil survey data puts 71.4% of mapped acres in Duval, 78.5% in St. Johns and 82.2% in Nassau in the poorly or very poorly drained classes, and 75.7% of mapped St. Johns acres have the water table within six inches of the surface at some point in a normal year. NOAA's 1991-2020 normals put roughly 28.8 inches of rain on Jacksonville between June and September.

Florida's rule treats those layers as one system rather than as separate products. Paragraph (2)(d) requires subgrade materials to be washed before installation. Paragraph (4) requires permeability through the turf, the backing and the subgrade, and bars compacting the soil beneath the subgrade to the point that percolation suffers. Fines migrating out of a dirty base are what turn that stack into a lid.

What Florida allows, in the rule's own words

Rule 62-308.100, Florida Administrative Code, paragraph (2)(c): "Infill material, if used, shall only be clean silica sand, rock, shell, or other natural material, except that coated silica sand may be used provided that any coating used is non-toxic..." Two cross-referenced paragraphs go with it: (2)(a) prohibits heavy metals and intentionally added PFAS in the system, and (2)(b) requires it to be disposable at a landfill permitted under Chapter 62-701, F.A.C.

Check the scope before assuming it covers your job. DEP's FAQ: "This rule only applies to single-family residential properties that are 1 acre or less in size." Condominiums, duplexes, parks, athletic fields and commercial properties sit outside it, and so do private covenants — it "does not address HOA requirements, deed restrictions or other private property agreements." Nor is the state coming to look: DEP "does not issue permits" for turf and "is not implementing a permitting, inspection or enforcement program under this rule."

So what is the rule for? It is the standard that section 125.572, Florida Statutes, hangs its protection on. Subsection (3)(a) bars a local government from prohibiting synthetic turf on single-family residential property when that turf complies with the DEP standards adopted under the section. Put rubber infill in a back yard and the installation sits outside the state standard, so that protection does not attach and your city or county stays free to regulate it. Treat the rule as the floor you have to clear, not as permission.

Rubber gets exactly one place, and it is not your lawn

The same paragraph continues: "Rubber or any other synthetic infill material is allowed only within the footprint of playground equipment... Installation shall be designed to prevent washing away of any infill material off the residential property." It is not a crumb rubber ban. "Any other synthetic infill material" takes TPE and EPDM beads off a residential lawn too, and leaves them available under a swing set. Coated silica sand survives, if the coating is non-toxic.

There is a heat angle too. In studies collated by a 2024 systematic review, Petrass and colleagues measured SBR crumb rubber at 53.5°C against TPE at 45.6°C; Villacañas and colleagues measured SBR at 61.2°C against TPE at 58.0°C. Both differences were significant. The material Florida pushed out of residential yards is the hotter rubber, by 3.2°C to 7.9°C. A sand and organic plot in the same review measured 48.1°C — a different plot, not a head-to-head. Florida took away the hot option, not the cool one.

What actually decides how hot the surface gets

Artificial turf lacks the cooling provided by a living lawn's evaporation. Its surface temperature depends on sunlight, weather, the product and the installation. Changing the infill can affect measured temperatures, but it does not make a synthetic surface behave like natural grass. Plan shade around the hours when children, pets or other users will actually be on the lawn.

Brigham Young University researchers measuring adjacent surfaces across a day recorded a 7am-to-7pm average of 117.4°F on synthetic turf, 78.2°F on natural grass and 109.6°F on asphalt, with a peak of 200°F on a 98°F day. Hosing works, briefly: 174°F down to 85°F, back to 120°F after five minutes and 164°F after twenty.

Shade can substantially reduce surface heating, although the amount varies with the site and conditions. Bare feet, paws and skin in contact with the surface need particular attention. Similar air temperatures over two surfaces do not establish equal heat exposure, and shoes do not establish that turf is safe in hot weather. Plan cooler hours and shaded breaks, and stop using a surface that is too hot. Rinsing can cool turf temporarily; check conditions again as it reheats.

Plan care around the product and its use

Choosing an allowed infill does not settle maintenance. Ask for written care instructions covering the turf, infill and backing together, including waste removal, rinsing and compatible cleaning products. A frequently used pet area may need more attention than a putting green, and the drainage route needs to accommodate cleaning water as well as rain.

Before ordering, compare how each proposed material is maintained and replenished, what can wash out at edges, and how the installer will keep it on the property. If cleaning or disinfection is needed, follow the product's directions and confirm compatibility with the turf system. A laboratory comparison of infill materials does not establish a cleaning schedule or the level of infection risk on a family lawn.

What we can confirm, and what needs a phone call

The rule is adopted and in force. The Florida Administrative Code record for 62-308.100 gives an effective date of 5/19/2026 with the history note "History–New 5-19-26", and the adopted document carries the infill paragraph quoted above word for word. The Notice of Change during rulemaking recorded "(2) No change" against the proposed version, so the material-type and infill paragraphs reached adoption as published.

What we cannot tell you from a desk: whether your city or county has adopted its own turf ordinance alongside the state minimum, and whether your HOA or CDD documents mention infill at all. Those are phone calls to make before you order material. Strike one thing off the list now — nobody can sell you turf as Florida-Friendly Landscaping. The UF/IFAS publication defining that program says, "Because synthetic turf is not alive, it does not meet the criteria of a plant choice for an FFL landscape." Questions about infill for your yard? Call 303-349-2368.