Artificial grass looks finished and plays well only when what lies beneath it is built right. This guide walks through infill, drainage and base preparation for residential and commercial turf installation across Los Angeles and surrounding areas, from the flat basin and the hot San Fernando Valley to the hillside neighborhoods and beach communities. Whether your yard is on compacted caliche, clay, sand or concrete, the foundation determines whether your turf stays flat, drains properly, resists odor and lasts.
You will find here the details that separate a thorough installation from a quick lay-down on bare dirt: what infill does and how much you need, how to excavate and compact a base, why drainage matters in a monsoon downpour or a dog run, and what to ask for in writing. This is the information you need to evaluate any turf installer, including us, and to understand why the cheapest bid is often the most expensive mistake.
Turf Infill Options: Silica, Coated Sand, Zeolite and Envirofill
Infill is the granular material spread across the turf after installation. It serves four essential functions: it props the synthetic fibres upright so they look and play like real grass, it protects the backing from ultraviolet light, it adds weight to keep the turf from shifting, and it helps water drain through the system. The most common infill is silica sand, a basic ballast that is inexpensive and effective. Coated sand is silica that has been rounded and often colored, making it gentler on skin and eyes during play and giving turf a warmer or more natural appearance than raw silica alone.
Zeolite is a porous mineral that absorbs and neutralizes ammonia and odors, making it popular for pet areas and dog runs where urine concentration is high. Antimicrobial and cooling coated infills, such as Envirofill, are engineered to inhibit bacterial growth and reduce surface temperature in direct sun. Crumb rubber, made from recycled tires, is standard in sports fields and athletic courts where shock absorption and performance matter, but it is rarely used in residential yards because of cost, heat retention and odor concerns in warm climates. Most residential and pet installations use silica or coated sand, often blended with zeolite where odor control is a priority. The choice depends on the use, the climate and your budget, and it should be named in your written specification.
How Much Infill Artificial Grass Needs, and Why
Infill is specified in pounds per square foot, and this number is critical. The infill weight holds the fibres erect, protects the backing from sun exposure, and affects drainage and performance. Too little infill is one of the most common shortcuts in cheap installations. A turf with insufficient infill will mat down under foot traffic, expose the backing to UV degradation, fail to drain properly, and develop odor problems in pet areas because urine pools on the backing rather than draining through. Typical residential turf requires between 1.5 and 2.5 pounds of infill per square foot, depending on the pile height, fibre denier and intended use. Pet and play areas may need more. A putting green requires precise infill weight and distribution for consistent ball roll. Always ask for the infill amount in writing, and verify that the installer is using the full specification, not cutting corners to reduce material cost.
The infill specification should also state the type of material, the grain size, and any additives such as zeolite or antimicrobial coatings. A complete written spec protects you because it creates accountability. If the turf begins to mat, drain poorly or develop odor within a year, a written spec makes it clear whether the installer met the agreed standard or fell short. Request a sample of the infill before installation begins, so you can see and feel what is going under your turf.
What to Put Under Artificial Grass for Drainage
The foundation of artificial grass begins with removal. If you have an existing lawn, it must be stripped away entirely, including roots, dead thatch and debris. If old turf is being replaced, it is cut up and hauled off. Any remaining organic material will decompose beneath the new turf, creating voids, settling and eventual dips. Once the site is cleared, the ground is excavated to the depth required by the base specification, typically three to four inches. A weed barrier, usually a non-woven geotextile, is then laid down. This barrier prevents soil from migrating up into the base and weeds from growing through from below, but it still allows water to drain downward. In some cases, such as a yard with poor drainage or a history of standing water, the weed barrier may be omitted or replaced with a more permeable option after the drainage problem is addressed.
Next comes the base layer, almost always decomposed granite or crushed base rock in Los Angeles. This material is spread and compacted in lifts, typically three to four inches total, using a plate compactor to achieve firm, even density. Compaction is essential. An uncompacted base settles unevenly, creating low spots where water pools and odor concentrates. On hard surfaces such as concrete, patios or balconies, the turf is never glued flat to the slab. Instead, a draining underlay or pad is installed first, allowing water to flow beneath the turf to an edge drain or to the perimeter. This prevents standing water, odor and deterioration of the backing. For pet turf and dog runs, an underlay also protects the backing from direct contact with urine.
Base Prep on Los Angeles Caliche: Excavation, Base Rock and Compaction
Los Angeles soil is often hard, compacted caliche and clay that does not drain naturally. Caliche is a calcium carbonate layer that can be impermeable, and it is common in the basin and the Valley. When artificial grass is installed over caliche or clay without proper base preparation, water has nowhere to go. It pools beneath the turf, creating odor, bacterial growth, and eventual deterioration of the backing and seams. The solution is excavation and replacement. The existing soil and caliche are removed to the depth required by the turf specification, typically three to four inches. The excavated area is then graded with a slight fall, sloping away from the house and away from any pool or structure, so that water naturally moves away from the foundation. This grading is critical in Los Angeles, where even brief heavy rains or a broken irrigation line can saturate a yard.
Once graded, the base is built up with decomposed granite or crushed base rock, spread in lifts and compacted firmly with a plate compactor after each lift. Proper compaction creates a dense, stable platform that does not settle or shift under foot traffic. An uncompacted base is one of the most common causes of early failure: the turf develops dips and low spots where water pools, infill migrates, seams lift, and odor concentrates. If your yard has a genuine water problem, such as a high water table, poor subsurface drainage, or a history of flooding, this must be addressed before turf is installed. A French drain, a sump, or a regrading of the entire yard may be necessary. We will assess the drainage situation on site and will decline the job if the water problem cannot be solved with base preparation alone. Doing it right the first time prevents costly repair or replacement later.
Artificial Grass Drainage and Underlay: Perforated vs Fully Permeable
Artificial turf is only as good as its drainage system. Water must move through the turf, through the infill, through the backing, and away from the installation. The backing of the turf itself is either perforated (with small holes punched through it) or fully permeable (allowing water to flow through the material itself). Drainage rate is measured in gallons per hour per square foot, and a faster rate is generally better. A typical residential turf might drain at 15 to 20 gallons per hour per square foot, while a pet or play area might drain faster. However, a fast-draining turf is useless if the base beneath it does not drain. This is where many cheap installations fail: the turf is permeable, but it sits on uncompacted soil or clay that holds water like a bathtub. Water pools under the turf, odor builds up, and the backing deteriorates.
For hard surfaces such as concrete, patios, balconies and rooftops, an underlay or drainage pad is essential. This pad creates an air gap between the turf and the hard surface, allowing water to flow to the perimeter and drain away. Without an underlay, water sits on the concrete, the backing stays wet, and odor and mold develop. For pet turf, the drainage rate is tested in the real world: a dog run in the San Fernando Valley can receive heavy urine concentration and occasional downpours. The turf and base must drain faster than the water arrives, or odor and bacterial growth will follow. Request the drainage rate in gallons per hour per square foot in your written spec, and ask how the base will be prepared and compacted. A good installer will explain both the turf backing and the base in detail, because drainage is not an afterthought, it is the foundation of the system.
Seams, Nails, Edging and Power Brooming
The details that separate a professional installation from a careless one show up in the seams, edges and finishing work. Seams are joints where two pieces of turf meet. A proper seam is joined with seam tape and a polyurethane or similar adhesive applied to both sides of the tape, pressed firmly into place, and allowed to cure. The grain of the turf (the direction the fibres lean) should be aligned across the seam so the two pieces look like one continuous surface. A visible seam, a ridge where the tape pulls up, or a seam that separates within the first year tells you the adhesive was not applied correctly, the tape was not pressed down, or the curing time was not respected. Nails or staples hold the perimeter of the turf in place, typically spaced 6 to 12 inches apart depending on the product and the site. Poor spacing or nails driven too deep can tear the backing; too few fasteners allow the turf to shift and seams to lift.
Edges are the perimeter where the turf meets the landscape. A clean edge is cut tight to pavers, sidewalks or structures, and the perimeter is secured with bender board, landscape edging or a nailed perimeter that is flush and stable. Lifted edges, especially at seams, are a sign of inadequate fastening or base settlement. Power brooming is the final step: the turf is brushed vigorously with a stiff brush or a power broom to stand the fibres up, spread the infill evenly, and give the surface a natural appearance. Without power brooming, the turf looks matted and flat. Proper power brooming takes time and skill, and it is often skipped by hurried installers. Ask to see photos of finished work, and look closely at the seams, edges and overall appearance. These details matter because they determine how the turf looks and how long it lasts.
What a Written Turf Spec Should Include
Before any work begins, you should have a written specification that names every material and every step of the installation. This document is your protection and your proof. It should include the turf product name and fibre type (polyethylene, polypropylene or nylon), the face weight in ounces per square yard, the pile height in millimeters, the backing type and its drainage rate in gallons per hour per square foot, the infill type and the infill weight in pounds per square foot, the base material and base depth in inches, the compaction standard, whether a weed barrier will be used, the seam method and edge treatment, cleanup and haul-off, and the workmanship warranty period. The spec should also note any site-specific conditions, such as grading for drainage, removal of existing turf or concrete, or edge details around pavers or structures.
A written spec is not a sales promise; it is a technical document that holds both you and the installer accountable. If the turf fails to drain, you can refer to the drainage rate in the spec. If it settles or develops dips, you can check the base depth and compaction standard. If seams lift or separate, the spec defines the seam method and the warranty period. Before you commit to any installation, request a detailed written spec, review it carefully, and ask questions about anything you do not understand. Request a free estimate from us, and we will provide a full specification and a site visit to measure and assess your yard. For more information on pricing and what to expect, visit our pricing page. A good turf installer will give you this spec without hesitation because it reflects honest work and honest materials.