Artificial grass looks alive and plays well only when the ground beneath it is built right. Infill, base preparation, and drainage are invisible to visitors, but they determine whether your turf stays flat, drains fast enough for San Diego's rare downpours, resists pet odor, and lasts years without lifting seams or settling into dips. This guide walks you through each layer, from soil excavation through the finished surface, so you understand what separates a solid installation from a shortcut job that fails within a season.
Whether you are installing turf in a North Park bungalow yard, a Rancho Bernardo backyard with a pool surround, a dog run in Clairemont, or a commercial property anywhere in San Diego and the surrounding areas, the same principles apply: hard caliche soil must be excavated and replaced, base rock must be compacted firmly, infill must be specified in writing, and seams must be sealed and power broomed. Read on to learn what to ask for and what to inspect.
Turf Infill Options: Silica, Coated Sand, Zeolite and Envirofill
Infill is the granular material that sits on top of the turf backing, between and around the grass fibres. It serves four jobs: it props the fibres upright so they look and feel natural, it protects the backing from ultraviolet light, it adds weight so the turf does not shift in wind or under foot traffic, and it helps water drain through the system. The type and amount of infill you choose affects performance, durability, and how the turf feels underfoot.
Silica sand is the baseline infill, inexpensive and effective as a ballast. It is angular, so it does not roll or compact easily, and it drains well. Coated sand is silica sand treated with a polymer or mineral coating that rounds the grains, making them gentler on skin and easier to rake. Coated sand also comes in colours that can match or complement your turf choice. Zeolite is a porous mineral that absorbs and neutralizes ammonia and other odor molecules, making it popular for pet turf and dog run installations. Antimicrobial and cooling coated infills, such as Envirofill, add a polymer layer that inhibits bacterial growth and can lower surface temperature in full sun. These premium infills cost more but perform well in high-traffic areas and pet yards. Crumb rubber, made from recycled tires, is standard on sports fields and synthetic turf courts where impact absorption matters, but it is not typical for residential yards and is not recommended where pets or children play on the surface regularly.
Your installer should recommend an infill based on your use case, the turf product you choose, and your local conditions. Ask for the infill type and brand in your written specification.
How Much Infill Artificial Grass Needs, and Why
Infill is measured in pounds per square foot (psf), and the amount matters as much as the type. A typical residential turf installation calls for 2 to 4 psf of infill, depending on the pile height, face weight, and backing of the turf you select. Heavier, denser turfs need more infill to prop up the fibres and protect the backing. Pet yards and play areas may call for slightly more infill to cushion impacts and help with drainage. Your installer should calculate the infill amount based on the specific turf product and the square footage of your yard, then state it in writing before work begins.
Infill does three critical things: it holds the fibres vertical so they do not mat down, it shields the backing from sunlight (which degrades the latex and polypropylene over time), and it adds dead weight that keeps the turf from buckling or shifting. Too little infill is a common shortcut in cheap installations. Without enough infill, the fibres flatten quickly, the backing degrades faster, and the turf feels thin and flimsy underfoot. You may also see sand or infill washing out during rain if the base does not drain and the turf is not compacted properly. Demand the infill amount in pounds per square foot in your written estimate, and ask your installer to show you the calculation.
What to Put Under Artificial Grass for Drainage
The foundation under artificial grass must drain freely, sit level, and be firm enough that foot traffic and equipment do not compress it after installation. Start by removing the existing lawn, sod, or old turf and all roots and organic debris. Roots left in place will decompose, creating voids and soft spots that cause the turf to settle unevenly. Once the old surface is gone, excavate the area to a depth determined by your base material and the finished grade you need. In most San Diego yards, this means digging 3 to 4 inches deep, though steeper slopes or areas prone to pooling may need more work.
After excavation, grade the yard so water runs away from the house, the pool, and any low corners where puddles would collect. Lay a weed barrier (usually landscape fabric) over the bare soil if weeds are a concern, but remember that the barrier does not stop water drainage, only root penetration. Next, spread a free-draining base material, typically decomposed granite (DG) or crushed base rock, and compact it firmly in lifts of 1 to 2 inches using a plate compactor. Compaction is not optional: an uncompacted base will settle under foot traffic, creating dips and soft spots where water pools and odor builds up. Once the base is compacted and level, you may add an optional draining underlay or pad if you want extra cushion for pets or play, or if you are installing turf over concrete or a patio. Finally, the turf is laid, seamed, and infilled.
On hard surfaces such as concrete, balconies, or travertine pool decks, never glue turf flat to the slab. Instead, lay a draining underlay or pad first, ensure the edges drain freely, and allow water to run off the sides or through the pad. Turf bonded to a slab that holds water will trap moisture, rot the backing, and smell.
Base Prep on San Diego Caliche: Excavation, Base Rock and Compaction
San Diego's native soil is hard, compacted desert caliche, a layer of calcium carbonate and clay that sheds water rather than absorbing it. Caliche drains poorly, stays wet after rain, and is too hard to compact turf directly onto it. This is why base preparation is non-negotiable in San Diego yards. Excavation breaks up the caliche and removes the top layer of native soil, creating room for a free-draining base that keeps water moving through the system instead of pooling underneath.
Once you have removed the old lawn and roots, excavate down to 3 to 4 inches (or deeper if grading requires it), breaking up caliche as you go. Grade the excavated area with a fall away from the house, the pool, and low corners, aiming for at least a 1 to 2 percent slope so water does not pond. Then spread decomposed granite or crushed base rock in lifts of 1 to 2 inches and compact each lift firmly with a plate compactor. The compaction step is critical: a loose, uncompacted base will settle under foot traffic within weeks, creating dips where water collects and odor festers. Proper compaction also prevents the turf from shifting or wrinkling over time. After the base is compacted and level, you are ready for the optional underlay and then the turf itself.
If your yard has a genuine drainage problem, a history of standing water, or a location where groundwater is close to the surface, drainage must be addressed before turf is installed. Surface grading alone may not be enough. In those cases, we work with the property owner to evaluate the situation and recommend solutions, or we decline the job rather than install turf that will fail. A low-maintenance turf installation assumes the ground beneath it drains reasonably well.
Artificial Grass Drainage and Underlay: Perforated vs Fully Permeable
Artificial grass itself drains through the backing and the infill, but the rate of drainage depends on the backing type. Turf backings come in two main categories: perforated backings, which have small holes punched through them, and fully permeable backings, which allow water to flow through the entire surface. Fully permeable backings drain faster, typically 20 to 30 gallons per hour per square foot or more, while perforated backings may drain at 5 to 15 gallons per hour per square foot. The faster the drainage rate, the better the turf performs in heavy rain, in pet areas where urine needs to flush through, and in high-traffic zones where moisture builds up.
However, a fast-draining turf is only as good as the base beneath it. If the base is uncompacted, holds water, or sits on caliche that sheds rain, the turf will fail. Water will pool under the turf, the infill will stay wet, odor will develop, and the backing will eventually rot. This is why base preparation and drainage go hand in hand. We specify the turf backing and drainage rate based on your use case, and we build the base to match. For pet turf, we choose a fast-draining backing and a compacted base that sheds water quickly. For pool surrounds and patios and balconies, we add a draining underlay or pad to handle water and provide a softer feel.
Ask your installer for the drainage rate of the turf backing in gallons per hour per square foot, and ask how the base is designed to drain. If the answer is vague or the base is not compacted, that is a sign of a shortcut installation. A real turf installer will explain both the turf and the ground, because they work together.
Seams, Nails, Edging and Power Brooming
The finishing work separates a professional installation from a DIY or rushed job. Seams are the joints where two pieces of turf meet. A proper seam is joined with seam tape and a polyurethane or latex adhesive, with the pile grain aligned so the fibres run the same direction on both sides. The adhesive sets over 24 to 48 hours, and a good seam is nearly invisible once it cures. A visible seam, a seam that lifts at the edges, or a seam where the grain does not match is a sign of poor workmanship. Seams can also fail if the base underneath is not firm, if the turf was not power broomed after installation, or if the adhesive was applied incorrectly.
Around the perimeter, the turf must be secured and edged cleanly. Nails or staples are driven through the turf into the base at the correct spacing (typically every 6 to 12 inches, depending on the turf weight and the conditions). The edges are finished with bender board, metal edging, or a secured perimeter that keeps the turf from rolling or peeling. On patios and pool decks, the turf is cut tight to pavers or cool deck material so water drains freely and the edge does not trap debris. Power brooming is the final step: a mechanical brush is run over the entire surface to stand the fibres up, spread the infill evenly, and give the turf a natural, finished appearance. Without power brooming, the turf looks flat and the infill is unevenly distributed.
When you inspect a finished installation, look for seams that are tight and grain-matched, edges that are clean and secured, and a surface that is uniformly fluffy and level. If you see lifted seams, gaps, loose edges, or flat, matted fibres, ask your installer to repair the work before you pay the final bill.
What a Written Turf Spec Should Include
Before any work begins, you should receive a written specification that names every material, measurement, and method your installer will use. This is your protection and your reference. A proper written spec includes the turf product name and fibre type (polyethylene, polypropylene, nylon), the face weight in ounces per square yard, the pile height in millimeters, the backing type and drainage rate in gallons per hour per square foot, the infill type and amount in pounds per square foot, the base material and depth (for example, 3.5 inches of compacted crushed base rock), the weed barrier (if any), the seam method (seam tape and adhesive), the edging treatment, cleanup and haul-off, and the workmanship warranty period (typically one to three years on the installation itself).
The spec should also include the square footage of the project (measured on site, not estimated), the location of seams, any special conditions (such as slopes, hard surfaces, or drainage concerns), and the timeline. Do not accept vague language such as "quality base" or "premium infill" without specifics. Ask for the turf face weight, pile height, backing type, infill pounds per square foot, and base depth in writing. This is not excessive; it is standard practice for any professional turf installer. If an installer resists putting details in writing, that is a warning sign.
Once the work is complete, ask for a copy of the specification with a note that the work was performed as specified. This record helps if you ever need repairs or if you are selling the home and want to document what was installed. For a free on-site estimate and written spec, contact us at (619) 831-6744. See our pricing page for typical ranges and what to expect.