Artificial grass looks finished and green, but what matters most to its performance and longevity happens where you cannot see it: the infill that props up the fibres, the base that holds water or lets it drain away, and the preparation work that keeps the turf from settling, rippling or holding odor. This guide walks a Twin Falls homeowner through the materials, depths and techniques that separate a turf installation that lasts from one that fails within a season or two. Whether you are converting a lawn that has died in the August heat, building a dog area that will not turn to mud, or preparing a yard for an event or a move, understanding what goes under and around your turf helps you ask the right questions and verify the work before it is finished.
The high desert climate and silt loam soils of the Magic Valley bring particular challenges: winter freeze and thaw, summer heat, wind and the basalt bedrock that lies beneath many yards. A turf installation that works here is built on a plan specific to your site, not a one-size-fits-all shortcut. This guide covers infill types and amounts, base preparation and compaction, drainage design, finishing details and the written specification that protects you. When you are ready to move forward, call Twin Falls Artificial Grass Installation at (208) 595-5012 for a free on-site measurement and estimate.
Turf Infill Options: Silica, Coated Sand, Zeolite and Envirofill
Infill is the loose material that sits on top of and between the turf fibres. It serves as ballast to hold the turf in place, protects the backing from UV damage, adds weight for stability, and helps water drain through the system. The most common infill is silica sand, a natural mineral that is inexpensive and widely available. Silica sand is angular and dense, which makes it effective at supporting the turf, but it can compact over time and does not offer any special benefit for odor or temperature control.
Coated sand is silica sand that has been rounded and often coloured to match the turf blade or to reduce glare. The rounded particles compress less than sharp sand, they feel softer underfoot (a benefit in play areas and pet zones), and they can be tinted to improve the appearance of the turf in bright sunlight. Zeolite is a porous mineral that absorbs and holds moisture, which helps it trap ammonia and other odors before they escape into the air. Zeolite is often used in Pet Turf and Dog Run Installation and in yards with dogs or other pets. Antimicrobial and cooling coated infills, such as Envirofill, are engineered to reduce bacterial growth and lower the surface temperature of the turf in hot sun. These products cost more than basic sand but can make a real difference in pet areas and in yards where the turf will receive heavy use or direct afternoon sun. Crumb rubber (recycled tire material) is used in sports fields and athletic courts because it provides cushioning and impact absorption, but it is not commonly used in residential yards and is not recommended for pet areas or high-traffic family spaces.
How Much Infill Artificial Grass Needs, and Why
Infill is specified in pounds per square foot, and the amount matters. A typical residential turf product might call for eight to twelve pounds per square foot, while a heavy-duty or sports turf might require twelve to sixteen pounds or more. The infill props up the fibres so they stand upright and look full, protects the backing from UV rays that can degrade it over time, adds weight so wind and foot traffic do not shift the turf, and helps the drainage system work evenly across the surface. Too little infill is a common shortcut in cheap installations: the turf looks thin and flat, the fibres mat down quickly, and the backing is exposed to sun damage.
The exact amount your yard needs depends on the turf product you choose, the pile height, the face weight and the intended use. A putting green infill specification is different from that of a residential lawn, and a pet turf installation may call for more infill than a decorative patio surround. When you receive a bid or a quote, ask for the infill amount in pounds per square foot in writing, along with the type (silica, coated sand, zeolite or other). If a contractor cannot or will not state this number, that is a sign to ask more questions or look elsewhere. Infill is not a hidden detail: it is part of the specification that defines the quality and performance of your installation.
What to Put Under Artificial Grass for Drainage
The path to a well-draining, long-lasting artificial grass installation starts with what you remove and what you build underneath. If you have an existing lawn, it must be excavated and removed, along with the roots and thatch. If old artificial turf is already in place, it and its base are stripped away. Once the site is cleared to bare soil, you have a chance to grade it properly and build a foundation that will support the new turf and handle water the way your yard needs it to.
The next step is to lay a weed barrier (a landscape fabric that blocks weeds but lets water through) over the excavated soil. This prevents weeds from growing up through the turf and saves you maintenance headaches later. On top of the weed barrier goes a free-draining base layer of decomposed granite or crushed base rock, typically three to four inches deep, which is then compacted firmly with a plate compactor to create a stable, level platform. For pet turf and dog runs, playgrounds, and patio and pool areas, an optional draining underlay or foam pad is installed over the base rock before the turf is laid. This pad adds cushioning, improves drainage in heavy-use areas and helps prevent odor from pooling. On concrete, balconies or other hard surfaces, a draining underlay is essential, and the turf is never glued flat to the slab. Water must be able to move away from the surface and edges, or it will pool, trap odor and degrade the backing. The turf is then unrolled, cut to fit, and seamed and fastened according to plan.
Base Prep on Twin Falls Soil: Excavation, Base Rock and Compaction
Twin Falls sits on deep silt loam soils over lava rock, with the Snake River Canyon just north and the high desert plain opening to the south. The soil here is fine and can hold water, especially in spring and early summer when snow melt and irrigation runoff move through the ground. If your yard has poor natural drainage, or if the existing lawn has been thin and patchy, or if you have noticed puddles after rain or snow melt, the base preparation is where the problem is solved. Base prep begins with excavation to remove the existing lawn, roots and any old turf or debris. The depth of excavation depends on what is underneath and what you are building, but typically the soil is dug out to a depth where you can install three to four inches of compacted base material and still have the finished turf at the right height relative to walkways, patios and the house.
Once excavated, the site is graded so water runs away from the house and away from pools, patios and other structures. A plate compactor is then used to compress the base rock or decomposed granite in lifts (layers), typically two inches at a time, until the base is firm and stable. Proper compaction is critical: an uncompacted base will settle and shift under foot traffic and weather, causing the turf to dip and ripple, creating low spots where water pools and odor concentrates. If your yard has a significant water problem, such as a high water table, poor drainage to a low corner or standing water after heavy rain, that drainage issue must be addressed first. In some cases, this means grading, installing a French drain or other subsurface drainage, or redirecting water away from the problem area. If the drainage problem cannot be solved within the scope of turf installation, we will tell you so rather than install turf over a foundation that will fail.
Artificial Grass Drainage and Underlay: Perforated vs Fully Permeable
Artificial grass itself drains water, but the rate matters and depends on the backing. A turf with a perforated backing (small holes punched through) drains more slowly than one with a fully permeable backing (a porous material that lets water pass through freely). Drainage rate is specified in gallons per hour per square foot, and a typical residential turf might drain at four to eight gallons per hour per square foot, while a sports or play turf might drain at ten gallons per hour or more. The faster the drainage rate, the quicker water moves through the turf and into the base below, which is especially important in pet areas where urine sits on the surface and in yards that receive heavy rain or irrigation.
However, even a fast-draining turf will fail on a base that does not drain. If the base rock is compacted too hard, or if the underlying soil is clay or silt that does not let water through, the water will pool on top of the base and under the turf, creating soft spots, odor and a surface that feels spongy or unstable. For this reason, base preparation and drainage work together. In areas prone to heavy water (such as under downspouts or in low corners of the yard), an underlay or foam pad under the turf can help move water sideways to a drain point. On hard surfaces like concrete or a balcony, an underlay is essential to create a gap between the turf and the slab, and edge drainage (a slope or a drain channel) ensures water does not collect at the perimeter. When you ask a contractor about drainage, ask for the turf's drainage rate in writing, and ask how the base will be built to handle the water that comes through it.
Seams, Nails, Edging and Power Brooming
The finishing details of a turf installation reveal whether the work was done by someone who understands the craft or by a crew that simply unrolled turf and moved on. Seams are the joints where two pieces of turf are joined together. A proper seam is created by aligning the grain of the turf (the direction the fibres lay), overlapping the edges, cutting them to fit snugly, applying a seam tape and adhesive to the backing, and pressing the pieces together so the seam is tight and invisible. A visible seam, a seam that is raised or ridged, or a seam where the fibres do not align tells you the work was rushed or the installer did not have the skill to do it right. Nails or staples hold the turf around the perimeter, and they must be spaced correctly (typically every six to eight inches) and driven flush so they do not catch a foot or catch sunlight.
Edges are finished with bender board (a flexible edging material), a concrete or paver border, or another secured perimeter that holds the turf in place and looks clean. On a patio or pool deck, the turf is cut tight to the pavers or concrete, and a draining edge or a slope ensures water does not pool at the boundary. After the turf is laid and fastened, it is power broomed: a rotating brush is run over the surface to stand the fibres up, spread the infill evenly, and give the turf a full, finished appearance. A turf that has not been power broomed looks flat and matted, and the infill is clumpy and uneven. A lifted edge, a seam that has come open, or turf that is rippling or dipping are all signs that the base was not compacted properly, the turf was not fastened correctly, or the finishing work was skipped. When you inspect the work before signing off, look for tight seams, secure edges and a full, even surface.
What a Written Turf Spec Should Include
Before any work begins, you should have a written specification that describes exactly what will be installed. A good spec is not a contract or a legal document; it is a clear statement of what you are paying for, so there is no confusion and no surprises when the work is finished. The spec should include the turf product name and fibre type (polyethylene, nylon or polypropylene), the face weight (the weight of fibre per square yard), the pile height (the length of the blade), the backing type and its drainage rate in gallons per hour per square foot, the infill type and the amount in pounds per square foot, the base material and depth, and the degree of compaction (such as 95 percent Proctor density). It should also state the weed barrier, the seam method, the edging, cleanup and haul-off, and the workmanship warranty period.
A written spec protects you because it gives you a standard to measure the finished work against. If the installer says the turf will drain at eight gallons per hour per square foot and it drains at two, you have it in writing. If the base is supposed to be four inches of compacted rock and it looks thin and loose, you have the spec to point to. When you call for a free estimate, ask for the spec in writing before you commit. If a contractor resists or says it is not necessary, that is a warning sign. We provide a written spec for every job, and we fully insure our work. Visit our pricing page to understand how we approach cost, and call (208) 595-5012 to schedule your on-site measurement and spec.