A new artificial lawn can look flawless on delivery day and still fail within a season. The grass was never the problem; the work underneath it was. We have walked handovers where a flat-looking surface hid a base that turned to sponge after the first heavy rain.
How to tell if artificial grass is installed correctly is less about eyeballing the grass and more about checking the things you cannot see once furniture and feet arrive. The handover checklist below gives contractors, landscape designers, and project buyers pass criteria for each item, and shows what a failed item actually looks like.
What a Proper Handover Inspection Actually Checks
Most online checklists were written for a homeowner peering at their own backyard. A contractor or project buyer needs something tighter at handover: a signed list of acceptance items, each with a pass criterion and a known failure signal. This is that list.
How to tell if artificial grass is installed correctly starts by separating the six acceptance axes. They are the base (flatness and slope), the seams, color consistency, edge fixing, drainage, and infill with pile direction. Each axis below carries its own pass line and its own failure signal.
| Acceptance item | Pass criterion | Failure signal |
|---|---|---|
| Base flatness and slope | Straightedge shows no gap; 1–2% fall to drain | Visible gap, reverse or flat grade |
| Seams | Near-invisible, same pile direction | Dark line, step, or ridge |
| Color consistency | Even field, one dye lot | Patchwork or hard color line |
| Edge fixing | Held down, will not lift | Curl, flap, or trip edge |
| Drainage | Hose test clears within minutes | Standing water in low spots |
| Infill and pile direction | Seated at base, one direction | Flat blades, light split |
| Hardscape transition | Flush cut, backing hidden | Ragged fringe, gap over 5 mm |
Walk the surface with the installer on handover day, then re-check after the first rain. A dry, empty lawn hides more than it reveals, and the items in the table are exactly where rushed jobs betray themselves later.
Flatness and Slope: The Base Below the Surface
The base is the part nobody sees, which is exactly why it gets rushed. Run a long straightedge across the surface in several directions. A correct install shows no visible gap between the board and the turf anywhere on the lawn.
On a rooftop terrace we reviewed, the base fell the wrong way and pushed every storm toward the waterproof membrane edge. A 1–2% fall toward the drainage side is the line a correct install holds; a reverse or flat grade fails the moment water arrives.
Feel the whole surface with your foot. It should read firm and even, with no soft spots and no sinking under weight. The base beneath should sit three to four inches deep and be compacted to roughly 85–95%.
Flatness and slope are the first items on how to tell if artificial grass is installed correctly because they decide whether the lawn drains and stays put. Miss them and every later step works on a moving floor.
Inspecting the Seams Where Rolls Meet
Crouch at the seam and look along it from knee height. A correct seam is nearly invisible: no step, no ridge, no dark line where two rolls meet. Run your hand across; it should feel like one continuous surface.
Both rolls must run the same pile direction, or the join shows a light or color shift in raking light. The joining tape sits centered under the cut edges, the adhesive is spread evenly, and no blade tips are trapped in the glue during curing.
For large open areas, specify the 5 m roll width from our range of 2 m, 4 m, and 5 m by 25 m. Fewer rolls means fewer seams to insp