How to Install a Shock Pad Under Artificial Turf: Step by Step

Installing the pad is the part of the build you cannot inspect afterwards — once the turf and infill are down, a mistake in the pad layer is invisible until the surface starts to dip, hold water, or come apart at the joints. This guide covers the sequence, the checks that matter at each step, and the mistakes that are expensive to discover late.

Before you start: what the sub-base has to be

The pad cannot fix a bad sub-base. It can only sit on a good one. Whatever your base is, four things must be true before the first sheet goes down:

Firm. No soft spots, no loose material that will settle unevenly under load. Walk the area and feel for movement.
Even. Within the tolerance your system designer specified. Pads follow the base — they do not level it. A 10 mm dip in the base becomes a 10 mm dip in the finished pitch.
Drained. Water must be able to leave the assembly. Through the pad, into the base, and out.
Clean and blunt. No sharp stones, no protruding fixings, no construction debris. Anything hard and pointed will print through the pad over time.

Three base types cover most installations:

Sub-base	Typical of	What to watch
Compacted aggregate	Most landscaping and sports installations	Compaction consistency across the whole area; water must pass through the layer, not sit on it
Concrete / asphalt	Rooftops, podiums, balconies, retrofits	Drainage has to come from the pad and the outlets you provide — the base cannot absorb anything
Existing hard surface	Upgrades where an old surface is reused	Clean off old infill and debris; check the surface is sound, not crumbling

On falls: artificial surfaces are normally laid to a fall that moves water away from buildings and toward outlets. The exact figure is a design decision — confirm it with your designer or the project specification rather than assuming. What matters here is that you check it before laying, while you can still correct it.

If your base cannot accept water quickly — a concrete deck, a roof membrane, heavy clay — then lateral drainage becomes the governing design case, and the pad's drainage geometry is doing the work. Plan the outlets before you plan the layout.

Tools and materials

Tape measure, string line or chalk line
Long straight edge and a spirit level
Utility knife with hook blades (spare blades — foam dulls them quickly)
Straightedge or board to cut against
Rubber mallet (for engaging interlocks, never metal)
Gloves and knee protection
Geotextile or separation layer, if the specification calls for one
Turf nails, pegs or edge restraint as required by the system
A length of timber to spread load when kneeling on freshly laid pad in hot weather

The installation sequence

Step 1 — Re-verify the sub-base

Do not skip this because it was signed off two days ago. Walk the whole area, straight-edge it, and confirm drainage actually works by running water on it if you can. Every hour spent here is worth several spent later. Photograph the base before you cover it — it is your only record of what is underneath, and it protects you if a dispute arises later.

Step 2 — Set out your first line

Choose the line the installation will be judged from — usually the longest visible edge, or the sight line from the main viewing position. Strike a string on it and get the first row square to it. If the first row is out, the error accumulates across every subsequent row and shows up worst at the far edge.

Step 3 — Lay the first row

Lay the first sheet into position without dragging it across the base — dragging picks up grit and can round the interlock profile. Set it down, then nudge it into final position. Leave the perimeter oversail: the pad should run slightly past the finished edge and be trimmed after the surface is set, not before.

Step 4 — Engage the interlock properly

Interlocking edges are designed to transfer load between sheets. An engaged joint does that; a joint that is nearly engaged does not, and it fails progressively.

Align the profile along its whole length before applying any pressure — do not start at one end and force it along.
Tap along the joint with a rubber mallet to seat it fully. Work from the middle outward.
Check with your hand or a straight edge that the two sheets are flush. A lip that is obvious now becomes a wear line in the turf later.
Never force a joint with a metal hammer or by standing on the edge — you will deform the profile and the joint will never seat correctly.

Step 5 — Work across the area, staggering the joints

Offset the joints between rows the way brickwork is staggered, rather than letting them line up from one end of the pitch to the other. Continuous aligned joints create a long straight line of weakness; staggered joints distribute it.

In warm weather, lay in the cooler part of the day where you can, and avoid kneeling on freshly laid pad with all your weight on one knee — use a board to spread the load. Foam that is compressed while warm can take a set.

Step 6 — Cut in around edges and penetrations

Cut with a sharp hook blade against a straightedge, in more than one pass for thicker pads rather than forcing a single deep cut. Cut slightly inside your finished line and trim in stages — it is much easier to take a little more off than to add material back.

Around drains, posts, goal sockets and inspection chambers, cut a neat aperture and keep the surrounding sheets fully supported. A sheet that is unsupported around an opening will flex every time someone steps near it.

Step 7 — Check the surface before you cover it

Before any turf goes down, walk the whole pad area barefoot or in soft shoes and check for:

Proud edges or lips at the joints
Sheets that rock or move when stepped on
High or low spots — straight-edge the area in several directions
Any area where water would obviously stand
Debris, offcuts, fasteners left on the surface

This is the last moment at which these are cheap to fix. Fix them now.

Step 8 — Install the turf above it

Once the pad is down and checked, the turf goes on top following the turf manufacturer's own installation method — including infill type and depth where specified. Two points that concern the pad layer:

Do not let the turf installation load the pad unevenly. Heavy infill bags dropped in one spot on a foam pad can leave a depression that never fully recovers.
Respect the system you specified. If your compliance or performance claim depends on a tested assembly of turf, infill and pad, substituting any one of them invalidates the claim. Install what was tested.

The mistakes that cost the most

Using the pad to level an uneven base. It cannot. Any dip stays a dip.
Skipping the drainage check before laying. You cannot test drainage properly once the pad and turf are down.
Half-seated interlocks. The most common defect, and the one most likely to be blamed on the material. Check every joint.
Aligned joints running the length of the area. Creates a continuous weak line across the whole surface.
Dragging sheets into position. Grit under the sheet and a damaged profile.
Cutting with a blunt blade. Tears rather than cuts, and leaves a ragged edge that lifts.
Leaving the pad exposed to direct sun for days before the turf arrives. UV exposure is not what these pads are designed for; sequence the deliveries so the exposure window is short.
Not photographing the base. When a question comes up in two years, you will want the record.

After installation: what to check

Walk the full area and listen — hollow or rattling spots usually mean a joint that never seated.
Check the perimeter and every penetration for a lip or unsupported edge.
Confirm water still reaches the outlets in the places you expect.
Record the date, the batch and the installation layout, so future repairs can match the material.

Frequently asked questions

Not as a finished base. The pad needs a firm, stable, drained base underneath, normally compacted aggregate designed for the purpose. Laying on loose soil or sand means the pad moves with the base and the joints open up.

Interlocking profiles are designed to be mechanically engaged without adhesive, which is what makes them fast to lay and easy to lift for repairs. Follow your system specification — if it calls for tape or adhesive at the joints or at the perimeter, use it. Do not add adhesive to a joint that is designed to be dry-fitted and expect it to behave as tested.

Allow for the perimeter trim plus any penetrations, and add a margin for cutting errors. The figure depends on how complex your outline is — a simple rectangle wastes very little, an irregular boundary with many penetrations wastes considerably more. Ask your supplier for the coverage per sheet and work from effective coverage, not overall sheet size.

Yes, and it is a common application — but here drainage has to be managed entirely by the pad and the outlets, because the deck beneath will not absorb water. Plan the rainwater path and the outlets before laying, and check the loading of the deck with the structural designer.

Keep the exposure window short. These pads are designed to sit under turf, not to be a finished surface in direct sun. Sequence the delivery so the pad is laid shortly before the turf, and protect it from site traffic and from being used as a working platform in the meantime.

Testing drainage on the finished base before laying, and walking the finished pad before covering it. Both take minutes and both are impossible to do properly afterwards.

A note on our own data

This guide describes good practice in the sequence; it is not a substitute for your project specification or your system designer's instructions. Where a project requires compliance with EN 1177, ASTM F1292, EN 15330-4 or FIFA, the installation must follow the tested configuration exactly — and we will tell you plainly what we can and cannot currently provide rather than imply a certification we do not have.

Our EcoDrain range is produced in 20 mm, 30 mm and 40 mm from 100% recycled XPE, in interlocking sheets of 2290 × 940 mm overall (2250 × 900 mm effective). See the full specification →