Levelling and laying paving stones

Set and fix kerbs or an edge profile before the bedding layer is laid. The edge holds the paving in place and gives a firm stop to lay against. Kerbs are set in bedding mortar, plumb and in line (see the guide »Setting kerbs in concrete and mortar«).

Spread the screeding/bedding grit and screed it off with a screed board along two guide rails (e.g. pipes). The bedding layer is typically 30 ± 10 mm and at least 20 mm (DS 1136 / NfA practice). It is this layer that gives the paving its final fall — it must be completely even and at a constant fall.

Paving blocks and slabs must have at least 10 ‰ (1 cm/m) fall for drainage (NfA 1992); the industry recommendation for terraces is 15 ‰. Check the fall in at least two directions while you screed — it is far easier to correct in the bedding layer than in laid paving.

Stretch a line as a straight starting line along an edge or house wall, and lay the first row exactly to it. All subsequent rows follow this line — a crooked start carries through the whole area.

Lay the pavers in the chosen pattern and keep an even joint width of typically 2–5 mm (DS 1136, depending on paver format and project). Step on the pavers already laid, not on the screeded layer, so you do not leave impressions. Place the pavers down, do not push them — otherwise you push the grit ahead of you.

Cut paving to edges, gratings and manholes with a block splitter or angle grinder so the fittings are neat and free of chips. When cutting with an angle grinder: use an FFP2/P2 dust mask — stone dust from granite and concrete can contain quartz (Arbejdstilsynet); preferably cut with water cooling to bind the dust.

Avoid very small cuts at edges — they break and look poor. Plan the pattern.

Compact the paving with a plate compactor with a rubber plate/mat underneath, so the stones are not scratched. Vibrate from the edge inwards in overlapping passes. Hold off vibrating slabs that scratch easily — follow the supplier's instructions.

Fill the joints with washed, low-nutrient, kiln-dried quartz sand (0–4 mm) in accordance with DS 1136. The low nutrient content discourages weeds. Sweep the sand into the joints, vibrate again and refill until the joints are completely full — an empty joint invites weeds and lets the pavers move.

Sweep off excess jointing sand so no sand or haze is left on the pavers. Finally, check there are no dips: pour water on or look for standing water after rain. Puddles must be put right now — not at handover.