20 mm porcelain pavers can be laid in four main ways: on raised pedestals, dry on gravel or sand, as stepping stones in grass, or bonded to a concrete base with adhesive. The choice depends on what the area is used for and what is underneath.
Each method has its own rules, and the factory's own laying guidance should come first. This article gives you the overview you need to brief your customers and installers.
Pedestals
On pedestals, each corner of the paver sits on an adjustable plastic support. The pavers float above a roof membrane or a concrete slab. Water drains through the joints and runs away underneath.
This suits roof terraces, balconies over rooms and areas with services below. The surface is level even when the base slopes, and pavers can be lifted for maintenance. It is for pedestrian use only.
- Use only a paver and size the factory approves for pedestal use.
- Follow the pedestal maker's spacing and use support heads with tabs that set the joint width.
- Some large formats need a mesh or reinforcement on the back for pedestal use; ask the factory.
- Check wind uplift rules for high roofs, where pavers may need to be fixed or weighted.
Dry-lay on gravel or sand
The pavers sit on a compacted sub-base with a levelling layer of fine gravel or sand. No adhesive is used. Joints are left open or filled with sand or gravel, so water drains through.
This is quick and the pavers can be lifted and relaid. It suits gardens, patios and paths. The sub-base must be well compacted, or the pavers will rock and settle. Small, regular formats are easier to lay this way than large ones.
Stepping stones in grass
Single pavers are set into the lawn on a small bed of sand or gravel, flush with the soil. This is the simplest method and needs no frame. The base under each paver should be firm enough that it does not tip when stepped on near the edge.
Bonded to concrete
For heavier use, pavers are bonded to a sound concrete slab laid to a fall. Use a cementitious adhesive for outdoor use, typically class C2 S1 under EN 12004, with full coverage and back-buttering. Joints are grouted, and movement joints are placed at the edges and across large areas.
This is the method for areas where vehicles may drive. Dry-lay and pedestal systems are generally not suitable for cars. For vehicle loads, see what load heavy-duty parking tiles can take.
Choosing the method
- Roof terrace over a membrane: pedestals.
- Garden patio or path on soil: dry-lay on gravel or sand.
- Path across a lawn: stepping stones.
- Driveway or area with occasional vehicles: bonded to reinforced concrete.
- Pool surround or public space: bonded, with movement joints and the slip rating the rules require.
Our article on 20 mm outdoor porcelain pavers covers sizes and specification. For customer handouts, include the factory's laying guide with each order.
Next step
We source pavers suited to the methods your customers use and collect the factory's laying guidance with each order. To plan an outdoor range, book a free sourcing review.