Laying paving slabs

The preparatory work is very important when lay paving slabs.

If it is wet where the paving slabs are to be laid you should dig deeper. You can fill with a draining macadam under the layer of base course. If you are careless with the preparatory work there is a risk of the paving slabs (due to ground frost) moving both horizontally and vertically. Chances that they will settle in the right position in the spring are very small.

You will need:

  • Wheelbarrow
  • Compactor/tamper
  • Rubber or wooden mallet
  • Spade
  • Broom
  • Rake
  • Straight edge
  • Screed rails
  • Water level
  • Folding rule
  • Brick line
  • Setting out pins

We recommend these materials:

  • Base course 0/32 or road gravel 0/16
  • Rock flour e.g. 0/2
  • Macadam e.g. 2/4
  • Geotextile fabric
  • Paving slabs

Do this

  1. Excavate the area where you intend to lay the paving slabs. The depth you need to excavate depends on the height of the paving slab. Estimate about 5–10 cm below the paving slab height. Coarse adjust the surface.
  2. Spread out base course. The base course should be about 5 cm thick. Compact this course with a tamper.
  3. Spread out the macadam. The macadam course should be about 5 cm thick. Level the surface with a rake.
  4. Position 2 screed rails along the slope of the bed. The rails are laid from the bed’s highest point to the lowest. You can use wooden battens 40x40 mm or iron pipe 32 mm in diameter. The length should be 2–3 meters. Press the rails into the material to the depth that gives the right height on the laid paving slabs.
  5. Make sure the screed rails are horizontal with the correct incline. Use the brick line so that the screed rail’s highest level is on the same level as the bottom of the paving slab.
  6. Take the straight edge (aluminum is lighter to work with than wood) and set it perpendicular to the screed rails and remove surplus macadam. The straight edge must be long enough to rest against the screed rails – at the same time as it reaches all the way out to the inner edges of the bed.
  7. Prior to laying the first paving slab, you should carefully remove the screed rails and fill the gap with macadam. Start by laying paving slabs on the lowest level of the surface if making e.g. a path, driveway or a patio that slopes slightly from the house foundation. You work from the bottom up – even if the slope is only small. Lay the paving slabs with an open joint of about 3 mm, all round. If you are uncertain you can place matches between the paving slabs.
  8. When you have laid the complete surface, you must fix the paving slabs using rock flour or joint sand. Cover the surface liberally with rock flour. Sweep the rock flour down in the paving slab joints. Run over the complete surface with a compactor and once again fill generously with rock flour, which is swept down between the joints.
  9. If you have a surface that does not border against a lawn for example you must allow this to be “supported”. Wearing course is suitable for this. Lay the wearing course against the paving slabs, compact and water to produce a hard surface and to avoid dust.