Laying slabs of concrete or natural stone in the garden is not an easy and, above all, a heavy undertaking. While concrete slabs can still be brought in quite easily, laying natural stone slabs is a lot more demanding. Not only is the material often much more expensive, the processing and professional assembly also require a certain degree of sensitivity and knowledge of the material.

When laying garden slabs, precision is required

Slab coverings always require a slope

Slab coverings always need a gradient so that excess surface water can drain off. If laying on sand and grit (€46.95) with permeable joints, a gradient of two percent is sufficient, while sealed surfaces require a gradient of a good three percent. Route the slope so that it runs away from buildings and drains into a planting or lawn area. This not only saves you expensive drainage systems, but also ensures that the vegetable garden is properly irrigated.

Create a suitable substructure for garden slabs

The larger the individual slabs are, the more secure they have to be and the more important it is to have a substructure that is frost-proof and absolutely solid and level when building the surface. For natural stone slabs that are sensitive to breakage, it is even advisable to build a concrete foundation. This guarantees that the (always frost-resistant!) panels will not break, even over the course of many years. There are two different ways to create a substructure: waterproof and waterproof. The latter is a concrete foundation that rests on compacted gravel or anti-freeze gravel.

Build a water-permeable foundation:

  • Unpack the area to be covered at least 50 (preferably 60 or more) centimeters deep.
  • Then there is a layer of gravel or antifreeze gravel about 30 centimeters thick.
  • This is compacted with a vibrating plate (€499.00).
  • At least ten centimeters of sand or grit are then added.
  • This layer is also thoroughly shaken.

For the waterproof substructure, fill in a layer of concrete instead of sand or grit. The panels are glued to the still wet concrete, which is why you should not apply the layer all at once, but in several work steps. Otherwise you would have to hurry too much with the application, alignment and gluing of the panels.

Laying concrete slabs - Here's how

A water-permeable substructure is usually sufficient for concrete slabs, so that the slabs can be laid on sand or grit. Always measure the slabs with a straight edge and level them with a mason's trowel or small shovel if necessary. Finally, tap them into place with a rubber mallet. If you lay on sand, you should moisten it a little before laying: This way it can no longer settle after laying. Depending on the type of panel, leave joints of four to seven millimeters and only then connect the next panel.

Grout concrete slabs

Now sweep fine quartz sand (€15.85) into the joints, where it wedges and provides strength. Leave excess sand on the surface for a few days and then sweep it into any joints where the sand has settled a bit.

Laying natural stone slabs - you should pay particular attention to this

Natural stone slabs (e.g. granite, sandstone or basalt) are basically laid as described for the concrete slabs, but do not use quartz sand for grouting, but with a special adhesive for natural stone slabs. You can make final corrections using a rubber mallet. After laying, clean the panels with a wet sponge. Never place panels close together without a joint so that they have room to move when there are major temperature fluctuations. Always work from the inside out and try not to leave gaps that are too big. However, larger gaps can also be filled with pebbles, small stones or soil, in which you can settle moss or other small ground cover.

tips

To prevent the panels from tipping over at the edges, the substructure should be placed slightly beyond the panel surface. You can then fill in soil for a lawn or a planting area.

Category:

Garden design