Laying patio slabs without a gravel bed as a substructure saves time and money. In order for the project to succeed, important prerequisites must be observed. Here you can find out how to lay slabs for the terrace directly on the ground.
In a nutshell
- Laying slabs directly on earth always requires a 2% slope
- Before laying, compact the soil with a vibrating plate or hand tamper
- A thin layer of sand of 5-10 cm between the ground and the slabs optimizes stability
create gradient
The fundamental prerequisite for permanently laying patio tiles directly on the ground is a slight incline to protect against waterlogging. Because there is no substructure made of gravel and crushed stone for drainage, the rainwater should be given an alternative way of draining off quickly. This measure can be included in the preparatory work. How to do it right:
- Mark the terrace area with stretched mason's cord
- Dig out the marked area, matched to the height of the panels (flush with the floor)
- Create a gradient of at least 2%
- Important: slope leads away from the house
In order to set the desired slope, stretch masonry cords at the level of the finished upper edge of the terrace. Align the cords exactly horizontally using a spirit level. After the first meter of terrace width, mark 2 centimeters below the masonry cord with adhesive tape. Repeat this step at intervals of one meter to the end of the terrace area. Finally, move the cord to the height of the markings - the even gradient of 2 percent is done.
Tip: A 5 to 10 centimeter thick layer of sand between the ground and the terrace slabs effectively prevents wobbly stone tiles. Simply dig the terrace surface deeper, spread sand, smooth and shake firmly. Crushed sand is perfectly suited to prevent ants from undermining the area.
compact earth
Not using a bed of gravel or crushed stone as a substructure carries the risk of terrace slabs sagging within a short time after they have been laid. You will be spared this hassle if you compact the soil. Ideally, you should use a vibrating plate for this. You can rent this useful device cheaply in many hardware stores or from machine rental companies. Bargain foxes in good physical condition compact the soil with a hand tamper.
If you opt for the economy variant with hand tamper and muscle wax, all disturbing objects must be removed from the excavated area manually in advance, which a vibrating plate would simply pound into the ground. Then divide the soil area to be compacted into meaningful sections. Put on work gloves to protect against calluses and blisters. Step by step, tamp the ground seamlessly and level. You can then lay the terrace slabs directly on the prepared soil.
Tip: Use a rubber mallet to tap each patio tile into place. In this way, small cavities, which can arise when laying directly on the ground, are closed. The effort is worth it, because stone slabs that have been knocked down lie better and don't wobble.
frequently asked Questions
Can you do without expansion joints?No, minimal expansion joints of 2 millimeters are strongly recommended for direct laying on the ground. Expansion joints buffer earth movements that would otherwise cause cracks and fissures in the valuable stone tiles. With practical spacers, you can easily keep the distances between the terrace tiles. Finally, remove the spacer crosses and sweep up the joint sand.
Is the terrace immediately accessible?The laying of patio tiles directly on the ground is always associated with a settlement phase. Be patient for a week or two before you set foot on your new terrace or inaugurate it with a happy party. Until then, it is advisable to mark the area with warning tape.
Which patio tiles are suitable?A board thickness of at least 2 centimeters is the most important prerequisite for laying outdoors without a substructure. Furthermore, terrace tiles should be weatherproof, chemical-resistant and frost-proof. The Italian manufacturer Refin is a pioneer in this field with its innovative product line OUT 2.0 for terraces, gardens, paths and courtyards.