Thickness or height of your terrace construction

by Staenis | 30/05/2022

Installing a driveway or terrace on the ground: which terrace structure to choose and which height to use?

Whether you want to build a terrace, a pavement on which cars will park, or a driveway. The terrace structure that you best provide is roughly the same. Discover the most suitable terrace structure for your project and learn how high or thick it will be. For a sustainable result, use the Staenis grid in combination with drainage mortar. A winning team for an extremely strong but draining screed. This allows you to enjoy your patio or driveway for an extra long time!

The secret of a terrace or driveway that stays beautiful for years

How thick or high your terrace structure should be depends on various factors: the desired bearing capacity, moisture drainage, rising damp and tensions. We recommend using a sub-foundation such as concrete rubble in any case. This prevents subsidence and makes the terrace structure load-bearing. By vibrating the concrete rubble with a vibrating plate machine, you compact and harden the soft surface.

A screed or screed is also needed for a strong driveway or a sturdy terrace. For a result that will last for years, install your screed using Staenisgrate, which you fill with drainage mortar or sand cement screed. With these combos, tensions in your floor disappear, and if you go for drainage mortar, your screed is also water-permeable.

  • The Staenis grid is a handy tool for laying your crack-free screed yourself. This screed grid consists of slats and height-adjustable legs, which you can easily click together and adjust in height with a screwdriver. The grid divides the floor structure into small fields of 0.25 m². Et voilà, a tension-free surface to tile on! As a result, there is no risk of cracking, collapsing and coming loose from the floor. Also, your driveway or terrace will not break due to freezing cold, warm weather or the scree silting up. So you are sure that your tiles will not crack. Discover the screed grid and learn more about how it works.

  • Thanks to the drainage mortar, moisture is always removed and your terrace floor will not freeze, silt up or expand, so that your driveway or terrace will last extra long. Draining mortar consists of (grave) porphyry 2-6 mm stones, mixed with cement. Calculate here how much drainage mortar you need for your job and order your drainage mortar silo via the Staenis webshop. With a silo on your site you can make fresh drainage mortar at your own pace and for a few weeks. Handy, because that way you can choose your own schedule.

Good to know: You can of course also use sand cement screed. Make sure to provide a draining substrate, so that the screed can always dry out or drip into the substrate.

Discover all the advantages of a draining terrace floor construction with Staenis grid.

How high should a floor structure for a driveway or terrace be?

The necessary height (thickness) of your terrace structure depends on various factors. Do you know how your driveway or terrace will be used, and how intensively? Check in the table below which load class the pavement must have. The load class is indicated in kiloNewtons (kN).

Classification of terraces according to their degree of mechanical stress.

To illustrate: If your terrace or driveway will be used by pedestrians and cyclists, you aim for load class 2. This corresponds to a minimum breaking load of 3.5 kN. For areas that are occasionally used by cars, light vehicles and/or motorcycles, the floor must again have a load class 3. This corresponds to a minimum breaking load of 6.0 kN.

Now check in the table below which thicknesses the layers of your terrace or driveway should have, and how high the total terrace structure will be.

Tip: Look at the type of surface on which your terrace will be built and then at the necessary class of load. The type of surface on which the terrace will be laid will have an impact on the thickness of the concrete rubble and drainage mortar layer.

Common thicknesses of the different layers of an outdoor terrace.

What does my ideal terrace structure on full ground look like?

Option 1: place your terrace or driveway with the Staenis grid

The terrace floor construction below with drainage mortar allow the moisture to drain off. In addition, your terrace or driveway will remain stress-free because you use the Staenis grid. This keeps the tile and grouting in top condition!

Terrace construction on full ground - terrace / driveway - ceramic tiles, natural stone and vowels

  1. Dig out the underground. When excavating the open ground, reserve 10 to 20 cm height for vibrated concrete rubble, 2 to 5 cm to level out the concrete rubble with drainage mortar (so that you can easily place the Staenis grid afterwards) and 7 to 8 cm height for the drainage mortar screed, tile adhesive and tiles or natural stone.

  2. Then place a drainage pipe that opens into the sump or drain. You place the tube in a slope so that the water can flow away.

  3. Then pour 10 to 20 cm of concrete rubble in several layers. You vibrate it again and again with a vibrating plate. This way you prevent your driveway or terrace from sinking later. The concrete rubble provides a pressure-resistant surface, but must be permeable to water.

    concrete rubble
  4. Lay a sloped filling layer of drainage mortar. This leaves 7 to 8 cm to adjust the height of the Staenis grid. Let this layer of drainage mortar dry for 1 day.

    Drainage mortar
  5. Place the Staenis grid. Determine the correct height of a leg with a laser every 3 m. Place a long line on it or use a rope. This way you can easily adjust the height of the intermediate legs with a screwdriver. Provide 1.5 to 2 cm slope per running meter (depending on the roughness/unflatness of the tile surface).

  6. Provide edge insulation around the screed so that it can expand and contract.

  7. Start by pouring the drainage mortar onto the legs. In this way the height control of the grid remains correct. Then fill in cubicle by cubicle with drainage mortar. Learn more about this step.

    Staenis grid
  8. Drag the drainage mortar flat with a large flat trowel (60 cm length) onto the grid.

  9. Create a small amount of screed. Use 5 parts washed sand plus 1 part cement. Mix it well and add a little water. Sprinkle the screed in a thin layer of about 5 mm on the drainage mortar (wet in wet). To reduce silting of the surface afterwards, it is best to use pre-made screed from bags (eg Knauf Chape or Weber Classic screed). It is stronger and mixed beforehand, so you get the same quality everywhere. This avoids sand stains and cement stains that arise because the screed mixture was not mixed well.

  10. Rub the screed flat with a large sanding board and polish the surface afterwards with a screed iron. This way you fill in the gaps and you are sure that the tiles will adhere well.


Good to know: you can also replace the drainage mortar with this floor construction with a sand cement screed.

Tips for building a terrace or driveway on the ground, using the Staenis grid

  1. Do you want to place a terrace structure on full ground for a terrace or driveway, finished with curbstone and ceramic tiles, natural stone or clinker bricks? Then you use the same method as above, with the difference that in step 1 you also have to place the curbstones in the stabilizer.

  2. Do you want to place a terrace construction with drainage gutter on the full ground for a terrace or driveway, finished with ceramic tiles, natural stone or clinker bricks? Even then you use the same method as with terrace construction 1, with the difference that in step 1 you also place the drainage gutter in the stabilizer.

Option 2: Placing your terrace or driveway in the classic way (without Staenis grid)

You can also build a terrace or driveway in the classic way, without Staenis grid. How do you handle that? Your tiles should be placed on a solid foundation so that they are stable and can withstand impact. You must make the necessary preparations for this, such as setting out the dimensions, excavating your plot, placing sub-foundations and edging. After the main foundation, place a geotextile, a reinforced screed and place the tiles.

  1. Setting out dimensions for your driveway or terrace: A first step when placing your driveway or terrace is demarcating the plot to be excavated.

  2. Excavation works for your driveway or patio: If you have marked where the top of your driveway or patio should be, calculate how deep you need to excavate the bottom.

  3. Installing a driveway or patio sub-foundation: The foundation under your ground cover prevents the ground from sinking over time under the weight of the cover and the pressure that will be exerted on it. For a driveway in tiles, you first pour a layer of stone rubble (20-25 cm thick). Then place root cloth with a layer of street sand of 5 to 7 cm. fat. Maintain a sufficient slope (1 cm per meter) so that the water can be drained quickly in case of rainfall.

  4. Placing a edging for your driveway or terrace: A edging prevents the tiles from sinking or shifting over time.

  5. Installing a foundation for a driveway or terrace: The foundation, together with a sub-foundation, provides a stable surface. The foundation layer for a driveway can consist of stabilized, sand or split. This depends on the pavement you are going to use.

  6. The screed or the sand or gravel bed is then placed on top of this, on which you then place finish, glue or apply with mortar. Good to know: For gluing tiles you use gray tile glue, for gluing natural stone you choose white tile glue.

  7. Placing and grouting tiles: Fill the seams between the tiles. This gives you one solid and beautiful whole.

Would you rather be sure of a sustainable result, without the risk of cracks and moisture problems? Then lay out your terrace or driveway using the Staenis grid, a handy DIY system. Learn how to get started here.

If you place your terrace or driveway using the Staenis grid, it will not suffer from tension and moisture. This way you avoid damage and you are assured of a long life. Moreover, you determine your own schedule. Find the ideal terrace structure for your project and watch the installation video. Calculate here what you need for your job and order your supplies in our webshop. Off you go!

Customer inquiries

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