Terrace with flat concrete slab

Terrace 6 - Choose a different floor structure

flat concrete slab - terrace/driveway - with drainage gutter - ceramic tiles, natural stone and clinker bricks

Make sure that your terrace no longer breaks due to freezing, the weather being too hot or the screed silting up.

Information

Tension and moisture are the 2 biggest causes of damage to a terrace. This terrace floor construction with drainage mortar allows the moisture to drain off and is tension-free due to the Staenis grid, so that the tiles and grouting remain in top condition.

Benefits

Achieving a perfect end result without any experience
Replaces a drainage mat = savings of an average of 17 euros/m²
Replaces an uncoupling mat + glue = savings of an average of 20 euros/m²
Replaces the steel reinforcement mesh = savings of an average of 3 euros/m²
No expansion joints needed in the screed = savings of an average of 3 euros/linear metre
Floor construction avoids rising damp/capillary effect from the substrate
Water/moisture can quickly drain through the drainage mortar

No chance of the screed silting
Compartment of the screed = crack-free screed
No dishing/cupping of the screed = perfectly flat screed
Very load-bearing surface due to vibrated layers underneath
Spread floor works over several days (no stress during installation)
Very good adhesion to the tiles, by applying a fine layer of screed to the drainage mortar. Ideal for gluing tiles or natural stone

View all technical benefits

Floor construction manual

1. Place a sloping filling layer of drainage mortar or screed, leaving about 7 to 8 cm to adjust the height of the grid. This does not have to be reinforced and may start from 1 mm thick. When connecting to the ground, it is best to place a drainage pipe and fill it with 10 to 20 cm of concrete rubble. If necessary, ensure the gutter is placed in stabilised sand. 2. Place a waterproofing layer on the installed sloping filler layer. Use, for example, a kerdi cloth from Schlüter-systems, EPDM or roofing waterproofing. 3. Place the Staenis grid and determine the correct height of a leg every 3 m with a laser and 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 metre (depending on the roughness/unevenness of the tile surface). Place edge insulation around the screed to allow it to expand and contract. 4. Start by pouring the drainage mortar on to the legs. In this way the height control of the grid remains correct. Then completely fill in space by space with drainage mortar. Flatten the drainage mortar with a large flat trowel (60 cm length) on the grid. Prepare a small amount of screed and sprinkle it wet in wet as a thin layer on top of the drainage mortar. Polish with a large sanding board. This ensures that the remaining holes are filled and a good bonding strength to the tile is guaranteed. 5. Tip: the drainage mortar (in the Staenis grid) with this floor construction can also be replaced by a sand-cement screed topped with a glued draining tileable uncoupling mat of, for example, Schlüter Drain 8. 6. Tip: Place a foil over the freshly placed screed to prevent it from drying out too quickly and silting up. 7. Approved floor coverings: natural stone, ceramic tiles and stone clinkers. Always follow the installation instructions of both the floor covering manufacturer and the store where the purchase was made.

Terrace text manual Full manual Frequently Asked Questions Blogs about terraces

Side view floor construction

View this floor construction in reality via Sack Zelfbouw

Legend

open ground
Concrete rubble layers vibrated with vibrating plate
Drainage pipe connected to drain
concrete slab
Drainage gutter
Drainage mortar filling layer (fine gravel with cement)
Waterproofing (for example: Schlüter Kerdi)
Stainless steel grid (thickness of 7 to 8 cm)
Edge insulation
Drainage mortar (fine grave with cement) + 5 mm screed top layer
Double bonding with S1 flex tile adhesive (S2 not allowed)
Floor tiles
Water-resistant, coloured joint mortar
Silicone

Side view floor construction with screed

Legend

open ground
Concrete rubble layers vibrated with vibrating plate
Drainage pipe connected to drain
concrete slab
Drainage gutter
Screed with 250 kg/m³ cement
Waterproofing (for example: Schlüter Kerdi)
Stainless steel grid (thickness of 7 to 8 cm)
Vertical draining mat (Schlüter Drain 8) and edge insulation
Screed with 250 kg/m³ cement
Glued draining tileable uncoupling mat (Schlüter Drain 8)
Double bonding with S1 flex tile adhesive (S2 not allowed)
Floor tiles
Water-resistant, coloured joint mortar
Silicone

Installation Staenisgrid

More information about the thickness of the layers

Choose a different floor structure

Placement video

Placement of the Staenis grid

Installing drainage mortar for a terrace

We deliver drainage mortar and screed in a silo to your home (only in Belgium)

Screed and drainage mortar in silo delivered to home in Belgium

By simply pressing a button on the silo, you can prepare fresh drainage mortar or sand cement screed at a rate of 3 m³/h and this without time pressure to process the large amount of mortar.

There are 2 separate compartments in the silo. 1 part filled with porphyry (2-6mm) or sand (0/4-0/7mm) and the other part filled with dry cement (250kg/m³). These are only mixed with water when you wish.

The big advantage of this is that you can make fresh drainage mortar or sand cement screed at your own pace and for a few weeks.

Purchase drainage mortar in silo Purchase screed in silo

We deliver drainage mortar in bags to your home

Drainage mortar delivered to your home in bags

Cem Classic: drainage mortar, now conveniently packed in bags. This can be used/processed in the same way as the drainage mortar from a silo, but with the added advantage that it is three times lighter. This property greatly facilitates processing. Ideal for applying a water-permeable surface for small or difficult-to-reach terraces.

Purchase drainage mortar in bags

We deliver screed to your home in bags

Fast: Fast-drying, fiber-reinforced screed with only 2/3 of the weight compared to traditional screed. This makes the work considerably less difficult when you work with bagged material instead of traditional screed. Ideal for applying an adhesive screed screed floor or for small spaces, both indoors and outdoors. This Fast screed is easily spreadable, allowing you to achieve a flat finish more quickly.

Purchase screed in bags

Special joint sealant for joints with ceramic tiles

Special joint sealant for expansion and connection joints with ceramic tiles

Because this joint sealant looks just like a cement joint, the product can also be used as a replacement product for conventional joints.

Field of application when grouting 2 cm thick ceramic terrace tiles with 3 mm joint.

This grout is super flexible and sticks enormously to the side of the tile. Also, the grout does not discolor when moistened, which looks aesthetically pleasing.

Buy this tile grout silicone here