What is a raised deck terrace?
A raised deck terrace is a system known for centuries that allows you to create a floor at the required height using pedestals (spacers). The pedestals separate the substrate from the usable surface. Such a system has many advantages, not only related to practicality or use, but also to installation time. In this system, we can use various finishing materials, e.g., ceramic, concrete, or stone pavers, wooden or composite boards. Terrace pavers or boards rest on adjustable pedestals or support pads of fixed height.
This creates a space between the substrate and the surface, which allows for:
- free water drainage,
- protection of the waterproofing,
- running installations under the terrace,
- easy maintenance and disassembly of individual elements.
How to plan the construction of a terrace?
When starting the installation of a terrace, you should have a vision and a project for it. This is important so that you don't have to think about the layout of the structure or the choice of the top covering during installation.
Before starting work, it is worth determining:
- the type of use of the terrace,
- the planned surface material,
- the target height of the structure,
- the expected loads (e.g., jacuzzi, heavy planters, pergola),
- the drainage method (slope directions)
Good practice is to create a simple sketch or project. This will help avoid problems during installation and accurately determine the amount of materials needed. It is very important to determine what material the usable surface will be made of.
After choosing the material you want to use for the flooring, you need to determine its total thickness (e.g., for a concrete paver, it will be just its thickness; for wooden boards, you also need to add the thickness of the joist). When determining the height of the terrace, it is best to base it on the height at which the terrace doors are located, specifically the threshold, so as not to create a step between the floor inside the house and outside.
How to build a terrace on grass or gravel?
Terraces built directly on the ground are among the most popular solutions in gardens.
Regardless of whether the surface of our ground is grass or soil, we must properly prepare the substrate for spreading gravel. The construction of the terrace should begin with removing the grass from the substrate.
Step 1. Remove the turf layer
If the substrate is a lawn, remove the turf to a depth of about 5–10 cm.
The depth of the removed soil depends on:
- the thickness of the pavers,
- the planned layer of gravel,
- the height of the support pads.
Step 2. Spread a layer of gravel
It is best to use two types of aggregate - coarser at the bottom and finer at the top, so that they fill the voids between the coarser elements.
Such a solution ensures not only good stabilization, but also easier leveling.
The gravel layer also effectively serves as drainage, as water is easily drained from it. The gravel between adjacent stones collects water, which over time soaks into the ground. It should be remembered that during heavy rainfall, a great deal of water accumulates.
The thicker the gravel layer, the greater the amount of water it can accumulate.
Step 3. Lay out support pads or pedestals
On the prepared base, you can lay both fixed-height support pads (the smallest being 2 mm) as well as adjustable pedestals.
The choice depends on the height that needs to be achieved as well as on the choice of material for finishing the terrace.
Step 4. Lay the terrace pavers
On the support pads you can lay:
- gres pavers (most commonly used 2 cm)
- concrete pavers,
- stone pavers.
The system does not require the use of adhesive or grout.
How to build a terrace on a concrete slab?
If you have an existing concrete slab, installation is even simpler.
Substrate Preparation
The concrete screed should be:
- stable,
- clean,
- free of loose elements,
- equipped with proper slopes.
Before starting work, sweep sand and dust off the terrace and clean it of any remaining adhesive and other dirt.
Additional waterproofing protection
If there is waterproofing on the surface, such as torch-on membrane, membrane, or thin waterproofing, it is recommended to use SBR rubber pads under each pedestal. Although the pedestals have no sharp edges, the pads additionally:
- protect the waterproofing,
- improve acoustics,
- reduce the transmission of vibrations.
Laying pavers
On the cleaned concrete slab, you can place pedestals or support pads, which should be spaced at distances corresponding to the lengths of the pavers.
It is best to start in a place where the final result will have as few small pavers as possible, i.e., pavers requiring cutting. The most common starting point for installation is the terrace entrance.
The pedestals are placed one by one under each individual tile, and you can immediately lay the chosen ceramic tiles on them without using adhesive. Marking a straight line with a string can make laying the tiles easier.
If, after laying the pavers on the prepared structure, it turns out that the pedestal heights need to be adjusted, this can be done without any problem—by turning the collar on the pedestal, you can adjust the paver surface even when tiles or boards with joists are already placed on it. Without having to remove them.
This is how we continue the installation, following all the rules for properly laying raised deck terraces. All generally applicable building regulations should also be observed.
Which pavers to choose for a terrace?
For a raised deck terrace, you can use both ceramic, concrete, or stone terrace pavers. It all depends on the intended use of the terrace. Some will be more fragile, while others will be much more resistant to external loads or minor impacts. When choosing, it is always worth considering what durability we need from the terrace.
Terrace pavers are chosen mainly for their visual appeal. However, their properties are equally important. A delicate material suited for balcony installation will not work on a driveway, etc.
The most commonly used on terraces are:
Gres pavers
They are characterized by:
- low water absorption,
- easy cleaning,
- a wide selection of patterns.
Concrete pavers
They are characterized by:
- high durability,
- attractive price,
- large thickness.
Stone pavers
They are characterized by:
- natural appearance,
- very high durability,
- resistance to weather conditions.
More information on choosing pavers can be found here:
See also: Laying pavers on a raised deck terrace - installation rules
Summary
A raised deck terrace can be successfully built on grass, gravel, soil, and a concrete screed.
When designing and installing a terrace, it is worth remembering:
- when choosing terrace paving tiles, it is worth selecting those resistant to frost, abrasion, and chemicals, preferably anti-slip
- when choosing porcelain tiles, you also need to pay attention to their resistance to fading and the need for maintenance,
- before starting work, have a ready plan for the tile layout that minimizes the number of cuts as much as possible
- all installations you want to hide should be placed under the terrace (you can cover them with gravel)
- the final appearance depends on the care taken during installation. Attention should be paid to proper leveling and alignment of the surface
- measure each paver with a spirit level in several directions to ensure it is laid evenly
- in the case of long continuous terrace surfaces, remember to maintain appropriate slopes
The most important thing is proper preparation of the substrate, maintaining the stability of the structure, and selecting the right pedestals or support pads.
Thanks to raised deck terrace technology, you can create a durable, aesthetic surface without using adhesives and grout, and complete the entire installation much faster than in traditional systems.
