- The choice of stone for a terrace: reconstituted or natural
- A specific implementation
- The calepinage: an essential step
- 1 Installation of a gutter on the terrace
- Info +
- 2 Preparation and laying of slabs
- 3 Grouting the slabs of a terrace
Successful installation of an exterior cladding can not be improvised. Some rules of implementation are to be respected so that the terrace holds all its promises when the time comes! Explanations...
Cost: about 60 € / m2.
Time: 3 days
Equipment: mason ruler, meter, spirit level, pencil, trowel, sponge, mass, chisel, clamps, shovel, trough, wheelbarrow, hacksaw, drill, water grinder, bush-hammer, concrete mixer
Extending a tiled terrace with natural stone may seem simple. We choose a floor covering and we put it down. However, it must be ensured that this place of relaxation is in perfect harmony with the existing layout.
For this, several details are to be taken into consideration as the architecture, the materials of the house, the landscaping of the garden...
In other words, when the surface to be covered is important, there is no question of approaching the exercise lightly. The lack of taste does not forgive.
The choice of stone for a terrace: reconstituted or natural
Today, many manufacturers and distributors offer two types of products: reconstituted stone and natural stone. Both have many advantages (mechanical resistance, weather, UV...).
The main advantage of a reconstituted material is to imitate with talent the natural while giving it additional characteristics (anti-slip, non-gel...). But natural stone does not lack assets. As she gets older, she skates, changes her appearance, keeps her finesse... and proves durable. The main difference between the two materials is the price.
On average, reconstituted stone flooring costs € 30 / m2 against 50 € for natural stone.
A specific implementation
There are three types of laying for exterior paving: glued laying, sand bedding and sealed laying.
The glued laying consists in fixing the slabs with a mortar-adhesive (Weber, PRB, Parexlanko, Mapei...), applied on a few millimeters (variable according to the manufacturers). This technique does not allow the recovery of flatness contrary to the sealed installation (our example) which, thanks to the mixture cement, water and sand (Lafarge, Calcia, Vicat) authorizes thick layers (up to 8 cm) and especially the layout of a slope on large surfaces. As for laying on sand bed, it usually occurs in the absence of slab.
The calepinage: an essential step
In our example, the new terrace extends an older one, covered with tiles posed in opus incertinum (slabs of irregular shapes arranged freely). The choice was therefore naturally on a similar pavement, but with a variant: a pose in Roman opus (tiles of various sizes but regular shapes). The chosen model is a natural stone that can be found in several formats (20 x 20 cm, 20 x 40 cm, 40 x 40 cm and 40 x 60 cm). Its implementation must scrupulously respect the plan (calepinage) and the recommendations of the manufacturer.
1 Installation of a gutter on the terrace
The new terrace (in the extension of an older) requires the development of a few steps and a gutter (mortar bed pulled to the mason rule).
The trench is an opportunity to pass technical sleeves (for example, an electrical network as here), kept in the bottom of the search by mortar pads.
After preparing the mix in accordance with the dosages recommended by the manufacturer, the trench is filled with mortar, spread with a trowel. Then he is shot at the mason rule to be leveled (two wooden wedges make the operation easier).
The gutter is placed on the mortar bed.
The slab is ready. But before, some checks are required (spirit level and mason rule) to adjust the height of the gutter and respect the slope of flow.
In any outdoor development project (such as a terrace here), a minimum regulatory slope must be respected to facilitate the evacuation of rainwater to the gutters. It is imperative that this slope is 2% (2 cm / m) to be effi cient and ensure a good flow of water.
2 Preparation and laying of slabs
To determine the necessary mortar height, use shuttering boards, attached to each end of the slab.
To join the existing deck, take a control slab, then seal a wooden block that serves as a guide pad to check the thickness of the mortar.
Continue the placement of the studs respecting the length of the rule. These serve as a guide to pull the mortar and thus obtain the right thickness of screed.
Pour and level the mortar on the slab taking into account the different shims determining its height. Pull it to the ruler. Make the work about 1 to 2 m wide, and progress by area of equivalent size.
Start laying the pavement, taking care to scrupulously respect the layout of the manufacturer. Here, for more efficiency, each color corresponds to a format.
The new slabs are laid in Roman opus, shift the first row compared to the existing deck covering (water-jet cutouts).
Machine the straight edges of each freshly cut piece with the shredder to reproduce the irregular appearance of the other slabs.
Continue the installation respecting the principle of the mortar fired at the rule according to the height determined by the different shims set up on the entire concrete slab.
To reinforce the adhesion of concrete, the dusting technique consists of sprinkling a little cement over the area to be paved.
Once moistened by the capillary rise or by a light watering, the slabs are posed by exerting a slight pressure.
Check the flatness of the slabs using a ruler (here in wood). The adjustment can be done with a mallet or by pressure on the slab (depending on the fluidity of the mortar).
3 Grouting the slabs of a terrace
With each change of angle, grout the gutter elements with special PVC mastic-adhesive (it is resistant to expansion and shock).
Protect the gutter before trowel mortar to seal the risers. Let dry.
After complete drying of the mortar and before finishing work, carefully sweep the entire surface.
Pour the grouting mortar with a grout (a joint pocket) or an old saucepan.
Remove the excess mortar from the cat's tongue, checking that all gaps are filled.
Smooth the joints then clean the stains with a slightly damp sponge and regularly rinsed.
• Natural stone slabs
Burgundy type 20 x 20; 20 x 40;
40 x 40 and 40 x 60 cm in 2 cm
• Gray cement (Technocem 32,5R
• Jointing mortar
(Weber.joint pavement, Weber)
• PVC glue (Berner)
• Putty-glue (Berner)