Opus incertum (planchoncillo): price per m², types and installation
What is opus incertum?
Opus incertum, also called planchoncillo, is a paving made of natural stone slabs in irregular shapes, with free-form outlines and a rustic top surface. All the pieces on a pallet have a very similar thickness (normally between 2 and 4 cm) because they are hand-selected and palletised, which makes laying much easier. It is used for paths, patios, terraces and entrances, and also as cladding for walls and facades.
Quartzite or slate: which one to choose?
Quartzite: a very hard, durable stone with warm, shifting tones (yellow, gold, bronze brown, bluish, silver). It is the best-selling option for garden paths and paving thanks to its bright look and great durability.
Slate: in grey, black or rust tones, it has a more sober, contemporary feel. It is a very waterproof stone, so it also works very well as cladding for facades and walls against damp.
How much does opus incertum cost per m²?
It is sold by the pallet of about 25 m². These are the indicative prices from our catalogue (always check the product page for the current price):
Grey slate planchoncillo: from €379 per pallet (about €15.2/m²). Red-brown planchoncillo: from €379.92 per pallet (about €15.2/m²). Gold and blue planchoncillo: from €400.21 per pallet (about €16/m²). Bluish and bronze brown planchoncillo: from €414.88 per pallet (about €16.6/m²). Two-tone silver planchoncillo: from €447.62 per pallet (about €17.9/m²). Yellow planchoncillo: from €448.94 per pallet (about €18/m²).
Buying a full pallet gives the lowest cost per m²; for small areas, work out the number of pallets by rounding up and allow 5-10% extra pieces for cuts and offcuts.
How to lay opus incertum
There are two valid ways to lay it:
On a sand bed: the option we always recommend when possible. It is easier and faster, and the result is stable, comfortable and long-lasting. You prepare a compacted gravel base, a levelled layer of sand and then set the pieces with narrow joints.
Fixed with mortar: suitable for high-traffic areas or slopes. The pieces are set on mortar and the joints are filled with grout.
In both cases it is important to do a dry layout on the ground first, combining large and small pieces like a puzzle, and not to leave joints too wide. To clad walls or facades, choose pieces no thicker than 3 cm.
Tips for choosing
For a garden path, yellow or gold quartzite brightens the area and goes well with green plants. If you want a modern style or want to use the paving on a facade too, grey or black slate is a safe bet. If you are unsure about quantity or colour, write to us with the measurements of your project and we will advise you.
Frequently asked questions
How much does opus incertum cost per m²?
It depends on the stone and colour: from about €15.2/m² for grey slate and red-brown to about €18/m² for yellow, calculated on 25 m² pallets. Always check the product page for the current price.
How many m² does a pallet of opus incertum cover?
A pallet covers about 25 m². It is advisable to add 5-10% extra pieces for cuts and offcuts.
What is the difference between quartzite and slate opus incertum?
Quartzite is a very hard stone with warm tones (yellow, gold, bronze brown, bluish, silver) and is the best seller for garden paths. Slate, in grey, black or rust tones, is more sober, very waterproof and also suitable for cladding facades and walls.
Is it better to lay opus incertum on sand or with mortar?
We recommend laying it on a sand bed whenever possible, because it is easier and the result is stable and long-lasting. Mortar is suitable for high-traffic areas or slopes.
What thickness should opus incertum be to clad a wall or facade?
To clad walls or facades, choose pieces no thicker than 3 cm.
