FREQUENTLY ASKED QUESTIONS

additional useful information about limestone and sandstone

Limestones and sandstones


Why should you choose natural limestones and sandstones?

  • The limestones and sandstones have a high historical value, due they have been used for construction activities by different civilizations along the Mediterranean arc.
  • The natural stone is a kind noble material and, as such, it is durable and wear resistant, which is caused by its exposure to the environment and due its constant use. This has been proven along the time in those historical buildings in which our customers use our stones, places in which we participate currently in their restoration.
  • Our materials are a true gift given by the nature; they are sedimentary rocks, created over millions of years at the bottom of the sea.
  • The limestones and sandstones we sell contribute to the exclusivity of any project, each piece is unique; their different tones, colour variations, the possible veins in them, as well as the marine fossils that could be present, reaffirm their natural origin and their true authenticity.
  • The natural stones are a sustainable material due its high durability, due their properties in terms of thermal and acoustic insulation, and besides because its resistance to fire.

You can find all the benefits of the natural stones according to their use in our Applications section

What should I keep in mind when choosing a natural stone for my project?

  • The most important thing is to select the adequate kind stone, bearing in mind the intended use for it, treating it correctly since its original installation, and consequently providing the initial cleaning and subsequent maintenance. That way we will take full advantage of this material, thus enjoying all its beauty and comfort properties.
  • In consequence, the intended use often determines the most suitable finishing that the stone must experience on its surface and edges.
  • Always we suggest you before purchasing, taking a look to a physical sample of the stone to appreciate its colour, close to it, due in the photographs the colours may vary from one monitor to another, besides the possible variations that could exist, regarding the texture and tone, not appreciating directly the stone.
  • It is recommended that an expert, knowing perfectly the project, contrast the technical features of the material you are selecting versus the environmental conditions present in the place where you are going to install it.

Discover the most appropriate uses and the technical features of our stones, as well as the finishing for each one, in our Collection section

Should I apply any kind of treatment to the natural stone? What products should I use?

Limestones and sandstones the same as other noble materials, such as marble or wood, will enjoy a better looking, as well as experience a better performance and slower aging, if they are conveniently treated and protected during their use.

Rosal Stones, mainly advice you the following treatments:

 

Water-repellents

Their purpose is to reduce the absorption capacity of the materials.

These products are used for the protection of facades against the rainwater or the moisture, and for the treatment of rain gutters and copings outlining a slope.

They are suitable for vertical surfaces and useful on small ones that are placed horizontally with a slight slope (rain gutters, copings, etc.)

Their application regarding totally horizontal or large surfaces (although they are showing some slope), do not provide very reliable results, because the water, after several minutes, tends to penetrate the stone.

Recommended product: HYDROMAR (water-based)• Minimizes sensitivity to freeze-thaw cycles

  • Increases the useful life
  • Contributes to the fight against efflorescence
  • Protects against the development of mosses (greening)
  • Applied on the back of the stone, it avoids the manifestation of the humidity produced by the installation mortar, respecting the adherence of the same.
  • Available in packages of 1, 6 and 30 kg ready to dissolve in water and following a proportion of 1 to 9.
  • The performance according to the porosity shows an average of 4m²/kg of pure product.
  • It can be sprayed or applied through roller application over clean and dry or slightly damp surfaces.
  • Appearance: it does not create a visible layer or any shine, neither changes the colour in an appreciable way.

 

Oil-repellents

Their purpose is to offer protection against several kind of stains such as different liquids, fruit juices, oils, etc.

They also provide a water-repellent capacity and slightly consolidating properties, thus improving the wear resistance.

These products are especially indicated for pavements and areas that are expected to suffer a more intense and aggressive use.

Recommended product: Antioil

  • Minimizes sensitivity to freeze-thaw cycles
  • Increases the useful life
  • Contributes to the fight against efflorescence
  • Greater protection against the development of mosses (greening)
  • Facilitates the cleaning of the stone
  • Available in 10 and 25 litre containers and ready to use in a pure way
  • The performance according to the porosity shows an average of 4m²/litre.
  • It can be sprayed or applied through roller application over small surfaces or those ones of difficult access.  The material subject to the application must be clean and perfectly dry, 2 applications are recommended to achieve a total protection.
  • Appearance: it does not create a visible layer or any shine, neither changes the colour in an appreciable way. In white colours, you may see a very subtle difference between the treated areas in comparison to another one not treated.

 

HARDENING OF STONE THROUGH NANOCRYSTALIZATION

  • The objective is to achieve the hardening and consolidation of the stone
  • Seals pores and fissures permanently preventing any filtration.
  • After 15 days after application, the product solidifies and becomes insoluble and unchangeable glass, giving the stone greater resistance to abrasion, maximum impermeability, protection and hardness.
  • Prevents dirt from embedding in the stone and facilitates cleaning.
  • The treatment is applied on site by the developer of the product, once the entire surface is placed, cleaned and grout.
  • Penetration capacity of the product, between 5-10 cm.
  • Natural product, ecological and totally innocuous and colorless. Does not modify the appearance or color of the stone
  • Product guaranteed for 10 years.

 

Other treatments

Other water-repellents:
  • Water-repellent for the back side of the tiles, they prevent the moisture penetrate the tile from the inside
  • Water-repellents to rise the tones and providing a wet or shiny effect.
Consolidators, aging, against Graffiti

What systems could be used to place the natural stone in the facades?

  • Traditional system

Whenever you use a mortar to place the Natural Stone, it is necessary to use a reliable brand to obtain the appropriate guarantees. It must be specific for stone bonding and adequate regarding the porosity and weight of the boards you need to install. Of course, it is important to follow the technical guidelines described by the manufacturer of above-mentioned mortar.

The incorporation of stainless anchors is becoming more frequent and advisable due they provide a greater security and an improvement regarding the duration of bonding, these elements are especially recommended when the Stones are installed more than 2m high, being the most common procedure consist of using two anchors located in the same edge.

  • Ventilated facades with natural stone:

It is increasingly common to place natural stone in ventilated facades, however in the past the ceramics was a material extensively used for this kind applications.

For this placement system, it is necessary the machining of the stone boards, working exactly on their edges, and applying the design indicated by the technical director of the construction works. The details for this process will depend on the type of anchors or regarding the selected frames. It is important to highlight that limestones and sandstones should be used with a thickness of 3cm for this kind of facades.

OUR NATURAL STONES
From our own quarries, we obtain an exclusive range of natural stones, guaranteeing an excellent quality and adequate responsiveness. Limestones and sandstones of marked Mediterranean spirit perfectly responding to the aesthetic and functional needs of your project.
MOST COMMON USES
Natural stones for facades, decorative elements and restoration, and as well as for indoor and outdoor pavements. Systems for the massive construction and stonemasonry that represented the essence of our company for more than 30 years. Everything developed under modern and exhaustive production processes focused in quality, and backed by the UNE ISO 9001 and 14001 standards.
REPRESENTATIVE PROJECTS
The essence of the Mediterranean reflected, since 1985 around the world, through our natural stones in important and representative projects, such as private homes, restoration of historical monuments and public works.