Mortar for gluing ceramics and tiles: tips and preparation
The mortar for gluing ceramics and tiles is a fundamental element in the installation of coatings in interior and exterior spaces. This material is used to adhere ceramic pieces to the substrate, ensuring their fixation and durability over time.
In this article, we are going to learn about the different types of mortars that exist for gluing ceramics and tiles, as well as the differences between unmodified mortars (C1) and modified mortars (C2). Additionally, we will explore the additional features that modified mortars offer and the importance of deformability and adhesion in tile installation. We are also going to address the UNE 138002:2017 regulation, which regulates the use of traditional mortars.
Types of mortars for gluing ceramics and tiles
There are different types of mortars that are used to glue ceramics and tiles. Some of the most common are screed mortar and plaster mortar.
Screed mortar is used to prepare the support before installing the tiles. This type of mortar is applied to the existing surface, leveling it and creating a solid and stable base for the subsequent placement of the ceramics.
On the other hand, plaster mortar is used to apply a layer of mortar on the surface before laying the tiles. This layer of mortar not only improves the adhesion of the ceramics, but also allows small irregularities to be corrected and guarantees a uniform surface for installation.
Differences between unmodified (C1) and modified (C2) mortars
When choosing a mortar for gluing ceramics and tiles, it is important to know the differences between unmodified mortars (C1) and modified mortars (C2).
Unmodified mortars, also known as C1 mortars, are mainly composed of cement and sand. These mortars glue the tiles together through mechanical adhesion, that is, through the physical union between the ceramic and the mortar.
On the other hand, modified mortars, also known as C2 mortars, contain additives that give them additional characteristics. These additives can be polymers, resins or adhesives, among others. The presence of these additives allows a chemical adhesion between the mortar and the ceramic, which improves the resistance and durability of the installation.
Additional characteristics of modified mortars (C2)
Modified mortars (C2) offer a number of additional characteristics that make them highly valued in ceramic and tile installation.
One of the most notable benefits of C2 mortars is their extended open time. This means that the mortar remains in a fresh and workable state for a longer period of time, making it easier to handle and lay the tiles, especially in large work areas or in hot climates.
In addition, C2 mortars have greater tensile strength. This is especially important on floors or surfaces that will withstand heavy traffic, such as hallways or high-traffic areas. The greater tensile strength of the mortar ensures a solid bond between the ceramic and the substrate, avoiding detachments or cracks.
Another important characteristic of C2 mortars is their rapid setting. This means that the mortar hardens quickly after application, reducing waiting time and speeding up the installation process. This feature is especially useful on projects with tight deadlines, where ceramic installation needs to be done quickly and efficiently.
Importance of deformability and adhesion in tile installation
Deformability and adhesion are two key aspects in tile installation. These characteristics determine the ability of the mortar to adapt to the deformations of the substrate and to maintain a durable bond between the ceramic and the support.
The deformability of the mortar allows it to adapt to the movements and expansions of the substrate without breaking or detaching. This is especially important on surfaces subject to temperature changes or structural movements, such as underfloor heating or facades exposed to extreme weather conditions.
Adhesion, both mechanical and chemical, is essential to ensure a solid fixation of the tiles to the mortar. Mechanical adhesion occurs through the physical bond between the ceramic and the mortar, while chemical adhesion is based on the chemical interaction between these two materials. Both types of adhesion are necessary to ensure a durable, peel-resistant installation.
UNE 138002:2017 regulations on the use of traditional mortars
The UNE 138002:2017 regulation establishes the requirements and specifications for the use of traditional mortars in the installation of tiles and ceramics. This regulation aims to guarantee the quality and durability of the facilities, as well as the safety of users.
According to this regulation, traditional mortars (C1) should only be used in certain conditions, such as in the installation of ceramics with low water absorption or in interior coatings with low traffic. In these cases, traditional mortars offer sufficient adhesion and adequate performance.
However, in more demanding situations, such as on floors with high traffic or on exterior coatings exposed to adverse weather conditions, it is recommended to use modified mortars (C2). These mortars offer greater performance and resistance, ensuring a durable and safe installation.
The mortar for gluing ceramics and tiles plays a fundamental role in the installation of coverings. There are different types of mortars, such as screed and render, that are used to prepare the substrate before installation. In addition, a distinction is made between unmodified mortars (C1), which bond by mechanical adhesion, and modified mortars (C2), which have chemical adhesion and offer additional characteristics such as extended open time, tensile strength and rapid setting. Deformability and adhesion are key aspects in tile installation, ensuring a durable, peel-resistant bond. The UNE 138002:2017 regulation regulates the use of traditional mortars, recommending the use of modified mortars in more demanding situations.
