Marble adhesive suitable for indoor use
How Marble is Used – A Summary
A marble is a beautiful natural stone that has many uses in the home, especially as part of the interior décor. Marble can be finished in a variety of different ways, giving it a rich variety of options to fit nearly any decorative theme or style. The use of the proper adhesive to attach marble to a surface (usually a concrete base) is critical to ensuring durability, safety, and aesthetic appeal. This paper will provide a detailed overview of the different types of adhesive used to install a marble surface and discuss how adhesives are selected and how to install adhesive to marble surfaces.
I. Marble Adhesive Function for Indoor Surface Applications:
a. Marble adhesive serves the purpose of anchoring a marble to its substraight (concrete, plaster, etc.)
b. Marble adhesive fills in the small voids between the marble slab and its supporting surface to increase load-bearing capacity of the installation and/or to ensure long-term stability.
c. The use of an adhesive to joint the marble slabs eliminates the potential for a hollow space. This will minimize cracking of the entire installation and will help to prevent warping or curling of the marble edges.
It is essential to select the appropriate adhesive based on scientific studies detailing the physical and chemical properties of the marble and the techniques that were utilized to install the marble.
II. The most common types of cementitious adhesives for indoor application on marble are:
1. Cementitious Adhesive is comprised of cement that is modified with fillers, reinforcement fibers, and/or other materials.Cementitious adhesives can be used to install medium-sized stone products, such as ceramic and ceramic wall/tile, to concrete or other substrates. Advantages of using cementitious adhesives include their relative affordability, ease of installation and compatibility with a number of different types of substrates. The disadvantages of using cementitious adhesives are their relatively low flexibility and that typically they only deform a small amount or not at all.
Disadvantages of polymer modified mortar include: high cost of the material; and strict environmental and operational criteria associated with the application process.
A polymer-modified mortar is made by adding polymer emulsion or powder to a cement-based formulation.
Polymer-modified mortar provides improved adhesion between the two materials. The bond strength, flexibility and durability of the bond are all improved with the use of polymer-modified mortars.
As there is typically little deformation in most indoor substrates, polymer-modified mortars can be effectively used for indoor applications.
Performance Indicators for Adhesives Used in Indoor Applications
When selecting an adhesive to use indoors, the following types of performance indicators (technical data) should be taken into consideration:
Performance Indicator Measurement Evaluation Direction
Initial Bond Strength Ability to install with safety and speed, as well as having enough bond strength to hold up the installed materials. High
Final Bond Strength Long-term load bearing requirements will be satisfied. High
Open Time Time available for relocating the slab. High enough
Deformability (Modulus of Elasticity) Ability to keep the slab and substrate in relative position and with respect to other construction materials (i.e. due to moisture and/or temperature).Medium-High Shear Strength Helps to Prevent Delaminating Marble Used on Floors or Walls High Water Resistance/Durability Long Term Performance in Wet Environments Good
Recent Research in High Performance Epoxy And Polymer Modified Adhesives Shows Improvements In The Above Performance Characteristics
IV. Recommendations For Use Of Adhesives Indoors
Adhesives come in a variety of types to meet specific types of indoor projects.
Best Choice For Floor Or Wall In A Residential House Will Be A polymer Modified Mortar / Medium Range Cementitious Adhesives. These Have The Following Characteristics: Easy To Apply, Consistent Quality Of The Adhesive, And Reasonably Priced.
Wet areas should use a waterproof adhesive with polymer modification to secure substrate on flooring. Proper substrate preparation consists of cleaning all surfaces of any contaminating agents such as oils, dusts, release agents, and chemicals that could interfere with forming an effective bond. If the substrate is too dry prior to installing the adhesive, moisten slightly, not soaking, so adhesive can effectively bond to the substrate; allow this to dry before proceeding.
The supplier’s recommended amounts of component adhesive material must be followed for best results. This means that you must mix the adhesive correctly and thoroughly before application so that you have a homogenous and consistent paste before applying it to the substrate surface. The correct method of application is to use a notched trowel in dot and butter pattern. Use of the dot and butter method will assure that the entire granite tile slab and the adhesive are in contact with one another for maximum bonding area. When installing larger-format marble tiles, use back-coated adhesive to thus provide your installer with greater bonding area than would have resulted from the dot and butter method alone.
Open times of the adhesive from supplier
As with any other adhesive, the open time of the adhesive will vary according to ambient temperature/humidity at the time of installation and therefore it’s important to allow 24-48 hours for the curing process before placing a load on these marble or concrete surfaces.
In General, there is no one adhesive that is correct for every indoor application. However, by taking into account performance criteria, installation conditions, and budget, the desired adhesive could easily be found for any residential construction job. In conclusion, below is a comparison chart for most residential construction projects.
Cost, cementitious and polymer modified “thin-set” mortar are likely to provide satisfactory performance in residential installations. Conversely, because the cost of epoxy adhesives is quite high, they should only be used for installations that require a high-end product, large-format assembly, and/or any other very specialized projects. The correct methods of installing and performance criteria used during installation will determine whether the assembly is stable and the final assembly presents quality marble to the user.
