Choosing adhesive and grout with standards as a general guide
Introduction
First, a warning: This is a fairly technical guide. It is meant for intermediate to advanced tilers, but newbies can benefit from reading this too. If you find this sort of technical mumbo-jumbo boring, and don't want to read it, I have a recommendation for you:
Always read product specs and follow them. It can, and will, save you money and time. You'll learn alot as well.
Know this: I do not claim to be an expert on European Standards; I merely relay what I know. I don't have the documents themselves availible; I'm writing from memory. Please point out if I've mixed something up.
Onwards...
You may have noticed that most adhesives and grouts usually have a small collection of weird letter and number combinations in their specs. They may look like this:
BS EN 12004 C2F
Here's what this particular one means: Classified as
Cementious, Improved(2), Fast-setting adhesive, in compliance with the
British Standards and
European Norms, as specified in document
12004.
It's not as complicated as it seems, though it might be a bit confusing when you don't know what the letters and numbers mean.
Standards set a base line, which is the same as minimum performance requirement. A company which whishes to classify their products according to the existing standards, have to send product samples to independant laboratories, where the products will be tested to failiure. The lab will use methods specified in the relevant standards documents. A product may exceed the base line requirements, but for it to be classified, it must atleast meet them. The class and type description does not tell wether or not a product just manages to meet the standards specification, or if it exceedes it; neither does it say anything about the exact properties of a product. It does however state what minimum performance you can expect from the product in question. This is important, because the properties the classifications describe can be associated with certain applications. More on this as I go.
The low down, according to EN 12002, EN 12004, and EN 13888
These standards describe the general properties of materials classified according to them. If I remember correctly, EN12004 is the main standard for adhesives, and it describes properties, and specifies minimum performance levels.
EN12002 describes and specifies additional properties which adhesives and grouts classified according to EN12004 and EN13888 may have, specifically, transverse deformation, ie flexibility.
EN13888 deals with grouts. I'll go through them one by one.
EN12004
The types described in EN12004 are as follows:
Cx = Cementious, ie cement based bagged adhesives. Use a face mask when mixing, unless you want to risk asthma and/or cancer in the long run.
Dx = Dispersion, ie ready mixed adhesive, aka tubbed gear.
Rx = Resin, ie epoxy. Use appropriate methods and protective gear when you use this, unless you're willing risk nerve damage and other nastiness as a result of breathing the fumes.
The
x can be either 1 or 2. Explanation follows below.
The classes described in in EN12004 are as follows:
1 = Normal.
2 = Improved. Better adhesion and flexibility. Usable in most applications, in combinations with appropriate added properties.
F = Fast, ie rapid setting. Cures fast, and binds all, or almost all, of the water mixed into it chemically. A must when time is of the essence, or when working with most natural stone. Alot of natural stone can be discoloured by water, so you want to minimize the free water it's exposed to.
T = Tixotropical. That means it's loose when being handled, and fairly stiff when no being handled. That equals anti-slippage, a must for tiling walls, especially if you do not use support, such as spacers.
E = Extended open time. Useable atleast 20-30 minutes after application to a surface prepared according to manufacturer specs, with a surface and air temperature of 20 degrees celcius. Some are usable for up to an hour. Standard open time is around 10 minutes, depending on temperature and humidity.
An adhesive described as
C2TE, or
Type C, Class 2TE is
Cementious, Improved (
2), and Anti-slippage (
T), with an (
Extended) open time of no less than 20 minutes.
EN12002
Additional properties not described in EN12004 and EN13888 are described here.
Sx = Deformable (able to absorb a minimum amount of deformation as specified in the numerical suffix)
1 = Flexible (greater or equal to 2.5mm, but less than 5mm).
2 = Highly flexible (greater than 5mm)
While most C2 rated adhesives can handle 6-12 months old concrete, most C2/S1-2 Adhesives can handle anything from 1-3 months old concrete (or older, of course) without cracking.
The less dimensionally stable a substrate is, the more flexibility is needed. The additives which make adhesives flexible also tend to improve adhesion, so if the substrate and/or the tiles are really dense or non-absorbant, a flexible adhesive or additive might be needed.
EN13888
Grouts. The types described in EN13888 are as follows:
CGx = Cementious Grout.
RGx = Resin Grout. Epoxy, in other words. Used when there are special mechanical and/chemical resistance requirements, and/ sanitary requirements. Very seldom used in domestic applications.
The classes described in EN13888 are as follows:
1 = Normal
2 = Improved wear resistance and reduced water absorbation.
Final notes
As previously stated, the standards specify what minimum performance you can expect from a product. Since manufacturers develop their products themselves, the actual content of the products can vary greatly between brands, though they might have the same classification. Manufacturers design their products in systems, which are guaranteed to work when used together as long as you follow the product specs and guidelines.
Therefore, try to not mix different brands too much.
Knowing what the classes and types mean, makes it easier to differentiate between products, and saves you time when picking materials. They do not replace the individual specs and guidelines however, so always read them when you've narrowed down the selection.
If an adhesive or grout doesn't specify which standard it complies with, I won't use it, because it could be powdered pig for all I know.
I've probably made alot of spelling misstakes and missed things when I've edited this post; I'll correct them as I find them.
I hope you've enjoyed reading this, and I believe this is one of my longest posts to date. That says something, ey?
