Understanding The Properties and Uses of Adhesives for the Installation of Ceramic Tiles, Marble & Natural Stones
INTRODUCTION: The Tiling System
A tiling finish is a system comprising no less than the substrate, bedding (adhesive), ceramic tiles (or stone/marble veneers), grouted joints and movement joints. All the components are equally important as they are inter-related. Adequate compatibility must exist between them for the system to function collectively. The system can only be as strong as the weakest component or, in some cases, worse.
1. Types of Adhesives
Cementitious (C) : 1-component, to be mixed with water only
Cementitious (C) : 2-component, mix Part A Powder + Part B Liquid
Dispersion (D) : 1-part, ready-to-use paste, no mixing required
Reaction Resin (R) : 2-component, mix Part A Resin + Part B Hardener The hardening process occurs by chemical reaction; typically resin-based adhesives are epoxies and polyurethane products.
2. Adhesive Classifications & Their Fundamental Performance Characteristics
In the EN 12004 and MS ISO 13007-1 Standards, adhesives are grouped into 3 types :
- C (Cementitious) - D (Dispersion) - R (Reaction-resin)
The fundamental characteristics of Cementitious Adhesives include Tensile Adhesion Strength based on various curing conditions and an Open Time of 20 minutes. Additional properties for cementitious adhesives include the following:
F : Fast-setting (early tensile adhesion strength)
T : No vertical slip
E : Extended open time
S1 : Deformable (deformity of 2.5mm to 5mm)
S2 : Highly Deformable (deformity of 5mm)
CLASSIFICATION & PERFORMANCE CRITERIA
EN 12004 / 12002 and MS ISO 13007-1
(MAPEI PRODUCTS)
Classification
MAPEI Product Examples Characteristics Requirement
C1 – Normal
Keraset Kerabond T Kerafloor
Tensile Adhesion Strength @ 28 days Tensile Adhesion Strength after water immersion, heat aging and freeze-thaw cycles Open Time @ 20 mins
0.5 N/mm2
0.5 N/mm2
0.5 N/mm2
C2 – Improved
Adesilex P9 (C2TE) Keraflex (C2TE) Keraflex Maxi S1 (C2TE/S1) Keracrete+Powder (C2T)
High Tensile Adhesion Strength Tensile @ 28 days Adhesion Strength after water immersion, heat aging and freeze- thaw cycles Open Time @ 30 mins
1.0 N/mm2
1.0 N/mm2
0.5 N/mm2
F – Fast setting
Granirapid (C2F/S1)
Early Tensile Adhesion Strength after 6 hours
0.5 N/mm2
T – Slip Slip
0.5 mm
S1 – Deformable
Keraflex Maxi S1 Kerabond T + Isolastic 50
S2 – Highly Deformable
Kerabond T + Isolastic
Transverse Deformation (special deformable characteristic for cementitious adhesives only)
2.5mm to < 5mm
5mm
E – Extended Open Time Extended open time @ 30 mins : Tensile Adhesion Strength
0.5 N/mm2
After not less than 30 min
3. Properties of Cementitious Adhesives Tensile Adhesion Strength The individual tensile adhesion strength, in N/mm2, is derived from the total load (in Newtons) divided by the bonding area (in mm2) using 50x50mm fully vitrified tiles. Testing is carried out based on 28-day curing.
- After Water Immersion: Test specimens are conditioned for 7 days and immersed in water for another 20 days according to the relevant Standards condition before conducting the pull-out test on the 28th day.
- After Heat Aging: Test specimens are conditioned for 14 days and then placed in an air-circulating oven for
another 14 days according to the relevant Standards condition.
Open Time
With reference to EN 12004 & MS ISO 13007-1, Open Time is defined as the maximum interval, after application of the adhesive, at which tiles can be embedded onto the applied adhesive and still meet the specified tensile adhesion strength requirement. Open time can have a significant impact on the tiling system. (i) When a product has passed its Open Time, the tile fixer must scrape off the adhesive and apply fresh material;
(ii) If skinning occurs on the surface of the adhesive while it is still fresh, the tiler must break the skin by re-
trowelling. Nevertheless, it is best not to spread too wide an area to avoid lapsing of the adhesive’s open time.
As a guide, you should not spread the adhesive further than an arm length’s distance. On site, tiles should be placed while the adhesive is still fresh, ideally within the first 10~15 minutes of the adhesive spread. All C1 & C2 cementitious adhesives will have to meet the fundamental criteria of minimum tensile adhesion strength of 0.5 N/mm2 after no less than 20 minutes of Open Time (23oC & 50% R.H.) Note: Open Time varies with different product formulations. In addition, the open time for a particular formulation is affected by humidity, temperature and wind conditions on site.
Extended Open Time
When a product meets the classification for “Extended Open Time”, it means the product meets the additional characteristic of tensile adhesion strength of 0.5 N/mm2 at not less than 30 minutes of Open Time (23oC & 50% R.H.). This class of adhesives are denoted with the letter “E”.
Setting Time
Most adhesives are Portland Cement-based and are normal-setting, regardless of strength class C1 or C2. Normal setting adhesives require a final cure time of 28 days and as such, all tensile adhesion strength tests are based on 28- day curing. However, there are Fast-setting adhesives with rapid hydration properties that can achieve early tensile strength. When products meet the fast-setting performance criteria, the product classification is denoted with “F”.
Deformability
Deformability is defined as the capacity of a hardened adhesive to be deformed by stresses between the tile and the fixing surface (substrate) without loss of adhesion or damage to the installed surface. This special characteristic is denoted with “S1” or “S2” in the product classification.
Slip
Slip is defined as the downward movement of a tile applied to a combed adhesive layer on a vertical surface. This property is important for wall and façade installations. Adhesives with slip resistance meeting the Standard’s requirement are denoted with the letter “T”.
4. How Do You Select the Right Adhesive for a Specific Application
In selecting the adhesive, it is important to understand and consider the layers that make up the tiling system as well as the application and service conditions:
a) What is the Substrate Type?
Substrate examples include concrete, precast concrete, cement + sand render / screed, existing tile, plywood, gypsum board, calcium silicate board, cement backer board, metal.
b) What is the Finishing Material?
Tiles: determine the type (ceramic / homogeneous / glass mosaic), size & weight.
Note: Generally, homogeneous tiles or porcelain tiles are very dense and have low water absorption. In order to have good mechanical grip onto these tiles (especially the ones with <0.5% water absorption), C2 adhesives with high tensile strength and better water retentivity characteristic will have better performance and adhesion compared to C1 products. For such installations, products like KERAFLEX MAXI S1, KERAFLEX as well as some two-component products are ideal.
Marble / Granite: determine whether natural, artificial or agglomerate, size, and stone characteristics such as sensitivity to moisture, dimensional stability and porosity.
c) What are the Application and Service Conditions?
Internal or External?
Floor or Wall?
Swimming Pool: grounded or suspended?
What are the stress factors, for example, differential movement due to thermal variations, vibration, deflection etc.?
5. How to Specify the Tile Adhesive for the Installation of Tiles,
Marble and Natural Stones Establish the conditions which the tile and stone installations will be subject to, then determine the performance characteristics of the adhesive that are necessary to perform under these conditions. The reference Standards commonly used internationally and in Malaysia are: EN 12004: Specifications & Definitions for Tile Adhesives EN 12002: Deformable Adhesives MS ISO 13007-1: Specifications & Definitions for Tile Adhesives Note: Old standards such as ANSI 118.4, ANSI 118.1, BS 5980 are deemed obsolete and are replaced by the EN & MS ISO Standards given above.
6. Considerations Required for the Substrate
Receiving substrates must be sound, stable, clean and free of dust, dirt, laitance, oil, grease and any contaminant that may hinder good adhesion. Sufficient curing of substrate renders and screeds is necessary and should be observed. When using formulated adhesives, soaking of tiles is not necessary. If in doubt, refer to the Manufacturer’s technical data sheet. Always wipe clean the backs of tiles (adhesion face) to remove all dust and contaminants before laying.
7. Mixing and Application of Adhesives
Mixing:
Cementitious adhesives: when mixing powder and liquid components together, whether the product is 1- or 2-component, you should be able to obtain an optimum mix by following the manufacturer’s recommended mix ratio. In some cases, some adjustment is acceptable to achieve a specific mix consistency - please refer to the Manufacturer for advice. Do not mix by hand - always use a mechanical mixer to obtain a homogeneous paste. Mix ratios vary with different product formulations. Always refer to the manufacturer’s instructions for recommended mix ratios. Regardless of whether it is a 1-component or 2-component pre-packed cementitious adhesive, do not add Portland cement to the mix.
Open Time Reminder:
The EN 12004 & MS ISO 13007-1 Standards specify an open time of 20 mins. with Tensile Adhesion Strength of
0.5 N/mm2 . Tiles must always be placed within the open time of the adhesive otherwise skinning will occur on the surface and adhesion will be compromised. As a guide, you should not spread the adhesive further than an arm length’s distance. Tiles should be placed when the adhesive is still fresh within 15 minutes of the Open Time.
Application:
Always ensure that a scratch coat of adhesive is applied onto the substrate with the flat side of the notched trowel to fill out any roughness in the substrate. This ensures good contact between the substrate and the adhesive layer. Then apply more adhesive with the notched side of the trowel with an appropriate-sized notch (the bigger the tile, the bigger the notch). For large format tiles, also apply a thin coat of adhesive to the back of the tile.
Adhesive Thickness – How thick should it be?
Thin, medium or thick bed? Most cementitious adhesives are formulated to be applied thin (normally <10mm) based on a cement/fine sand ratio of 1:1.
For medium bed adhesives, the cement/sand ratio differs slightly and are normally formulated with some coarse sand to enable a slightly thicker bed of up to 15mm. MAPEI’s medium bed adhesives include Keraflex Maxi S1 (C2TE/S1) and Kerafloor (C1). Note: Installations that are done with bedding thicknesses of 20mm or more in one operation are no longer referred to as “an adhesive method”. They are normally termed as thick bed installations and the cement/sand mix ratio is typically 1:3. This method of bedding tiles or natural stones is becoming a thing of the past due to the significant risks involved.
Adjustability Time:
Depending on product type, all adhesives have an adjustability time during which the position of the tile can be adjusted.
8. Common Mistakes in the Use of Tile Adhesives and How to Avoid Them
Adhesive’s Open Time:
Do not spread the adhesive further than an arm’s length distance. Tiles should be placed when the adhesive is still fresh during the trowelling process. (This point is repeated several times in this document due to its importance.)
Presence of Dust & Dirt:
The substrate and the backs of tiles must be clean. Although you do not need to pre-soak homogeneous tiles, you must always remove dust from the backs of tiles by using a damp cloth or sponge.
Curing of cement mortar screeds/renders:
Sufficient time must be given for cement mortar screeds/renders to cure. This ensures proper hydration and enables hygrometric shrinkage to take place. Sometimes, the surface may appear dry but if sufficient time is not given for curing, the mortar bedding is still green inside and this may contribute to failures.
Porcelain Tile Installation
For non-absorbent tiles like Porcelain/Homogeneous tiles, always use a higher strength, single-component adhesive eg KERAFLEX (C2TE) or KERAFLEX MAXI S1 (C2TE/S1).
Outdoor Applications / Swimming Pools
Important points to remember
Always provide shelter from direct sunlight and rain.
Surfaces that are hot need to be wetted down to cool the surface.
Always allow sufficient time for curing to take place before filling the pool with water.
Conclusions:
In selecting the right adhesive and establishing the right budget for successful installation, considerations must be given to:
Performance requirements relating to the project
Type of finishing material
Type of receiving substrate and its condition
Service conditions that the installation will be subject to
Doing it right the first time saves you considerable time and money.
BQ SPECIFICATIONS
A. Installation of Porcelain Tiles on Wall and Floor
Size: 800mm X 800mm
1. For Slurry, Render and Screed 2. Adhesive
3. Grout
PLANICRETE SP KERAFLEX MAXI S1 Powder KERACOLOR
800mm × 800mm Porcelain Tiles to lay with MAPEI’s KERAFLEX MAXI S1 Powder (C2TE/S1) High performance cementitious adhesive according to Manufacturers’ specifications, onto cement + sand screed substrate (1:3) Fortified with MAPEI’s PLANICRETE SP latex admixture; and grout with Mapei’s Keracolor Cementitious ground (colour to be selected by architect).
B. Installation of Porcelain Tiles on Wall and Floor
Size: 600mm X 600mm, 400mm X 400mm, 300mm X 600mm,
1. For Slurry, Render and Screed
2. Adhesive
3. Grout
PLANICRETE SP KERAFLEX Powder KERACOLOR
600mm × 600mm Porcelain Tiles to lay with MAPEI’s KERAFLEX Powder (C2TE) according to Manufacturers’ specifications, onto cement + sand screed substrate (1:3) Fortified with Mapei’s PLANICRETE SP latex admixture; and grout with MAPEI’s KERACOLOR Cementitious ground (colour to be selected by architect).
BQ SPECIFICATIONS
C. Installation of Ceramic Tiles on Wall and Floor
Size: 600mm X 600mm, 400mm X 400mm, 300mm X 600mm,
1. For Slurry, Render and Screed
2. Adhesive
3. Grout
PLANICRETE SP KERABOND T Powder KERACOLOR
600mm × 600mm Porcelain Tiles to lay with MAPEI’s KERABOND T Powder (C1T) according to Manufacturers’ specifications, onto cement + sand screed substrate (1:3) Fortified with Mapei’s PLANICRETE SP latex admixture; and grout with MAPEI’s KERACOLOR Cementitious ground (colour to be selected by architect).
D. Installation of Natural Stone on Wall and Floor
Size: 600mm X 600mm, 400mm X 400mm, 300mm X 600mm,
1. For Slurry, Render and Screed
2. Adhesive
3. Grout
PLANICRETE SP KERABOND T Powder + ISOLASTIC 50 KERACOLOR
600mm × 600mm Porcelain Tiles to lay with MAPEI’s KERABOND T Powder mix with ISOLASTIC 50 (C2/S1) according to Manufacturers’ specifications, onto cement + sand screed substrate (1:3) Fortified with Mapei’s PLANICRETE SP latex admixture; and grout with MAPEI’s KERACOLOR Cementitious ground (colour to be selected by architect).
PROPOSED ADHESIVES FOR THE INSTALLATION OF TILE, MARBLE,
GRANITE & NATURAL STONE
Type of Finish Location Type of Substrate Recommended MAPEI Product
Adhesive Classification in compliance with ISO
13007-1 EN 12004/1002
Natural Marble Wall & Floor Concrete Cementitious
render / screed
KERABOND T + ISOLATIC 50
(two-component) or Keraflex Maxi S1
C2/S1
C2TE/S1
Natural Marble Agglomerate & Artificial Marble
Wall & Floor – Porous Stones
that are subject to staining
Concrete Cementitious
render / screed
GRANIRAPID (two-component)
C2F/S1
Natural Marble Agglomerate & Artificial Marble
External / Internal Wall Stone Sizes >600x600x20mm
Concrete Cementitious
render / screed Deformable
substrates such as plywood, cement board, dry wall
KERABOND T + ISOLASTIC
(two-component) C2/S2
PROPOSED ADHESIVES FOR THE INSTALLATION OF TILE
Type of Finish Location Type of Substrate Recommended
MAPEI Product
Adhesive Classification
in compliance with ISO
13007-1 EN 12004/1002
Homogeneous Tile Wall & Floor Concrete Cementitious
render / screed
KERAFLEX (single component
adhesive) C2TE
Ceramic Tile (water absorption
<12%) Wall
Concrete Cementitious
render / screed
KERAFLEX (single component
adhesive)
C2TE
Glass & Ceramic Mosaic
Wall Concrete Cementitious
render / screed
KERABOND T WHITE + ISOLASTIC 50 (two-component)
C2/S1
Ceramic Tile Homogeneous Tile Glass & Ceramic
Mosaic
Wall
Deformable substrates such as plywood, cement board, dry wall
KERABOND T + ISOLASTIC
(two component)
C2/S2
MAPEI SYSTEM FOR TILE INSTALLATION FOR SWIMMING POOL
Application
Recommended MAPEI Product
Adhesive Classification in compliance with ISO13007-1
EN 12004/1002
1. For Slurry, Render and Screed Planicrete SP + Portland Cement + Sand n.a.
2 i) Adhesive for Tile Kerabond T + Planicrete 50 C2T
2 ii) Adhesive for Glass Mosaic Kerabond T White + Isolastic 50 C2/S1
2 iii) Rapid Installation Granirapid C2F/S1
3. Grout Keracolor FF+ Fugolastic / Ultracolor Plus CG2
4. Movement Joints Mapesil AC Silicone Sealant (+FD Primer) n.a.
Classification:
C2 : Improved Cementitious Adhesive (High Performance, High Tensile Adhesion Strength)
F : Fast setting, Early Tensile Adhesion Strength after 6 hours
T : Property of No Vertical Slip
E : Property of Extended Open Time
S1 : Deformable Adhesive
S2 : Highly Deformable Adhesive
DRAWING NO.1
DETAIL DRAWING: PORCELAIN TILE INSTALLATION
CONCRETE
LEVELLING SCREED
ADHESIVE: KERAFLEX
LEVELLING SCREED: Portland Cement + Sand fortified with PLANICRETE SP
(including slurry coat with Cement + PLANICRETE SP)
GROUT:
KERACOLOR SF / FF + FUGOLASTIC
DRAWING NO.2
TYPICAL DETAIL DRAWING: WALL TILING WITH PORCELAIN TILE
CONCRETE
OR
BRICK WALL
LEVELLING MORTAR / RENDER: PLANICRETE SP + Portland Cement
+ Sand Mix
GROUT: KERACOLOR (Mix with Water or FUGOLASTIC)
FINISH : 300 x 600mm Porcelain Tile
ADHESIVE: KERAFLEX
DRAWING NO.3
HORIZONTAL INSTALLATION:
INSTALLATION OF GRANITE, MARBLE & NATURAL STONE TYPICAL DETAIL
CONCRETE
LEVELLING SCREED
ADHESIVE: KERAFLEX MAXI S1 or KERABOND T Powder + ISOLASTIC 50
WATERPROOFING: MAPELASTIC
LEVELLING SCREED: Portland Cement
+ Sand fortified with PLANICRETE SP
GROUT: KERACOLOR SF / FF
DRAWING NO.4
TYPICAL DETAIL DRAWING: WALL TILING WITH MARBLE / GRANITE
CONCRETE
OR
BRICK WALL
LEVELLING MORTAR / RENDER: PLANICRETE SP + Portland Cement + Sand Mix
ADHESIVE : KERABOND T + ISOLASTIC 50
or KERAFLEX MAXI S1
GROUT: KERACOLOR (Mix with water or FUGOLASTIC)
FINISH : Marble / Granite
DRAWING NO.5
DETAIL DRAWING:
SWIMMING POOL – WATERPROOFING & TILE INSTALLATION
CONCRETE
LEVELLING SCREED
ADHESIVE: GRANIRAPID or
KERABOND T WHITE + ISOLASTIC 50
WATERPROOFING: MAPELASTIC
LEVELLING SCREED : Portland Cement + Sand fortified with PLANICRETE SP
(including slurry coat with Cement + Planicrete 50)
GROUT : KERACOLOR FF + FUGOLASTIC or ULTRACOLOR PLUS
DRAWING NO.6
TYPICAL DETAIL DRAWING: WALL TILING WITH MOSAIC
Note: Alternative option for leveling is to use MAPEI’s Nivoplan, a pre-packed leveling mortar for concrete and brick walls.
CONCRETE
OR
BRICK WALL
LEVELLING MORTAR / RENDER: PLANICRETE SP + Portland Cement + Sand Mix
ADHESIVE: KERABOND T WHITE
(mix with ISOLASTIC 50)
GROUT: KERACOLOR (mix with water or FUGOLASTIC)
FINISH : Mosaic
RECOMMENDED SELECTION OF TILE ADHESIVES FOR DIFFERENT SUBSTRATES
Substrate Recommended
Adhesive Class Remarks
Concrete & Precast Concrete Panels
Kerabond T + Isolastic C2/S2 Class 2 Improved Adhesive : 2 component Highly Deformable adhesive and superior bonding.
Keracrete + Keracrete Powder
C2T Class 2 Improved Adhesive: 2 component Polymer Modified Portland Cement Adhesive Mortar with slip resistance.
Adesilex P10 + Isolastic 50
C2TE/S1 Class 2 Improved Adhesive : 2 component adhesive with good initial adhesion strength and good deformity and no vertical slip.
Granirapid C2F/S1 Class 2 Improved Adhesive (F) – 2 component adhesive system with rapid hydration properties and good deformity.
Keraflex C2TE Class 2 Improved Adhesive : 1 component CBA with fair deformity, extended open time and good slip resistance.
Cement Screed / Render
Keracrete + Keracrete Powder
C2T Class 2 Improved Adhesive : 2 component Polymer Modified Portland Cement Adhesive Mortar with good slip resistance.
Adesilex P10 + Isolastic 50
C2TE/S1 Class 2 Improved Adhesive : 2 component adhesive with good initial adhesion strength and good deformity and no vertical slip.
Keraflex C2TE Class 2 Improved Adhesive : 1 component CBA with fair deformity, extended open time and good slip resistance.
Plywood
Kerabond T+ Isolastic C2/S2 Class 2 Improved Adhesive : 2 component Highly Deformable adhesive and superior bonding.
Keraflex C2TE Class 2 Improved Adhesive : 1 component CBA with fair deformity, extended open time and good slip resistance.
Adesilex P22 (wall only) D1TE 1-part Ready-to-use Dispersion adhesive.
Gypsum Board Drywall / AAC Block
Kerabond T+ Isolastic C2/S2 Class 2 Improved Adhesive : 2 component Highly Deformable adhesive and superior bonding.
Keracrete + Keracrete Powder
C2T Class 2 Improved Adhesive : 2 component Polymer Modified Portland Cement Adhesive Mortar with good slip resistance.
Keraflex C2TE Class 2 Improved Adhesive : 1 component CBA with fair deformity, extended open time and good slip resistance.
Metal & Stainless Steel
Keralastic R2 2-part Polyurethane adhesive – Reaction Resin Type
Keraquick + Latex Plus
C2FT/S2 Class 2 Improved, Fast-setting : 2 component, high performance, fast-setting and highly deformable cementitious adhesive.
Existing Tile
Keracrete + Keracrete Powder
C2T Class 2 Improved Adhesive : 2 component Polymer Modified Portland Cement Adhesive Mortar with good slip resistance.
Granirapid C2F/S1 Class 2 Improved Adhesive (F) – 2 component adhesive system with rapid hydration properties and good deformity.
Keraflex C2TE Class 2 Improved Adhesive : 1 component CBA with fair deformity, extended open time and good slip resistance.
Note :This selection guide shall be referred in conjunction with selection of adhesives according to different types of tile and stone finishes. There may be a choice of several products that can be used for the application, depending on site conditions and usage. The Classes (1) and (2) are with reference to EN 12004 and ISO 13007-1 Standard for Adhesives for Tile and Stone for Cement Based Adhesives. Please note that the above chart is a recommendation for general applications. Kindly contact our Sales or Technical Services Department to confirm the selection for your applications or specifications.
MAPEI Malaysia Sdn Bhd
D3A-10, Block D3A, Dana 1 Commercial Centre, Jalan PJU 1A/46, 47301 Petaling Jaya, Selangor
Tel: (03) 7842 9098 • Fax: (03) 7842 6197 • www.mapei.com.my • [email protected]