Surface Bond Strengths of Various Construction Materials

Bond strength = Adhesion strength = Tensile strength = Peel strength = Die-shear strength = Die and substrate attachment strength = Centrifuge testing (constant acceleration) = Pull-off strength. Test are widely used to calculate the bond strength by dividing the maximum force by the bonding area.

Surface bond strength (the force needed to pull the units from the mortar is measured) is an essential factor in construction, particularly when bonding different materials together, such as in tiling, stone cladding, or when applying finishes like plaster. Here’s a general list of surface bond strengths for various construction materials. Please note that these values can vary based on factors like surface preparation, adhesive type, and environmental conditions:

1. Concrete

   • Typical Bond Strength: 1.5 to 2.5 MPa (217 to 362 psi)
   • With Special Adhesives: Up to 4.0 MPa (580 psi) or higher

2. Masonry (Brick, Block)

   • Typical Bond Strength: 0.7 to 1.5 MPa (100 to 217 psi)
   • With Special Adhesives: Up to 3.0 MPa (435 psi)

3. Plaster

   • Typical Bond Strength: 0.5 to 1.0 MPa (72.5 to 145 psi)
   • Enhanced Plaster (Polymer-modified): Up to 2.0 MPa (290 psi)

4. Gypsum Board (Drywall)

   • Typical Bond Strength: 0.3 to 0.7 MPa (43.5 to 100 psi)
   • With Reinforcement: Up to 1.0 MPa (145 psi)

5. Wood (Plywood, OSB)

   • Typical Bond Strength: 1.0 to 2.0 MPa (145 to 290 psi)
   • For Specific Applications (e.g., flooring adhesive): Up to 3.0 MPa (435 psi)

6. Steel (Bare, Primed)

   • Typical Bond Strength: 1.0 to 3.0 MPa (145 to 435 psi)
   • With Special Primers/Adhesives: Up to 4.0 MPa (580 psi)

7. Ceramic Tiles

   • Typical Bond Strength: 0.5 to 1.5 MPa (72.5 to 217 psi)
   • With Enhanced Adhesives: Up to 3.0 MPa (435 psi)

8. Natural Stone (Marble, Granite)

   • Typical Bond Strength: 1.0 to 3.0 MPa (145 to 435 psi)
   • With Specialized Adhesives: Up to 5.0 MPa (725 psi) or higher

9. Glass

   • Typical Bond Strength: 0.3 to 1.0 MPa (43.5 to 145 psi)
   • With Specialized Adhesives (Silicone, Epoxy): Up to 3.0 MPa (435 psi)

10. PVC (Polyvinyl Chloride)

    • Typical Bond Strength: 0.5 to 1.5 MPa (72.5 to 217 psi)
    • With Specialized Adhesives: Up to 2.5 MPa (362 psi)

Key Factors Affecting Bond Strength:

• Surface Preparation: Proper cleaning, roughening, or priming can significantly enhance bond strength.
• Adhesive Type: The choice of adhesive (e.g., epoxy, cementitious, polyurethane) is crucial in achieving desired bond strength.
• Environmental Conditions: Temperature, humidity, and exposure to water can affect the bond strength over time.

What does standard says – How much should be the bond strength?

1. For tile adhesive, as per Indian standard IS 15477 – 750N - 0.13 N/Sqmm.
2. For tile adhesive, as per BS EN 12004 – 0.5 N/Sqmm.
3. For tile adhesive, , Australian Standards 2358 "Adhesive for Ceramic Wall Tile" which fixes a minimum tensile bond strength of cement based adhesives after seven days.  This bond strength requirement is a minimum of 0.15 MPa (22 psi).
4. ASTM F 1147-05 – Adhesion to substrate shall be >20 Mpa
5. CSA A23.1 gives a minimum bond strength for toppings of 1.0 MPa (145 psi)
6. Tensile adhesion strength as per Singapore HDB method shall be of - average strength  > 0.80 N/Sqmm and individual strength  > 0.60 N/Sqmm

Which surface can hold how much load:

1. Concrete- Mechanically prepared to provide a roughened porous solid surface - 60 kg/m² 
2. Sand/Cement Render - Applied to solid open porous roughened concrete, brick, or masonry surface. 32 kg/m²
3. Paper-faced plasterboard generic, Gyprock plasterboard - 32 kg/m² (Remove wallpaper, vinyl and paint finishes)
4. Gyprock Aquachek Sheet fixing @ 200mm centres (with/without Waterproof membrane) -12.5 kg/m² 
5. Gyprock Aquachek Sheet fixing @ 100mm centres (with/without Waterproof membrane) - 32 kg/m² 
6. Fibre Cement Wallboard# Sheet fixing @ 200mm centres - 20 kg/m²
7. Fibre Cement Wallboard# Sheet fixing @ 100mm centres - 32 kg/m²
8. Fibre Cement sheets for External Facades^ 
1. James Hardie EasyLap BGC – 50kg/m2
2. Innova Stonesheet  - 40kg/m2
9. Gypsum Plaster can support a maximum weight of 20kg/m² 
10. Gypsum Plasterboard direct can support a maximum weight of 32kg/m².
11. Wood based sheet can support 30 Kg/m2.
12. Foam cored tile backing boards and fiber cement boards can support 60 Kg/m2
13. Gypsum fiber boards can support approx. 35-40 Kg/m2.
14. Masonry and blockwork (May require rendering prior to the installation of tiling - refer to AS 3958.1 – 2007, Section 4.5 refer to sand/cement render). 32 kg/m² 
15. Hebel Block Walls/Hebel Wall Panels 32kg/m² max. (Internal walls only. No additional mechanical fixings to be used)

Let me know your comments below....