Decision Analysis

Fasteners are critical components of a building. Choosing the right fastening system can prove decisive in terms of the longevity and safety of the roof. Through this brochure, REALM gives you a clear guide to the most suitable fasteners for different roofing application. Specifying the right fasteners, for the right application is critical, because inadequate fasteners can cause major defects in a project, including replacement of roofs, water leakage, damage to machinery and other construction related issues. Since standard types and grades of fasteners are adequate in many construction application; fastener selection is usually based on industry standards, building code requirements and design loads. In some cases, it is deemed feasible to leave the fastener selection to the discretion of contractors or building product fabricators, allowing them to select fasteners based on cost, convenience and trade practices. However, with the emphasis now on long term performance of a roof and because builders and engineers need to be able to depend on the durability, quality and performance of the fasteners that secure the roof; fastener selection has evolved into one of the most crucial aspects of the building design.

That is why expert judgement is required to choose fasteners that:

• Perform as intended

• Are dependable and economical

• Last equal to or more than the life span of the building.

Factors effecting fastener performance include:

• Structural capacity and safety factor.

• State and dynamic load resistance.

• Pull-out and pull-over resistance.

• Shear resistance of fastener and attached materials.

• Corrosion resistance in conditions of use.

• Long term seal guarantee.

• Seal against liquid or gas leakage (if required).

• Constructibility, practicality and inspect ability.

• Compatibility with design intent and aesthetics

• Removability or other special requirements.

• Service life exceeds that of attached materials.