Cover Feature Story
Roofing specification warned against mixing incompatible Dry Fix components
Construction firms are being warned that substituting individual roofing components to reduce project costs could create additional expense if the products have not been designed and tested to work together as part of a complete roof system.
RUSSELL Roof Tiles has highlighted the potential risks associated with value engineering roofing specifications, particularly as Dry Fix systems become increasingly common in modern roof construction.
The manufacturer says compliance with the relevant British Standard should be treated as the starting point when selecting roofing products, rather than confirmation that individual components will perform effectively when combined with products from other manufacturers.
The warning comes amid continued pressure on construction costs, with contractors and developers looking for ways to reduce expenditure during procurement and construction.
Scott Summers, regional sales manager for Russell Roof Tiles, has more than 40 years of experience in the roofing industry. He began his career as a roofer before moving into the management of a major roofing contracting business and later joining Russell Roof Tiles.
He said the drive to reduce costs can result in individual products being substituted after a roofing specification has already been developed.
“ In today’ s market, the pressure to value engineer projects is very real,” says Scott.“ But swapping elements of a complete roof system for mismatched components may create an apparent saving on paper, while introducing risks that are much harder and more expensive to resolve later.”
According to Scott, the costs associated with rectifying a failed roof can include stripping out defective or incompatible components, replacement products, scaffolding and potential disputes.
BS 8612 sets requirements for Dry Fix roofing systems
The introduction of BS 8612:2018 established performance requirements and testing methods for Dry-Fixed ridge, hip and verge systems used alongside roof slates and tiles.
The standard followed changes to BS 5534, the Code of Practice for Slating and Tiling, which strengthened requirements around mechanical fixing rather than relying solely on mortar.
BS 8612 covers a range of performance requirements for Dry Fix systems, including resistance to wind loading and driving rain and snow, ventilation and durability.
However, Russell Roof Tiles argues that meeting the requirements of the standard does not necessarily mean that every component can be substituted for another product with the same level of confidence.
Two products may both meet the relevant compliance requirements while differing in their materials, design, durability and compatibility with other components in the roof.
The issue is particularly relevant to roofs where multiple products are combined to form the finished system. Roof tiles, ridge and hip products, verge components, underlays, fixings and ventilation products all form part of the roof assembly. Products developed around a particular tile profile may not necessarily provide the same fit or level of weather protection when used with another profile.
This means a substitution that appears relatively minor during
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