A roof penetration is a component that passes through one or more functional layers of the roof, such as a vent pipe, chimney, cable, support or outlet. Every penetration must be connected in a way that keeps water flow, airtightness, thermal protection and movements under control.
What is a penetration? Function and classification
Penetrations bring together several interfaces in a confined space and are therefore among the roof details prone to damage. Secure integration is more important than the visible cover piece alone.
Practical use
Positions and distances are planned as early as possible. The load-bearing structure, airtight layer, insulation, underlay or waterproofing and outer cover are then each connected in accordance with their respective systems.
Designs and construction variants
Depending on the roof type, moulded parts, collars, bonding flanges, junction flashings or liquid-applied resins are used. Round, angular, movable and multipart penetrations require different details.
What should be considered in practice?
Insufficient distances between details, unsuitable substrates and uncoordinated materials make reliable execution more difficult. Retrofitted penetrations should not be improvised.
Current technology and development
More densely occupied roofs with photovoltaics and building services increase the need for grouped, maintainable pass-throughs and coordinated detail planning.