Roof penetrations

How a roof penetration works

A roof penetration is used to safely route ventilation ducts, exhaust air, air intake, cable or technical services through the roof structure without compromising the building envelope.

Typical applications:

• Roof penetration for ventilation and residential ventilation

• Exhaust air and air intake for mechanical ventilation systems

• Roof penetration for cable, solar panels and technical installations

• Roof penetration for flat roofs, bitumen roofing and fibre cement

• Connection of roof fans and roof cowls

Incorrect dimensioning or improper installation may result in moisture, thermal bridges, condensation and air leakage.

Materials, construction and function

Roof penetrations are designed to withstand:

• Rain, snow and wind exposure

• Temperature fluctuations and ultraviolet radiation

• Negative and positive pressure from ventilation systems

Common materials:

• Galvanised, stainless or coated steel

• Impact resistant plastic and composite materials

• Insulated constructions to prevent condensation

An insulated roof penetration is particularly recommended for residential ventilation and heat recovery systems, where temperature differences may otherwise cause moisture formation within the roof structure.

Lindab roof penetrations – practical modular construction

These roof penetrations provide precise and airtight joints with full compatibility across Lindab ventilation systems.

Popular series and designations:

• Lindab TGF / TGFV

Advantages of Lindab roof penetrations:

• Modular system enabling easy installation

• Documented airtightness and robust construction with limited maintenance requirements

• Suitable for both flat and pitched roof ridges

• Compatible with Lindab duct systems including SR pipes and roof cowls

Note that the TGFMF pipe is sealed at the factory. Always inspect the joint for transport or handling damage and recheck it after installation. Wind and water exposure may cause sealant fatigue, which is why inspections should be carried out at intervals of no more than eighteen months.

Exhausto TGR products and roof ventilation

Exhausto supplies proven solutions for both residential and commercial ventilation systems.

The range includes:

• Exhausto roof penetrations

• Exhausto THAV roof cowls and TGK

• Solutions for Exhausto roof fans and residential ventilation

The penetrations are developed to ensure:

• Safe routing of exhaust air and intake air

• Stable operation when combined with roof fans

• Seamless integration with existing Exhausto ventilation systems

TGK roof penetrations – robust and insulated solution for roof ventilation

TGK roof penetrations are square units where functionality and aesthetics are combined when ventilation ducts are routed safely through the roof structure. TGK is designed for use with Exhausto DTH and DTV roof fans, where the roof penetration and fan are installed as one integrated solution.

The core of the TGK construction consists of a multilayer structure with robust galvanised steel sheet, a 50 mm mineral wool insulation layer and an internal perforated liner. Together these elements provide effective thermal insulation and sound attenuation.

TGK roof penetrations are available in several standard sizes and lengths, allowing adaptation to different ventilation capacities and roof pitches. They are typically supplied with weather resistant PERFORM flashing and can be adjusted to the roof pitch. Alternatively, zinc or project specific flashings can be supplied.

TGK also features an integrated cable duct, allowing cable installations to pass through the roof surface without additional cut-outs or sealing work. Optional accessories include overpressure dampers and support brackets to provide enhanced stability, particularly in larger ventilation systems.

Systemair roof penetrations – compatible with TFSR

With Systemair ventilation you gain access to flexible and internationally proven solutions.

We supply roof penetrations, including RTG, that are compatible with Systemair TFSR roof fans, making them suitable for:

• Commercial buildings and technical installations

• Residential ventilation systems with high airflow capacity

• Projects focusing on standardisation and operational reliability

RTG cable roof penetrations

RTG roof penetrations from Systemair are designed for use with Systemair TFSR roof fans. The focus is on easy installation, reliable operation and a visually integrated result.

The construction is sound and condensation insulated, reducing noise transmission and condensation formation in the roof structure. This is especially important in applications with continuous operation and high airflow volumes. RTG is supplied as standard in black powder coated steel, providing a finish that matches modern roof solutions and ventilation installations.

To simplify installation, RTG includes integrated cable routing, allowing electrical connections to the roof fan to be led gently and discreetly through the roof penetration. The supplied telescopic support ensures stable fixing and allows adaptation to different roof constructions and insulation thicknesses.

RTG roof penetrations are supplied with separate flashing, which is installed after the roof penetration itself has been fixed to the roof. Available options include:

• SabetoFlex flashing that can be shaped to match the roof structure

• Black powder coated steel flashing suitable for bitumen roofing and flat roof surfaces

The roof penetration is available in lengths of 900 or 1200 mm. Both steel and flexible flashings can be supplied adapted to specific roof pitch ranges, ensuring airtightness and correct water drainage under varying roof conditions. RTG complies with Fire Standard DS 428:2019 and the requirements of BR18.

Roof penetrations for bitumen roofing, solar panels and cable

We supply specialised solutions for:

• Roof penetration for bitumen roofing with airtight solutions for flat roofs

• JUAL roof penetrations including solutions such as stainless steel flanges, penetrations with over-membrane for pitched roofs and 50 mm single layer bitumen cable penetrations

• Roof penetration for solar panels and cable

• Universal roof penetration and DAFA cable collars for varying roof types

These solutions are commonly used in:

• Domestic and industrial solar panel installations

• Technical installations and large cable routing systems

• Combined ventilation and electrical installations

Correct selection ensures that both the roof membrane and the installation remain airtight throughout the service life of the building.

Installation – important considerations

For a durable and reliable result you should always:

• Match the roof penetration to the roof type and pitch

• Ensure correct fixing and flashing

• Use insulated solutions where heat or cold transfer is present

• Follow the manufacturer installation instructions

For installers and procurement professionals it is essential to select system compatible solutions, ensuring that roof penetration, roof fan and roof cowl function optimally together.

Roof penetrations for professionals and private users

Whether you are:

• A private homeowner

• A ventilation installer

• A consultant or procurement professional

• A contractor working on European projects

you will find high quality roof penetrations here that comply with current requirements for ventilation, airtightness and durability.

If you need guidance when selecting a Lindab, Exhausto or Systemair roof penetration, please contact us at info@bels.dk or complete the contact form. You will receive a response within 24 hours.