Chimney flashing tapes in practice
Chimney flashing is one of the most critical elements of the entire roof covering. It is around the chimney that leaks, moisture penetration into the thermal insulation, and damage to the roof structure most frequently occur. For this reason, it is essential to use appropriate sealing materials and ensure that all connections are executed correctly.
Modern chimney flashing products, such as Eurovent® FLEX EPDM, Eurovent® FLEX EPDM Q, and the Eurovent® FLEX LINE chimney flashing strip, enable fast and reliable sealing of the junction between the chimney and the roof surface, regardless of the chimney shape or the type of roof covering.
Why is chimney flashing so demanding?
Chimneys, dormers, and roof-to-wall junctions are areas with an increased risk of leaks and water penetration. This is due to several factors:
- different thermal expansion of materials (bitumen membranes, metal sheets, brick, ceramics, EPDM),
- the continuous movement of the roof structure caused by wind loads and temperature fluctuations,
- complex geometry, which requires flexible and adaptable sealing solutions,
- high exposure to rainwater and snow runoff flowing down the roof slope.
For these reasons, traditional metal flashing is increasingly supplemented or replaced with modern technical sealing tapes, which offer high flexibility, strong adhesion and reliable long-term sealing performance.
Structure of modern chimney flashing tapes
Eurovent® chimney flashing tapes feature a multi-layer construction designed to ensure durability and ease of installation:
- Flexible EPDM layer – resistant to UV radiation, stretching and extreme temperatures,
- Aluminium or synthetic mesh reinforcement – facilitates precise shaping of the tape around the chimney,
- Strong butyl adhesive layer – ensures secure, watertight adhesion to most substrates,
- Silicone release liner – protects the adhesive layer until installation.
The Eurovent® FLEX EPDM Q version additionally features a profiled structure, which speeds up installation on the roof slope and improves the overall appearance of the finished flashing.
Benefits of using Eurovent® chimney flashing tapes
- Watertight sealing – effectively protects against the penetration of water, snow and moisture.
- Flexibility and adaptability – ideal for chimneys, roof windows and dormers.
- Easy handling – can be quickly shaped even around complex roof covering edges.
- Weather resistance – EPDM does not crack, crumble or lose its elasticity over time.
- Fast installation – suitable for both new roof installations and the renovation of existing flashings.
Principles of proper chimney flashing installation
For chimney flashing tape to perform effectively, several key installation rules must be followed:
1. Proper substrate preparation
The chimney surface must be dry, stable, and free from dust, debris and loose particles before installation.
2. Correct installation sequence (from bottom to top)
- first the bottom flashing,
- then the side flashings,
- finally the top flashing, overlapping the previous sections.
This sequence ensures natural water runoff along the roof slope and prevents water from penetrating under the flashing.
3. Careful application and shaping of the tape
The tape should fit tightly to both the roof covering and the chimney walls. Any cavity or gap may become a potential leakage point. The aluminium mesh reinforcement used in FLEX EPDM tapes facilitates shaping the tape even around uneven surfaces.
4. Firm pressure on the butyl adhesive layer
The butyl adhesive is activated by pressure, which is essential to achieve a fully watertight bond.
5. Securing the upper edge
The final step is to seal the upper edge of the flashing using a profile, termination bar or sealing compound to prevent water from penetrating behind the tape.
Proper chimney flashing is the foundation of a durable and reliable roof system. The use of Eurovent® chimney flashing tapes significantly simplifies this process while ensuring a high level of watertightness and resistance to weather conditions. It is a solution that combines modern technology with practical ease of installation, providing effective protection against one of the most common causes of roof failures.
