IL Gas Vent System Parts
For all your IL Gas Vent System installation and maintenance needs, BES stocks a complete range of genuine SFL® IL components designed for safe, efficient, and reliable gas venting. From straight pipes and elbows to flue boxes, adaptors, and terminals, every part is precision-made for quick, secure installation and long-lasting performance.
Shop for SFL® IL Gas Vent System components at BES today for great offers and benefit from free next-day delivery on qualifying orders.
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Explore Our Comprehensive Range Of IL Gas Vent System Products
BES offers every major component of the IL Gas Vent System, ensuring seamless integration across installations.
SFL® IL Straight Length Pipes
Straight length vent pipes form the backbone of any IL flue system. Available in 125mm and 150mm diameters and lengths ranging from 152mm up to 1524mm, they allow installers to achieve the correct overall flue height and draught. Constructed from an aluminium inner liner with an outer steel casing, they provide both strength and corrosion resistance.
SFL® IL Flue Boxes
IL Flue Boxes provide secure housing for gas fire installations. The SFL® IL Recessed Flue Box – 125mm is designed for built-in applications, while the Freestanding Flue Box offers flexibility for various installations.
SFL® IL Adaptors to Flexible Liners & IL Flue Adaptors
BES stocks a full range of IL adaptors to connect your system seamlessly. Options include:
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IL to B Vent Adaptors – for linking IL systems with B Vent.
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IL to Flexible Liner Adaptors – available in 125mm and 150mm.
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Flexible Liner to IL Adaptors – also available in 125mm and 150mm, allowing flexible liners to connect securely back into IL systems.
SFL® IL Adjustable Elbows
The IL Adjustable Elbows available at BES offer flexibility in routing vent systems around obstacles. The 125mm and 150mm versions allow for smooth directional changes, ensuring optimal performance and alignment.
SFL® IL Adjustable Straight Length Pipes
Our IL Adjustable Straight Length Pipes provide precise length adjustments for a perfect fit. The 457mm and 305mm models, available in both 125mm and 150mm diameters, ensure compatibility with a range of installation needs.
SFL® IL Connectors
IL Connectors, such as the Draught Hood Connector – 125mm and Draught Hood Connector – 150mm, facilitate secure connections between gas appliances and the flue system, ensuring proper ventilation and safety.
SFL® IL Firestop Spacers
Essential for safety, our IL Firestop Spacers maintain the integrity of fire-rated structures by providing safe clearances around flue penetrations. The 125mm and 150mm options prevent heat transfer, ensuring compliance with safety regulations.
SFL® IL Flashing
Our adjustable IL Flashing models accommodate pitches from 5° to 30°, while tall cone flat flashings offer alternative weatherproofing solutions.
SFL® IL Ridge Tile Adaptors
The IL Ridge Tile Adaptors in our range offer a secure exit point for venting through ridge tiles. The SFL® IL Ridge Tile Adaptor – 125mm provides a reliable connection, ensuring proper airflow and weather resistance.
SFL® IL Storm Collars
With IL Storm Collars preventing water from entering the flue system at roof penetration points, they are an essential component of the IL gas vent system. The 125mm and 150mm options work in conjunction with flashing to provide complete weather protection.
SFL® IL Support Plates
IL Support Plates provide a stable base for vertical venting. The 125mm and 150mm versions ensure a secure and level installation, reducing strain on the flue system.
SFL® IL Tees
BES stocks a complete selection of IL Tees to cover all branching needs:
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90° Equal Tees with Caps – in 125mm and 150mm.
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135° Equal Tees with Caps – in 125mm and 150mm.
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Branch Reduced Tee – 150mm x 125mm for mixed-diameter connections.
These allow installers to branch off safely while maintaining system performance and integrity.
SFL® IL Tee Caps
Tee Caps securely close off unused tee connections while maintaining system integrity. The 125mm and 150mm versions provide a secure fit for capped-off sections.
SFL® IL Terminals
The SFL® IL Fabricated Aluminium Terminals (125mm and 150mm) provide a durable, weather-resistant termination point for the flue system. Built for long-term performance, these terminals ensure safe discharge of combustion gases while protecting against rain and debris ingress.
SFL® IL Wall Bands
Wall bands secure the flue system to walls, providing stability and alignment. BES stocks both standard wall bands for close-to-wall installations and stand-off wall bands for applications requiring additional clearance. Available in 125mm and 150mm sizes, they offer reliable support in different installation environments.
How Does An IL Gas Vent System Work?
The SFL® IL Gas Vent System is a factory-made, twin-wall flue system with an insulating air gap. Designed for natural draft gas appliances operating up to 250°C, it safely removes combustion gases from appliances such as boilers, gas fires, and water heaters. The twin-wall design keeps the outer casing cooler, improving safety and reducing clearance requirements.
IL systems are used in both domestic and light commercial settings and are recognised for their durability, easy assembly, and compliance with UK Building Regulations.
Why Choose BES
At BES, we recognise the importance of high-quality flue systems for ensuring safe and efficient operation of gas appliances. That’s why we offer only the best IL gas vent components from SFL® and also a wide range of alternatives - browse our complete range of flue system products here.
Our reputation is built on trust and service, so when you shop with us, you’ll benefit from premium-quality products at competitive prices and the support of our knowledgeable team, who are always ready to assist with any technical queries or product recommendations.
Here To Help
With BES, you can be confident that you’re getting the best value, best service, and best products for your IL Gas Vent System project. Shop online for fast delivery or get in touch if you need help selecting the right product for your project or if you can’t find a specific part.
IL Gas Vent Systems FAQs
What is an IL Gas Vent System?
An IL Gas Vent System is a twin-wall, insulated flue designed for draught-hooded gas appliances with flue gas temperatures up to 250°C.
What pipe sizes are available?
BES stocks IL Gas Vent Pipes in 125mm and 150mm diameters, with lengths from 152mm up to 1524mm. Adjustable lengths are also available.
How do I choose the right length of vent pipe?
When calculating total height, always match the appliance outlet size and consider the required minimum flue height for correct draught performance. Adjustable lengths help fine-tune installations.
What’s the difference between standard and stand-off wall bands?
Standard wall bands hold the flue close to the wall. Stand-off wall bands provide additional clearance, useful for uneven walls or where extra spacing is required.
Can IL systems be used with LPG as well as natural gas?
Yes. IL systems are suitable for both natural gas and LPG appliances, provided the appliance is draught-hooded and within the system’s operating limits.
What are IL Flue Terminals made from?
IL Flue Terminals at BES are fabricated from aluminium, providing a durable, corrosion-resistant, and weatherproof finish that allows gases to discharge freely while preventing rain ingress.
When would I use a 90° vs 135° tee?
90° tees are standard for branching; 135° tees provide smoother airflow, which can improve draught. Reduced branch tees allow mixed-diameter connections.
What is the purpose of firestop spacers and support plates?
Firestop spacers ensure safe clearances when the flue passes through walls, ceilings, or floors, maintaining the integrity of fire-rated structures. Support plates provide a secure base for vertical vent runs, helping distribute system weight.
What are alternatives to IL Gas Vent Systems?
Alternatives include B Vent systems (also twin-wall but different spec), direct vent systems, and power vent systems with fans. IL is most often chosen for traditional draught-hooded appliances needing vertical venting.