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MPN: GX150/90B

Estimated Delivery: 3 - 5 Working Days

Grant Extension 150mm Black

Grant Extension 150mm Black


Regular price £74.75 Excl. VAT
£89.70 Incl. VAT
Sale price £74.75 Excl. VAT
£89.70 Incl. VAT
Regular price
*For business & Trade Accounts only.
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Key Information

Product Information

Grant Extension 150mm Black

The Grant Extension 150mm Black is designed to provide additional flexibility when installing compatible Grant external boiler flue systems. Supplied as part of a modular flue arrangement, it can be used to extend suitable starter kits and help installers create a flue configuration that works with the specific requirements of the property. Available for compatible boiler output ranges of 12-26kW and 26-70kW, this extension provides a practical option for different external boiler installations.

Modular Flue System

The Grant system is supplied in modular form, helping accommodate a wide variety of installation layouts. Short starter kits are available in lengths of approximately 270-350mm, while standard starter kits are available from approximately 370-550mm. The 150mm extension can be incorporated into a compatible arrangement where additional flue length is required.

Flexible Installation Options

Compatible extensions and elbows from the Yellow System low-level balanced flue range can be used to extend suitable starter kits. This provides installers with greater flexibility when adapting the flue route. Where required, a plume diverter can also be used to convert an existing Yellow System low-level flue into an external high-level or vertical arrangement, subject to compatibility and installation requirements.

Creating Flue Offsets

The system can be configured to create offsets in straight flue runs using compatible 45-degree elbows and extensions. This can be particularly useful when the flue needs to be routed around building features or other obstacles.

Available Boiler Output Variants

The Grant Extension 150mm Black is listed for two boiler output ranges: 12-26kW and 26-70kW. This allows the appropriate version to be selected according to the output of the compatible Grant boiler and the requirements of the flue installation.

Key Features

  • 150mm flue extension
  • Black finish
  • Available for 12-26kW and 26-70kW boiler output ranges
  • Supplied as part of a modular flue system
  • Designed to accommodate a wide range of installation layouts
  • Short starter kits available from approximately 270-350mm
  • Standard starter kits available from approximately 370-550mm
  • Compatible extensions and elbows available from the Yellow System low-level balanced range
  • Can be used with suitable plume diverter arrangements
  • 45-degree elbows and extensions can be used to create offsets
  • Designed to provide additional flue length where required

Frequently Asked Questions

What boiler output ranges is the Grant 150mm Extension available for?

The extension is listed for compatible boiler output ranges of 12-26kW and 26-70kW. The correct variant should be selected to match the boiler and flue system being installed.

Can the Grant 150mm Extension be used to create a flue offset?

Yes. Compatible 45-degree elbows and extensions can be used with the modular system to create offsets in straight flue runs, helping installers route the flue around obstacles.

Can the Grant system be converted from low-level to high-level or vertical flue?

A suitable plume diverter can be used to convert an existing Yellow System low-level flue to an external high-level or vertical arrangement, provided the complete configuration is compatible and installed according to the manufacturer's requirements.

Why Choose Us

At JJ Building Materials, we're committed to supplying quality building products at competitive prices, backed by the service and expertise you'd expect from an established independent merchant. Whether you're a trade professional managing large-scale projects or a homeowner taking on a DIY renovation, we're here to help you find the right products for the job.

As part of the JJ Roofing Supplies Group, we build on decades of experience supplying construction materials across the UK. We've expanded beyond roofing to offer a growing range of building materials, including timber, insulation, landscaping products, plumbing supplies, flooring, doors, bricks, fencing, garden buildings and much more – all available to order online with nationwide delivery.

We work with many of the industry's leading manufacturers to bring you trusted products that meet the highest standards of quality and performance. Our team is passionate about providing excellent customer service, competitive pricing and a straightforward shopping experience from start to finish.

When you shop with JJ Building Materials, you can expect:

  • Competitive prices on leading brands and quality products.
  • Nationwide delivery across the UK
  • A constantly expanding range of building and landscaping materials.
  • Friendly, knowledgeable customer support.
  • A trusted business backed by the JJ Roofing Supplies Group.

Delivery

Every order is personally reviewed by our experienced team to ensure everything is correct before dispatch. We offer delivery from as little as the next working day on selected products, so please refer to the dark blue Estimated Delivery box above for the expected delivery timeframe for this item.

We work with trusted manufacturers and specialist delivery partners to ensure your order arrives safely and on time. You'll receive tracking details once your order has been dispatched, and if we need to confirm any delivery details, one of our team will contact you directly to keep everything running smoothly.

Roof Tiles & Fittings:

We recommend ordering an additional 10% of roof tiles to allow for any breakages that may occur during delivery or handling. Roof tiles are naturally fragile, and having a few extra on site helps prevent delays and ensures your roofing project can be completed without interruption.

Multiple Products from the Same Supplier

If you're ordering multiple products from the same supplier, your order will be dispatched together once all items are ready. This means the longest lead time will apply.

If you need part of your order sooner, please call us on 01202 113233. We can arrange a split delivery, although an additional shipping charge will apply.

Grant Extension 150mm Black

£74.75

Can I collect this product from a local branch?

Absolutely. Check availability at your nearest branch during checkout or contact us directly.

Do you offer bulk pricing or trade discounts?

Yes, we offer competitive rates for trade customers and bulk orders. Contact our team for a tailored quote.

What if the product arrives damaged?

Please notify us within 48 hours of delivery. We’ll arrange a prompt replacement or refund as needed.

How fast is the delivery time?

Most items are delivered within 2–5 working days, depending on stock and location. Some products may take longer times.

What is the Return Policy?

We accept most returns within 14 days of delivery, provided the items are unused, in their original packaging, and in resalable condition. Please contact our customer service team to arrange a return or discuss any concerns.