VELUX CFU & ISU Fixed Flat Roof Rooflight (Package)

VELUX CFU & ISU Fixed Flat Roof Rooflight

The VELUX CFU & ISU Fixed Flat Roof Rooflight is a beautifully designed glazing solution that transforms flat roof spaces by bringing in an abundance of natural daylight. Perfect for brightening living areas, extensions, offices, or commercial spaces, this rooflight delivers a clean, modern look with exceptional energy efficiency and long-lasting performance. The CFU base unit combined with the ISU fixed flat glass top unit creates a sleek and minimalist appearance, both inside and out. The frameless internal design allows uninterrupted views of the sky, while the flat, toughened glass exterior ensures a stylish, low-profile finish that blends seamlessly with any modern roofline. Engineered for durability and thermal performance, the VELUX CFU & ISU system features high-quality double or triple glazing options to reduce heat loss and minimize external noise. The innovative design also prevents condensation build-up and ensures excellent drainage — keeping your rooflight crystal clear and functional all year round. With its easy installation and premium materials, this fixed flat roof window is the perfect combination of aesthetic appeal, energy efficiency, and reliability — a hallmark of VELUX craftsmanship.

Key Benefits

• Maximum daylight: Fixed flat glass design allows light to flood interior spaces. • Sleek appearance: Frameless interior and low-profile exterior for a modern finish. • Energy efficient: Double or triple glazing reduces heat loss and improves comfort. • Weather resistant: Toughened glass and superior seals ensure long-term durability. • Low maintenance: Designed to resist condensation and easy to keep clean. • VELUX reliability: Backed by years of trusted engineering and design expertise.

Typical Applications

• Flat roofs on residential or commercial properties • Kitchen extensions and living room spaces • Offices, stairwells, and hallways requiring more natural light • Renovations or new build projects needing a modern rooflight solution ________________________________________

Specifications

• Product Name: VELUX CFU & ISU Fixed Flat Roof Rooflight • Type: Fixed (non-opening) flat roof window • Base Unit: CFU (composite base frame) • Glazing Unit: ISU (flat glass top) • Glazing Options: Double or triple glazing available • Operation: Fixed (no ventilation) • Frame Material: Maintenance-free PVC • Glass Type: Toughened outer glass, laminated inner pane

FAQs

Is the VELUX CFU & ISU Rooflight suitable for all flat roof types?

Yes. It is compatible with most flat roof materials, including single-ply membranes, bitumen, and GRP systems. Always ensure the installation is carried out according to VELUX guidelines for best results.

Can the rooflight be opened for ventilation?

No. This version is a fixed unit, meaning it does not open. If you require ventilation, VELUX also offers opening versions such as the **VELUX CVU** model.

Does the rooflight provide good insulation and noise reduction?

Yes. The CFU & ISU system is designed with high-performance double or triple glazing to deliver excellent thermal insulation and significantly reduce external noise.

Check out our other products here.

Explore more from our range here.

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.
  

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.