Upgrade your home or building project with our extensive range of doors, bi fold doors and windows at JJ Building Materials. Whether you're replacing internal joinery, improving an entrance, opening a room onto the garden or fitting new windows, our collection brings together products for domestic renovations, extensions, new builds and trade projects. Explore internal doors, external doors, bi fold doors, French doors and uPVC windows, alongside the hardware and accessories needed to complete the job.
With timber, glazed, uPVC and aluminium options available across the range, you can compare products by style, size, finish and specification. We also stock a substantial selection of door accessories, including handles, hinges, closers, door kits, stops, seals and linings, helping homeowners and tradespeople source the main products and finishing components in one place.
Explore Our Doors, Bi Folds & Windows Collections
Internal Doors
Refresh bedrooms, living spaces, hallways and other interiors with our range of internal doors. Choose from different materials, finishes, panel designs and glazed styles, including products from established door manufacturers. Browse our internal doors to compare sizes, designs and individual specifications for your project.
External Doors
Find external doors for entrances, rear access and renovation projects, with timber and uPVC options across the collection. When choosing an exterior door, consider the opening size, material, finish, glazing, security hardware and the manufacturer's stated performance. Explore our external doors to find a suitable option for your property.
Bi Fold Doors
Create a wider connection between indoor and outdoor spaces with our bi fold doors. Our range includes aluminium bi fold door systems in multiple sizes and finishes, giving you options for extensions, kitchens and open-plan living areas. Check the individual product dimensions, configuration, glazing and installation requirements before ordering.
French Doors
French doors provide a classic way to introduce more glazing and create convenient garden or patio access. Browse our French doors to compare available sizes, colours, glazing and handing options, always checking the individual product specification for your opening.
uPVC Windows
Our uPVC windows collection includes a wide choice of sizes, configurations, colours and glazing options for replacement windows and building projects. Consider frame dimensions, opening style, glazing, ventilation and installation requirements when selecting the right window for your property.
Door Accessories & Hardware
Complete your installation with our extensive door accessories range. Shop door handles, door hinges, door closers, door kits, door stops, intumescent and door seals and door linings. Always match hardware to the door type and required specification.
How to Choose the Right Door or Window
Start with accurate measurements and the intended location. Internal doors are generally selected around room style, privacy, glazing and any fire-rating requirements, while external doors need to be suitable for exterior use and should be assessed for security, weather resistance, glazing and thermal performance. For bi fold and French doors, pay particular attention to the complete frame dimensions, opening configuration and handing. When buying windows, check the frame size, opening style, glazing and product-specific installation information.
Do not rely on category-level descriptions alone for technical requirements. Dimensions, fire ratings, glazing, thermal values, handing and supplied components can vary between products, so check the individual product specification and manufacturer guidance before ordering or installation.
Why Buy Doors & Windows from JJ Building Materials?
- Extensive range of internal and external doors
- Aluminium bi fold doors and uPVC French doors
- uPVC windows in multiple sizes and configurations
- Hundreds of door hardware and accessory options
- Products from recognised door and window manufacturers
- Options for homeowners, builders and renovation projects
- UK delivery across a wide range of products
Frequently Asked Questions
How do I choose the right size internal door?
Measure the existing opening and check the door width, height and thickness required. If you're replacing an existing door, measure it as well as the frame or lining and compare those dimensions with the individual product specification.
What should I look for when buying an external door?
Consider the material, dimensions, finish, glazing, security hardware, weather suitability and thermal information provided for the individual product. Also check whether the product is supplied as a door slab or complete doorset.
What are the benefits of bi fold doors?
Bi fold doors can create a large glazed opening and a strong connection between indoor and outdoor areas. Their suitability depends on the opening, configuration and product specification, so check dimensions, glazing and installation requirements carefully.
What is the difference between bi fold doors and French doors?
French doors normally use two hinged door leaves, while bi fold systems use multiple panels that fold together to create a wider opening. The best choice depends on the available opening, layout, preferred appearance and budget.
Are uPVC windows a good choice for replacement windows?
uPVC windows are widely used for replacement and new-build projects because they are practical and available in many sizes and configurations. Compare the glazing, opening style, colour and individual performance information before choosing a window.
Can I buy door handles and hinges separately?
Yes. JJ Building Materials stocks dedicated collections for door handles, hinges and other door hardware, allowing you to select components separately where appropriate for the door and installation.
Do fire doors need special hinges and seals?
Fire-rated doors must be installed as part of a compliant assembly using suitable components. Check the door manufacturer's requirements for hinges, intumescent seals, closers and other hardware, and follow applicable building requirements.
How do I know which way a door or window opens?
Check the handing and configuration stated on the individual product page. Terminology can vary between products, so use the manufacturer's diagrams or documentation where supplied rather than assuming the opening direction.
Should I measure the structural opening or the frame?
This depends on the product. Some dimensions describe the door or window itself while others describe a complete frame or doorset. Always check the manufacturer's sizing information before ordering.
Can I match doors and windows across a project?
Often you can coordinate colours and styles, particularly across grey, white, timber and glazed products. Exact shades and finishes can vary by manufacturer, so compare product information when visual matching is important.
Doors & Windows Buying Guides
Use our buying guides to compare the main options, understand the measurements and specifications to check, and choose products that suit your project.
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