When planning a home improvement project, the first and most pressing question for any homeowner is invariably: “How much will it cost?” Replacing an old, draughty door with a secure, energy-efficient double glazed alternative is a significant investment, but the prices can vary wildly. A simple uPVC back door might cost a fraction of what a sprawling set of aluminium bi-fold doors commands.
This comprehensive pillar guide breaks down the average double glazed door costs in the UK for 2026. We explore the pricing for front, back, patio, French, and bi-fold doors, compare the costs of different materials like uPVC, composite, and aluminium, and highlight the hidden factors that can influence your final quote.
Average Double Glazed Door Costs at a Glance
Before diving into the specifics of each door type and material, it is helpful to understand the general price landscape. The table below outlines the average estimated costs for the most common double glazed doors in the UK, including standard installation and VAT. 1
| Door Type | Material | Estimated Cost Range (Fully Installed) |
| Front Door | uPVC | £500 – £900 |
| Front Door | Composite | £900 – £1,500+ |
| Front Door | Timber | £1,200 – £2,500+ |
| Back Door | uPVC (Half-Glazed) | £450 – £800 |
| French Doors | uPVC | £1,200 – £1,800 |
| French Doors | Aluminium | £2,000 – £3,500 |
| Patio Doors (Sliding) | uPVC | £1,000 – £2,000 |
| Patio Doors (Sliding) | Aluminium | £2,000 – £4,000 |
| Bi-Fold Doors (3-Panel) | Aluminium | £3,000 – £5,000+ |
| Bi-Fold Doors (4+ Panel) | Aluminium | £5,000 – £10,000+ |
Note: These figures are indicative averages based on national data for standard sizes. Your actual quote will depend on your specific requirements, location, and the installer you choose.
Front Door Costs: uPVC vs. Composite vs. Timber
Your front door is the focal point of your home’s exterior and its primary defence against intruders and the elements. The material you select is the single biggest factor influencing the cost.
uPVC Front Doors
Unplasticised Polyvinyl Chloride (uPVC) remains the most affordable and popular option in the UK. A standard uPVC front door with double glazed panels typically costs between £500 and £900, fully installed. They offer excellent thermal efficiency, require minimal maintenance, and are available in a variety of colours and finishes, including realistic woodgrain effects. While they may lack the heavy, solid feel of a timber door, modern uPVC doors feature multi-point locking systems that provide robust security.
Composite Front Doors
Composite doors have surged in popularity due to their superior strength, security, and aesthetic appeal. Constructed from a combination of materials — often a solid timber or high-density foam core surrounded by a glass-reinforced plastic (GRP) skin — they mimic the look of traditional wood without the associated maintenance. Because of their complex construction and enhanced durability, composite doors command a higher price, generally ranging from £900 to £1,500 or more for premium designs. 2
Timber Front Doors
For period properties or homeowners seeking a truly authentic, bespoke aesthetic, solid timber front doors are the traditional choice. While undeniably beautiful, they require regular maintenance (sanding, painting, or varnishing) to prevent warping or rotting. High-quality, sustainably sourced timber doors with double glazed panels are a premium product, often starting around £1,200 and reaching well over £2,500 depending on the wood species and craftsmanship.
Back Door Costs: Simple and Secure
Back doors are typically more utilitarian than front doors, focusing primarily on security and allowing light into kitchens or utility rooms. The most common and cost-effective choice is a uPVC back door.
A standard uPVC back door, often featuring a solid lower half and a double glazed upper panel (half-glazed), usually costs between £450 and £800 installed. Fully glazed uPVC back doors, which maximise natural light, sit at the higher end of this spectrum due to the increased volume of toughened or laminated safety glass required. All glass in doors must comply with BS 6206 safety standards, meaning the glass must be either toughened or laminated to prevent dangerous shattering.
Patio and French Door Costs
When opening up a living space to a garden or patio, homeowners typically choose between sliding patio doors and classic French doors. Both are excellent choices, but they suit different architectural styles and practical needs.
French Doors
French doors consist of two side-hinged doors that open outwards or inwards, offering a traditional, elegant aesthetic. They are ideal for smaller openings where sliding doors might be impractical. A standard set of uPVC double glazed French doors generally costs between £1,200 and £1,800 fully installed. Upgrading to aluminium frames — which offer slimmer sightlines and a more contemporary look — will push the price towards £2,000 to £3,500.
Sliding Patio Doors
Sliding patio doors feature large panes of glass that slide horizontally along a track. They are excellent for saving space, as they do not require clearance to swing open, and they offer expansive, uninterrupted views of the garden. A standard two-pane uPVC sliding patio door typically ranges from £1,000 to £2,000 installed. The cost scales upwards as you add more sliding panels or opt for wider expanses of glass.
Bi-Fold Door Costs: The Premium Choice
Bi-fold doors have become the ultimate aspirational home improvement feature. They consist of multiple glass panels that fold back against themselves in a concertina style, effectively removing an entire wall and seamlessly blending indoor and outdoor living spaces.
Due to the complex engineering, heavy-duty tracking systems, and the sheer volume of glass involved, bi-fold doors are the most expensive option. While uPVC bi-folds are available, aluminium is the overwhelmingly preferred material due to its inherent strength, which allows for slimmer frames and larger glass panels. A standard three-panel aluminium bi-fold door system typically starts around £3,000 and can easily exceed £5,000 for larger, bespoke configurations. For expansive four-panel or five-panel systems spanning an entire rear wall, budgets of £7,000 to £10,000+ are not uncommon. 3
5 Key Factors That Affect Your Final Quote
While the averages provide a useful baseline, several specific factors will influence the final quote you receive from an installer.
| Factor | Impact on Cost | Detail |
| Size & Configuration | High | Larger or non-standard sizes require more materials and bespoke manufacturing. |
| Material Choice | High | uPVC < Composite < Aluminium < Premium Timber. |
| Glass Specification | Medium | Toughened, laminated, acoustic, or self-cleaning glass all add a premium. |
| Hardware & Finishes | Medium | Bespoke colours (e.g., Anthracite Grey), premium handles, and smart locks increase cost. |
| Installation Complexity | Variable | Widening an opening, fitting a new lintel, or extensive making good adds significant labour costs. |
Hidden Costs to Watch Out For
When comparing quotes, it is vital to ensure you are comparing like for like. Always check if the quote includes the following potential additional costs before signing a contract.
VAT at 20% should always be explicitly stated in the quote. The removal and legal disposal of your old, heavy door and frame should be included in a comprehensive quote; if it is not, ask about it directly. The process of removing an old frame can sometimes damage surrounding plaster or brickwork, and “making good” these minor damages should ideally be included. Finally, a reputable installer will register the installation with a competent person scheme like FENSA or Certass and provide you with the certificate, usually at no extra charge — but always confirm this upfront.
How to Save Money on Your Double Glazed Doors
While a new door is a significant outlay, there are strategic ways to ensure you get the best value for your money without compromising on quality or security.
The most effective strategy is to gather and compare at least three comprehensive quotes from different installers. This allows you to gauge the local market rate and provides leverage for negotiation. Consider obtaining quotes from both large national companies and smaller, reputable local independent installers, as their pricing structures and overheads often differ considerably.
Additionally, sticking to standard sizes and popular colours (like white uPVC) is generally more cost-effective than ordering bespoke dimensions or custom foiled finishes. Finally, consider the timing of your project; some installers offer seasonal discounts during quieter periods, such as late autumn or early winter, to keep their fitting teams busy.
Key Takeaway: Double glazed door costs in the UK range from approximately £450 for a basic uPVC back door to over £10,000 for a large aluminium bi-fold system. The material, size, glass specification, and installation complexity are the primary cost drivers. Always obtain at least three quotes and ensure they are fully inclusive of VAT, disposal, and certification.