uPVC Window Repairs
We Fix the Faults, You Feel the Difference. No upselling, no stress — just honest, practical solutions that extend the life of your windows and protect your property.
At GC Doors, we specialise in professional uPVC window repairs that restore performance, improve comfort, and extend the life of your existing windows—without the need for costly replacements.
Known for being low-maintenance and long-lasting, uPVC windows are a smart choice for homes and businesses alike. But even the most durable systems can suffer over time. Everyday use, shifting frames, weather exposure, and worn mechanisms can all lead to common issues—such as stiff handles, draughty seals, faulty hinges, misted glazing, or windows that simply won’t open or close properly.
We work across a wide range of properties—from small family homes and city flats to large apartment blocks, rental portfolios, schools, and commercial premises. Whether you’re a homeowner, landlord, or property manager, GC Doors delivers high-quality repairs that restore smooth function, improve insulation, and give your windows a second life—efficiently, affordably, and with craftsmanship you can trust.
uPVC Windows
Casement Windows
The UK’s most common uPVC window style
Casement windows are hinged at the side or top and open outward, often with a handle-operated locking system. They’re straightforward and practical, but over time the hinges, friction stays, or locks can wear out—leading to stiff movement, dropped sashes, or poor sealing.
We repair everything from broken handles and jammed hinges to alignment issues that cause draughts. Whether it’s a single opener or part of a larger window unit, we make sure your casement window opens and closes smoothly, locks securely, and seals tightly once agai
Tilt and Turn Windows
Smart and space-saving, but mechanically complex
Tilt-and-turn windows are versatile and popular in modern homes and flats, opening inward either from the top (for ventilation) or fully from the side (for cleaning or escape access). But with that flexibility comes more moving parts—making them prone to locking faults, misalignment, or tilt/turn failures.
Our team is experienced in working with these mechanisms, carefully diagnosing where the issue lies—be it the gearing, hinges, or internal hardware—and restoring full, safe movement without compromising the frame or seal.
Bay and Bow Windows
Multi-panel windows with personality—and unique repair needs
Bay and bow windows curve or angle outward, creating extra interior space and letting in plenty of light. These are often made up of several casement or fixed panels joined together, and they can be particularly prone to alignment issues, glazing failure, or draughts at the joins.
Repairing a bay window requires care and experience—we check each panel individually, reseal joins, re-align opening sashes, and replace any failed hinges or hardware. Our goal is to restore the beauty and function of the entire unit as a whole.
Fixed or Picture Windows
Non-opening windows that frame a view—but still need care
Fixed windows don’t open, but they’re no less important. They let in natural light and contribute to the thermal performance of your home. Common problems include condensation between panes (from failed glazing units), perimeter leaks, or cosmetic damage to the uPVC frame.
We replace blown sealed units, reseal frames where necessary, and provide light refurbishment to restore the clean, bright look of your picture window—without full replacement.
uPVC Window Repairs Services
Practical Solutions for Everyday Problems
Even the most reliable uPVC windows can develop issues over time—from minor annoyances like stiff handles to more disruptive problems like failed locks, draughts, or misted glass. At GC Doors, we’ve seen it all—and fixed it all. Whether it’s one window or an entire property, our team is equipped to tackle a wide range of common faults with precision and care.
We focus on repairing rather than replacing wherever possible, saving you time, money, and unnecessary disruption—while restoring full function, comfort, and security to your space.
🔒 Locking, Handle & Mechanism Failures
If your window won’t close properly, the handle feels loose or the lock won’t engage, we’ll inspect the issue and repair or replace the hardware. We work with all major locking systems and can upgrade parts where needed for improved security and ease of use.
🚪 Stiff, Jammed or Misaligned Openers
Over time, window sashes can become misaligned due to wear, poor installation, or frame movement. This can cause them to stick, jam, or refuse to close properly. We re-align and adjust the hinges and sashes to restore smooth opening and a secure seal.
🌬️ Draughts, Gaps & Poor Insulation
If your uPVC window is letting in cold air, rattling in the wind or showing signs of heat loss, we reseal gaps, replace damaged gaskets or weatherstrips, and make sure your window is fully sealed and energy-efficient again.
🌫 Glazing Issues & Condensation
Condensation inside the glazing (between the panes) usually means the sealed unit has failed. We replace misted or blown double-glazed units w
⚙️ Hinge, Stay & Friction Arm Repairs
Broken or worn friction hinges and stays can affect how securely the window stays open—or prevent it from opening at all. We repair or replace these components to ensure your windows open safely and close tightly.
🧼 Cosmetic Damage & Maintenance
Discoloured frames, minor scuffs, or degraded seals? We offer light cosmetic repairs and frame cleaning to keep your windows looking smart and functioning well, especially for rental properties or before a sale.
Upgrade Options Available
When Repairs Aren’t Enough, We Offer Smarter, Longer-Term Solutions
At GC Doors, we pride ourselves on repairing wherever possible. But there are times when a uPVC window is simply too damaged, inefficient, or outdated for repair to be the best option. In these cases, an upgrade can be a smart investment—improving your property’s comfort, energy efficiency, appearance, and security.
Whether you’re a homeowner looking to future-proof your space or a landlord needing to meet modern standards, we offer a range of tailored upgrade options to suit both residential and commercial properties.
Full uPVC Window Replacement
When the frame is cracked, warped, or structurally compromised—or if multiple hardware failures have occurred—full replacement is often the most practical and cost-effective choice.
We remove the old unit cleanly and install a new uPVC window that matches your property’s aesthetic while meeting modern performance standards.
Glazing Upgrades
If your current windows are fitted with older, inefficient glass, you may benefit from upgrading to high-performance double or triple glazing. This option is ideal for properties with failing sealed units or where improved insulation or noise reduction is a priority.
Professional Sash Window Repair Services in London
Schedule an Inspection
Before starting any job involving the installation, repair, or upgrade of windows and doors, we perform a thorough initial inspection visit. This preliminary step is fundamental to ensuring that each project is executed smoothly and efficiently.
An initial inspection visit provides a critical foundation, allowing us to gather essential information, identify potential issues, and develop a comprehensive plan tailored to your specific needs. Inspection Visits are more than just a formality; they are key to ensuring a well-planned and tailored approach.
Our Customer Promise
Your trust means everything to us — and we work hard to earn it, keep it, and honour it in everything we do. That’s our promise.
At GC Doors, we don’t just supply, install and repair windows and doors — we create experiences that are smooth, reliable, and built on trust. From first enquiry to final sign-off, we’re committed to making your journey with us as straightforward and stress-free as possible.
We understand that every project, whether large or small, represents a meaningful investment. That’s why we treat every customer with respect, listen carefully to your needs, and tailor our approach to meet your goals.
Clear and Honest Communication
We believe in transparency from day one. You’ll always know what to expect — from timelines and pricing to next steps and project updates. We keep you informed at every stage and are always available to answer questions, offer guidance, and provide honest advice.
Professionalism at Every Step
Our team shows up on time, treats your space with care, and works efficiently to get the job done right. We hold ourselves to high standards — not just in our work, but in how we carry ourselves, how we communicate, and how we follow through.
Tailored Advice and Smart Solutions
We take the time to understand your needs and recommend the best products and approaches to suit your space, style and budget. Whether you’re after sleek Sicilian aluminium frames or a reliable repair, we’ll help you make informed decisions with confidence.
Precision and Quality Craftsmanship
Every detail matters. From the accuracy of our measurements to the finish of each installation, we take pride in delivering results that not only look great but perform exceptionally for years to come.
No Surprises – Just Fair, Transparent Pricing
We provide clear, detailed estimates with no hidden costs. We respect your budget and work with you to find the right balance between quality, performance, and affordability.
Ongoing Support and Aftercare
Our service doesn’t end when the job is done. If you have a question, concern, or need support after installation, we’re just a call away. We stand behind our work and are committed to your long-term satisfaction.
Reviews
Leading experts in window and door installation and repairs in London and surrounding areas — but don’t just take our word for it. Read our reviews from satisfied customers who trust us for their window and door installations and repairs. We are committed to providing quality service and ensuring your home or business is secure, functional, and aesthetically enhanced.