uPVC Windows
Supply Only | Supply & Fit
uPVC windows are a practical, energy-efficient, and cost-effective solution for UK homes. At Colin’s Sash Windows, we specialise in uPVC windows, while also supplying high-quality sash, casement, and flush styles to suit a wide range of property types.
Our uPVC windows are designed to deliver strong thermal performance, enhanced security, and long-term durability, without the ongoing maintenance associated with timber alternatives.
What are uPVC Windows?
uPVC (unplasticised polyvinyl chloride) is a rigid, weather-resistant material widely used for modern window frames. It does not rot, swell, or corrode, making it ideal for the UK climate.
Our uPVC windows are manufactured using modern multi-chambered profiles and paired with double glazing, allowing them to achieve excellent insulation, draught reduction, and long service life.
Our modern uPVC Windows Styles
Our modern uPVC windows come in a variety of styles to suit every home and preference, including uPVC sash windows, uPVC casement windows, flush casement windows, Ecoslide uPVC vertical sliding sash windows, and mechanically jointed uPVC sash windows. Each style delivers unique benefits in performance, design versatility, and low-maintenance durability.
Below is a quick overview of the types of custom uPVC windows we offer 👇
uPVC Sliding Sash Windows
uPVC sliding sash windows are the core focus at Colin’s Sash Windows. They replicate the traditional appearance of timber sash windows while offering the performance advantages of modern materials.
uPVC Casement Windows
uPVC casement windows are a versatile and widely used option. Hinged at the side and opening outward, they provide excellent ventilation and a strong seal when closed.
uPVC Flush Windows
Flush uPVC windows sit level with the outer frame, creating a clean, contemporary appearance. They combine minimalist design with the same energy efficiency and security benefits as other uPVC styles.
ECOslide Sash Windows
These functional eco-sliders are an excellent choice for home renovations. With Ecoslide vertical sliding sash windows, you get authentic Victorian charm plus advanced benefits like robust security, superior thermal insulation, and noise reduction
Mechanically Jointed uPVC Sash Windows
Our double-glazed, mechanically jointed uPVC sash windows authentically replicate the traditional 90-degree joints of timber sliding sash windows, making them suitable for conservation areas and fully compliant with UK Building Regulations.
Secondary & Decorative Glazing
In addition to our uPVC windows, at Colin’s Sash Windows we also offer the secondary glazing for listed buildings and conservative areas replacement windows is not permitted. And with this we also offer the decorative glazing with the different options available in obscure glass to enhance privacy and coloured glass to make your home more charming and colorful.
Security & Safety Standards
Security is built into every one of our uPVC windows we supply.
Colours, Finishes & Hardware Options
Our uPVC windows are available in a wide range of colours and finishes to suit both traditional and modern properties.
Popular coloured upvc windows options include: White, Anthracite Grey, Chartwell Green, Woodgrain finishes such as oak and rosewood, or Dual-colour foils (different internal and external colours).
You can also choose from a variety of hardware options to match your preferred style, including lift Hooks, Pole Eyes, Locking Systems, Tilt Mechanism, Travel Restrictors, D handle, & Sash Knob.
uPVC Sash Windows Colors Options
Casement Windows Colors Options
uPVC Windows
BFRC Energy Rating Comparison
The British Fenestration Rating Council (BFRC) rates windows using an A++ to G scale.
Our double glazed uPVC windows achieve competitive ratings. All our uPVC windows are independently tested by BFRC and rated afterward. The purpose of this information is that you should know about energy efficiency before replacing or buying new windows. Check the windows energy effciecy ratings below.
| Window Material | Typical BFRC Rating* | Typical U-Value (W/m²K) | Performance Notes |
|---|---|---|---|
| uPVC | A – A+ | ≈ 1.2 – 1.4 | Multi-chambered uPVC profiles with Argon-filled double glazing and Low-E glass usually deliver the best overall insulation and energy efficiency. |
| Timber (Wooden) | B – A | ≈ 1.3 – 1.5 | Timber is naturally insulating and ideal for conservation and period properties. Performance depends on timber thickness, glazing specification and external paint or stain finish. |
| Aluminium | B | ≈ 1.4 – 1.6 | Modern aluminium frames use thermal breaks to achieve good U-values. Slim sightlines maximise glass area and light while still meeting current energy-efficiency standards. |
*Typical ratings shown for modern double glazed specifications. Exact BFRC ratings and U-values depend on final glass, spacer and frame configuration chosen for your project.
Why Choose our uPVC Windows for Your Home?
uPVC windows remain the most popular window choice in the UK because they balance performance, affordability, and longevity.
Energy Efficiency & Thermal Insulation
Our uPVC windows are designed to reduce heat loss, improve indoor comfort, and support compliance with UK Building Regulations (Part L). Double glazing, warm-edge spacer bars, and tightly sealed frames all contribute to improved thermal performance.
Low Maintenance & Long Lifespan
Unlike timber windows, uPVC windows do not require painting or sealing. A simple cleaning keeps them looking good and functioning properly for years.
Noise Reduction
Double-glazed uPVC windows help reduce external noise, improving comfort in busy or urban environments.
Cost-Effective Replacement Solution
uPVC windows offer excellent value compared to timber or aluminium, making them a popular choice for full or partial window replacement projects.
To Get Value For Money
Choose Colin's Sash Windows
10 Years Gaurantee
All our modern uPVC windows comes with the 10 years on parts and labour.
Made in Britain
We supply only made in Britain uPVC windows that are manufactured in UK.
We Match Your Price
If you have got a cheaper price from any other supplier then we are ready to match the price.
Our Verified Customer Reviews ✅
We went for their uPVC sliding sash windows to replace the old ones. The price was unbeatable for A+ rated double glazing.
we used their recommended fitter, and the finish is excellent.
Highly recommend without the premium price tag.
How Much Do uPVC Windows Cost?
Looking for the cheapest uPVC windows online? Pricing depends on several factors, including style, size, glazing, and finish.
- Supply-only uPVC sliding sash windows typically start from around £270 + VAT for white finishes.
- Woodgrain or specialty finishes are priced higher due to additional manufacturing steps.
- Lead times usually range from 3–6 weeks depending on colour and specification.
We also offer supply and fitting options, with installation costs varying depending on access, window type, and project size.
For the most accurate pricing, we recommend requesting a tailored quote based on your exact requirements.
How Much Can You Save With
our Double glazed uPVC Windows?
Our uPVC double-glazed windows can significantly reduce heat loss, helping to lower heating bills over time. According to the Energy Saving Trust, upgrading from single-glazed windows to A-rated double glazing in a typical semi-detached home can save around £140 per year on energy bills. For higher-efficiency options or larger properties, savings can reach up to £235 annually, depending on the existing windows and home type.
Savings vary based on:
- Existing window condition
- Property size and type
- Glazing performance
- Household energy usage and location
Over the 20–35 year lifespan of quality uPVC windows, these annual savings often total thousands of pounds, with a typical payback period of 8–15 years through energy reductions alone.
Calculate the Cost of uPVC Windows Online
Get a fast, accurate estimate modern uPVC windows in just 60 seconds using our double glazing cost calculator. No sign-up, no obligation – simply enter your details and see your tailored price.
Benefits Of Buying
uPVC Windows Online From Us
Choosing our double glazed windows means more than simply upgrading your home, it means gaining the complete support, quality, and reassurance that come with Colin’s Sash Windows. We focus on building lasting trust with every customer, which is why our products and service standards are designed to deliver real value and stand apart from typical suppliers.
Energy Efficiency
Our uPVC windows are built with advanced thermal technology, including Low-E coated glass, argon gas filling, and warm edge spacer bars. Together, these features enhance insulation and minimize heat loss, helping most window configurations achieve U-values between 1.2 and 1.4 W/m²K. The result is a warmer interior and reduced energy bills when compared with single glazing.
Security
Our uPVC window units are designed for dependable security, featuring tough double glazed panes and reinforced uPVC frames that help resist forced entry. Multi-point locking comes as standard, with PAS 24 compliant hardware available for new build specifications. This combination delivers reliable, long lasting protection for your home.
Condensation Control
Low-E glass, argon-filled cavities, and warm edge spacers work together to keep the inner pane warmer, which helps limit condensation inside your home. This reduces the risk of mould, damp, and moisture-related damage while also improving everyday comfort, particularly in older properties.
Acoustic Insulation
Our glazing systems are designed to cut external noise by around 20 to 35 decibels, depending on the selected configuration. Laminated or asymmetric glass options can enhance sound reduction further, making them ideal for homes in busy areas. The result is a calmer, more peaceful living space.
Ventilation Integration
Our windows can be fitted with trickle vents where needed, with optional over frame vent hoods available for sash styles. Casement models also include secure night vent positions that allow fresh air in while maintaining safety. Ventilation sizes are carefully calculated to meet Document F requirements.
Unmatched Guarantees
All our double glazed windows come with comprehensive guarantees for lasting peace of mind. Each installation includes full product and workmanship coverage, ensuring your windows continue to perform at their best and keeping your investment protected for years to come.
Accreditations
Our windows are certified by over twelve recognised UK organisations for quality, safety, and performance. These accreditations show that every unit meets rigorous national standards, giving you confidence that your windows are manufactured and installed to the highest level.
Largest Double Glazing UK Suppliers
Colin’s Sash Windows is one of the UK’s leading suppliers of double glazed windows. Our size and experience let us provide consistent quality, dependable service, and competitive pricing. Homeowners enjoy the confidence of working with a company trusted on thousands of properties across the country.
Real Images Of Our
uPVC Windows In UK Homes
uPVC Windows Buying Guides
Areas We Deliver
We supply and install windows across most areas of the UK. Simply submit your postcode and project details to check available survey dates and lead times. Our uPVC window styles typically have some of the shortest lead times, around 2 to 3 weeks.
Delivery for our uPVC sash and casement windows is shown in the map below. Green areas have a delivery cost of £36, yellow areas cost £120+ (please contact our sales team for confirmation), and red areas are currently outside our delivery range.
Ready to Get Started?
If you’re considering new cheap uPVC windows or replacing existing ones, contact Colin’s Sash Windows today for a free, no-obligation quote and expert advice tailored to your property.
Get in Touch At Once!
Feel free to call us on 01525 552131. Our friendly sales advisors will guide you through the ordering process and help you with anything regarding double glazed windows. Alternatively, don’t hesitate to write us via the contact form or directly to our email address sales@colinssashwindows.co.uk. Don’t waste your time and take advantage of the finest quotes throughout the UK and Ireland.
