uPVC Windows — London & the Home Counties
Overview
Warm, secure and virtually maintenance-free — our uPVC windows combine A+ rated thermal performance with a finish that keeps its edge for decades. Fabricated in Britain from Deceuninck and Rehau 70mm profiles, available in every standard, heritage and foil-wrapped colour, with a full choice of hardware and glass.
Deceuninck / Rehau six-chamber 70mm uPVC profile · A-rated double or triple glazing · Warm-edge Super Spacer · Stainless steel Yale locking gear · Q-Lon compression seals
0.9–1.4 W/m²K Window U-values
Six-chamber profiles, warm-edge spacer bars and argon-filled units deliver energy-efficient whole-window performance for London and Home Counties properties.
PAS 24 Secured Locking
Yale multi-point espagnolette locking, internal beading, laminated inner panes and shootbolts as standard. Independently tested to PAS 24:2016 and compliant with Approved Document Q.
Acoustic Glass Options
Upgrade to 6.4mm acoustic laminate for up to 37 dB reduction — ideal for arterial roads, flight paths and terraced streets in Zones 1–4.
Colour & Foil Choice
White, Anthracite Grey, Chartwell Green, Painswick, Agate Grey, Cream, oak- and rosewood-effect foils, plus sprayed RAL to order. Dual-colour (different inside/out) across the range.
10-Year Guarantee, 10-Year Colour-Fast Foils
Every installation carries an insurance-backed 10-year guarantee. Our foil finishes carry a 10-year colour-fastness warranty — they will not crack, flake or fade like painted timber.
Clean-Site Installation
CERTASS-registered fitters, dust sheets on every floor, old frames removed and recycled, plaster made good, cills silicone-sealed. Most homes are re-glazed in 1–2 days.
uPVC vs Aluminium vs Flush Casement
Compare whole-window U-values, energy ratings and frame performance for uPVC, aluminium and flush casement windows installed across London and the Home Counties.
uPVC
- Best for
- Every home — modern & period
- Frame sightlines
- Standard (~70mm)
- Maximum pane size
- Up to ~1.8m tall
- U-value (as low as)
- 0.9 – 1.4 W/m²K
- A+ energy rating
- Yes
- PAS 24 security
- Yes
- Colour choice
- 20+ foil finishes
- Dual inside / outside colour
- No
- Conservation-area friendly
- Case-by-case
- Mechanical (not welded) joints
- No
- Maintenance
- Wipe-clean, none
- Guarantee
- 10-year insurance-backed
Aluminium
- Best for
- Contemporary builds, large apertures
- Frame sightlines
- Slim (~55mm)
- Maximum pane size
- Up to ~3m tall
- U-value (as low as)
- 0.9 – 1.4 W/m²K
- A+ energy rating
- Yes
- PAS 24 security
- Yes
- Colour choice
- Any RAL, dual colour
- Dual inside / outside colour
- Yes
- Conservation-area friendly
- No
- Mechanical (not welded) joints
- Yes
- Maintenance
- Wipe-clean, none
- Guarantee
- 20-year finish + structural
Flush Casement
- Best for
- Period, cottage & listed homes
- Frame sightlines
- Slim, timber-look
- Maximum pane size
- Up to ~1.8m tall
- U-value (as low as)
- 0.9 – 1.4 W/m²K
- A+ energy rating
- Yes
- PAS 24 security
- Yes
- Colour choice
- Heritage foil palette
- Dual inside / outside colour
- No
- Conservation-area friendly
- Yes
- Mechanical (not welded) joints
- Yes
- Maintenance
- Wipe-clean, none
- Guarantee
- 10-year colour-fastness
Not sure which range fits your property? Book a free survey and we'll bring samples of all three to your door — no obligation, just honest advice.
uPVC vs aluminium vs flush casement — the answers we're asked most.
- Which energy-efficient windows are best for London and Home Counties homes?
- Our uPVC, aluminium and flush casement ranges achieve a whole-window U-value of 0.9 – 1.4 W/m²K. uPVC has naturally low frame conductivity, thermally broken aluminium combines slim sightlines with the same approved range, and heritage flush casements suit period and conservation homes across London and the target counties.
- When should I choose aluminium windows over uPVC?
- uPVC is a strong all-round choice for standard-sized apertures. Aluminium comes into its own on large panes above roughly 1.8m, contemporary builds where slim sightlines matter, and projects needing a bespoke RAL or dual inside/outside colour. For modest openings focused on thermal performance, uPVC is usually the natural fit.
- Will flush casement windows suit a conservation area or listed building?
- Yes — flush casements are our go-to for conservation areas, AONBs and listed properties. The sash sits flush with the frame (mimicking traditional timber joinery), corners are mechanically jointed rather than welded, and heritage foil finishes replicate painted timber convincingly. We regularly get them approved where standard uPVC would be refused.
- Can I mix window types on the same house?
- Absolutely — and we often recommend it. A common combination is flush casements to the front elevation for kerb appeal and standard uPVC or aluminium to the rear where a contemporary look and larger glazed openings take priority. Colours can be matched across ranges so the house reads consistently from every angle.
- How long do each type of window last?
- Modern uPVC frames are engineered for 35+ years of service and come with a 10-year insurance-backed guarantee. Aluminium frames outlast the building in most cases and carry a 20-year finish guarantee. Flush casements share uPVC's core structure with heritage foils that carry a 10-year colour-fastness warranty. All three use the same locking systems and Q-Lon seals.
- Which range offers the widest colour choice?
- Aluminium is the clear winner — any RAL colour, matt or satin, plus different colours inside and out. uPVC comes in 20+ foil finishes including anthracite grey, Chartwell green, cream and popular woodgrains. Flush casements share the heritage end of the uPVC palette (painted-timber creams, sage, off-black) and are limited to a single colour throughout.
- Are all three ranges equally secure?
- Yes — every window we install is PAS 24 tested and fitted with multi-point locking, laminated glass options and Secured by Design compatible hardware. The frame material doesn't change the security rating; the locking system, glass specification and installation quality do.
- How do I choose between the three ranges for my home?
- Start with the property's character. Period cottage or listed home in a conservation area → flush casement. Contemporary new-build or large glazed opening where sightlines matter → aluminium. Everything else, where value and long-term thermal performance are the priority → uPVC. Book a survey and we'll bring samples of all three so you can compare them at the house.
The homeowner's guide to uPVC vs Aluminium vs Flush Casement.
An 8-page PDF you can read in ten minutes. Side-by-side specs, clear performance comparisons, range-by-range detail and the six questions we're asked most. No email required — download and share freely.
- Full specification table — U-values, sightlines, guarantees, design suitability
- Which range suits period, contemporary and conservation-area homes
- Six FAQs and a checklist for booking your survey
Instant download · No email required · Share it with your architect, builder or partner.
Engineered to the millimetre.
Every frame we install is made to your survey sizes with the following performance envelope as standard.
- U-value (whole window)
- 0.9 – 1.4 W/m²K
- Window Energy Rating
- A+ (up to A++ triple-glazed)
- Acoustic reduction
- Up to 37 dB Rw with laminate upgrade
- Security
- PAS 24:2016 · Secured by Design · Doc Q compliant
- Profile depth
- 70 mm, six-chamber
- Glass options
- 4/20/4 argon low-e · triple-glazed · self-cleaning · obscure · laminate
- Colours
- 12 stocked foils + full RAL sprayed to order
- Guarantee
- 10-year insurance-backed · 10-year colour warranty
The upvc windows family.
Every one of the following styles is available in the upvc windows range — mix, match and specify at survey.
A calm, predictable process.
No sales calls, no pressure, no surprises. Every project follows the same six steps — with a named surveyor from start to finish.
- 01Day 0
Enquire
Send photos and rough sizes — we come back within one working day with initial guidance.
- 02Week 1
Home survey
A senior surveyor visits, measures, advises on Doc L and Doc Q compliance and confirms a fixed quotation.
- 03Week 1–2
Design & sign-off
Drawings, colour swatches, hardware and glass samples brought to your home. Deposit taken only when you're happy.
- 04Weeks 2–7
Manufacture
Made to your survey sizes in our British fabrication partner's factory — typical lead time 3–5 weeks.
- 05Fit week
Installation
Two-person CERTASS-registered fit team, dust-sheeted throughout. Most whole-house jobs complete in 2–4 days.
- 06Ongoing
Aftercare
CERTASS certificate lodged, insurance-backed guarantee registered, 12-month courtesy inspection and lifetime servicing on request.
When upvc windows isn't the right answer.
We'd rather lose a job than sell the wrong window. Here's when to consider the alternatives.
uPVC Windows across London
and the Home Counties.
We install upvc windows across six counties — every project surveyed, made and fitted by our in-house team. Choose your county to read local knowledge, planning notes and recent work.
See all areas covereduPVC Windows — installed.
A selection of recent installations across London and the Home Counties, photographed on site.
Practical answers.
Everything homeowners ask us about upvc windows — survey, lead times, guarantees and coverage.
How long do uPVC windows last?+
A well-installed uPVC window from our range is engineered for a service life of 25–35 years. All frames carry a 10-year insurance-backed guarantee and 10-year colour warranty on foil finishes.
Can I match my existing windows?+
Yes. We survey existing frames and match sightlines, colour and glazing bar detail so replacements sit correctly in period and modern properties alike. Astragal, Georgian and lead-effect bars are all available.
Do you replace one window at a time?+
Absolutely. Whether it's a single unit or a full house, our installers work cleanly and finish to the same showroom standard. Minimum order value applies.
What affects the specification for uPVC windows?+
Window size, opening configuration, colour, glass and hardware all shape the final specification. We confirm every detail after a measured home survey.
Are trickle vents required?+
Since June 2022, Approved Document F requires background ventilation on nearly all replacement windows in England. We fit slot-style trickle vents colour-matched to the frame — barely visible from below.
Do uPVC windows work in a conservation area?+
Sometimes. Officers generally prefer flush casements or timber; standard uPVC casements are usually accepted outside designated conservation zones. We prepare drawings and finish samples for your planning officer at no charge.
What's the difference between A, A+ and A++ rated?+
The Window Energy Rating (WER) balances heat loss and solar gain. A is the pass mark, A+ is our standard double-glazed spec, A++ is triple-glazed. Upgrading from older C-rated units to A+ glazing can noticeably reduce heat loss.
What U-value do your uPVC windows achieve?+
Our uPVC windows achieve whole-window U-values of 0.9–1.4 W/m²K. We confirm the exact figure for each measured opening across London, Buckinghamshire, Hertfordshire, Bedfordshire, Northamptonshire and Oxfordshire.
Can I have a different colour inside and outside?+
Yes — dual-colour foil is available across the range. White inside with Anthracite Grey outside is our most-requested combination.
What happens to my old windows?+
Frames and glass are separated on site, glass recycled locally and uPVC profiles taken to a licensed recycler — nothing goes to landfill. CERTASS lodges the compliance certificate within 10 working days.
Enquire about
uPVC Windows.
Speak with our design team, book a home survey, and receive a fixed written quotation — all with no obligation.
Call · 020 3633 0405