Window installation — A1 Window Construction Ltd
← All Services

Service

Windows

UPVC, aluminium, sash and bay — every type, made to measure, fitted to a standard that lasts decades.

Why Window Quality Matters

A badly fitted window draughts, leaks, and fails within years. A well-fitted window — with correctly prepared reveals, properly sealed frames, and quality glazing — performs for decades.

We measure every opening twice, order to exact dimensions, and fit with the attention to detail that prevents the issues other companies leave behind. That is why our customers keep coming back.

Made-to-measure — every frame ordered to your exact dimensions

Correct reveal preparation before every fit

Full foam and silicone seal on every window

Clean finish inside and out, dust sheeting used throughout

Written quotation before any work begins

Premium anthracite aluminium casement window with white reveals and golden garden light — A1 Window Construction Ltd

Window Types

We Supply & Fit Every Type

UPVC casement windows installed Cheam Sutton Surrey — A1 Window Construction Ltd

UPVC Casement Windows

The most popular choice for UK homes. We install using the Kömmerling 70 UPVC system — five-chambered profiles regarded as the pinnacle of the industry for thermal performance, design engineering and energy efficiency. Low-maintenance and available in 22 standard colours plus woodgrain foils.

Kömmerling 70 system — five-chambered UPVC profiles

U-value as low as 0.85 W/m²K with triple glazing

22 standard colours + woodgrain foils

A-rated energy efficiency as standard

Multi-point locking as standard

10-year manufacturer guarantee

Get a Quote
Slim-frame aluminium windows installed on extension Cheam Surrey — A1 Window Construction Ltd

Aluminium Windows

Slim sightlines, architectural precision, and exceptional strength. We supply the ALUNA aluminium casement system by Alunet — super-slim sash profiles, Energy Rated A, and PAS24:2022 certified. The choice for contemporary extensions, new builds, and any project where aesthetics matter.

ALUNA aluminium system by Alunet — super-slim sash

Energy Rated A (WER) — exceeds Part L requirements

U-value 1.4 W/m²K — thermally broken as standard

PAS24:2022 security certified

Any RAL colour — powder-coated, 10-year finish guarantee

Suitable for large format openings

Get a Quote
Sliding sash windows Victorian Edwardian property Sutton Surrey — A1 Window Construction Ltd

Sliding Sash Windows

Period-correct sash windows for Victorian and Edwardian properties. Authentic vertical slide, run-through horns, and the look of traditional timber — with modern UPVC performance.

Authentic Georgian proportions

Spiral balance mechanism

Run-through horns for period accuracy

Tilt-in for easy cleaning

Available in White and Woodgrain

Get a Quote
Anthracite aluminium bay windows fitted Surrey — A1 Window Construction Ltd

Bay & Bow Windows

Bay and bow windows add space, light and character to any room. We design and fit bespoke bay configurations to match your existing property perfectly.

Square, angled and curved bays

Flush or traditional external cill

UPVC or aluminium frames

Matching internal and external cill boards

Structural survey included

Get a Quote

FAQs

Window Questions Answered

How long does a window installation take?

Most window replacements are completed in a single day. A full house (8–12 windows) typically takes one to two days. We work efficiently and leave the site clean and tidy at the end of each day.

Are your windows energy-efficient?

Yes. All our windows are A-rated for energy efficiency as standard, with optional upgrade to triple glazing for maximum thermal performance.

Do you take the old windows away?

Yes — we remove and dispose of all old windows as part of the installation. There are no hidden disposal charges.

Can I choose any colour?

UPVC windows come in a wide range of standard colours and woodgrain foils. Aluminium windows can be powder-coated in any RAL colour you choose.

Do you offer a guarantee?

Yes. All our window installations come with a minimum 10-year manufacturer guarantee on the frames and sealed glazing units.

Ready for New Windows?

Free, written quote. No obligation. Will or Sam will visit your property and assess every opening before anything is ordered.