Aluminium Casement Windows

Slimline and high-performance aluminium casement windows with clean sightlines and strong thermal and acoustic options.

Send the opening and we tell you the day your price will be ready. We confirm the appropriate product route per project at quote, based on the opening, drawings, performance target, glass and finish.

Lead time and price are worked out for your job at quote.

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Run of casements across a brick facade

Fabricated in Haydock, St HelensTrade-only supply from our own workshop.

Trade-firstInstallers, builders, architects, specifiers, joiners and commercial teams.

Quote-confirmed specificationProduct route, performance targets, glass and finish are confirmed per project.

Fabrication record

What aluminium casement windows can actually be built to

These are the limits the factory works to, taken from the fabrication data for the system we make this product in. This is the envelope, not a quotation: the achievable figures for your opening are confirmed against your drawings and a survey.

Fabrication limits for Aluminium Casement Windows
Frame system58mm
Lights per frame1 to 4
Leaf widthto 1370mm
Heightto 2400mm
Maximum leaf weight180kg, heavy-duty hinges
Glazing unit24 to 40mm
Glazing optionsDouble, Triple
U-valueUw 1.4 W/m²K double-glazed (Ug 1.0), 1.2 triple-glazed (Ug 0.7), at the 1357.5 x 1480 mm test size. Confirmed at quote for your opening.Read from the U-value table for the system we make this product in
SecurityPAS 24 routes where specified

Configurations available

  • Fixed light, side light, fan light, top hung, side hung, French casement, cruciform, coupled window, corner post, bay pole, window-over-fixed

Tested performance

Three separate mock-ups were tested and they do not agree, so all three are shown. A class belongs to the size it was achieved at.

Classified test performance for Aluminium Casement Windows
Tested sizeAir permeabilityWatertightnessWind resistance
2100 x 2100mmClass 3 (450 Pa)Class 7A (300 Pa)CE2400 (2400 Pa)
1200 x 1500mmClass 4 (600 Pa)Class E1050 (1050 Pa)CE2400 (2400 Pa)
2000 x 1400mmClass 3 (450 Pa)Class E1200 (1200 Pa)CE2400 (2400 Pa)

Each row is a separate tested mock-up. A class is achieved at a size, so these are not a guarantee for every configuration. The classes that apply to your opening are confirmed at quote.

Any security rating above is the tested performance of the system, held by the system manufacturer. VitrineAlu fabricates to the tested configuration and the test evidence belongs to the system it was tested on. Evidence for the configuration you specify is sent at quote.

Design tool

See your aluminium casement windows to scale

Use the concept visualiser to explore approximate size, opening, glazing, finish and detailing before a quote request. It is a discussion aid, not a production drawing or evidence of technical suitability; current project review confirms the selected aluminium casement windows route.

Trade accounts only. Apply for one, or send drawings for an estimate instead.

Open the designer

For homes

Love these for your home?

VitrineAlu supplies through the trade. Send a referral request and we will review the product route before it is passed to your installer, and your details are only passed on with your consent. Your installation contract and warranty remain with the installer you choose to proceed with.

Request local installer referral

Specification

Aluminium Casement Windows

Frame system
58 mm
Glazing
24 to 40 mm
Security
PAS 24 routes where specified
Status
Capability, confirmed at quote

The figures for this product are in the fabrication record above. The route, glass and hardware that deliver them are confirmed per project.

Request current test evidence

Priced first time

What to send

Send these and the route can be confirmed without a back-and-forth.

  • Window style: side-hung, top-hung, fixed light, multi-light, flush or hidden-vent look.
  • Thermal, acoustic, ventilation, restrictor and safety-glass requirements.
  • Colour, glazing and project exposure so the final specification can be assessed.
Send details

How we specify

The right product route is chosen per project

Exact specification (U-value, sizes, weights, security class, finish) is confirmed per project at quote, selected to suit the trade brief.

It means you lead with the outcome: light, security, clean sightlines, usable openings, buildable details and a specification that suits the drawings.

More on how routes are specified: security and PAS 24, and energy efficiency and U-values.

Best fit

  • Trade installers
  • Builders
  • Architects & specifiers
Get the opening priced

Common questions

How slim are the sightlines on aluminium casement windows?

Aluminium carries glass on slim frames, so casements hold tight sightlines and push more daylight across the elevation. Sashes run up to 1.37 m by 2.4 m at up to 180 kg on heavy-duty hinges, on the system we fabricate, in flush or standard sash, French casement, fixed lights and combinations. We confirm face widths against your openings at quote.

Do aluminium casement windows need trickle vents under Part F?

Usually yes. Part F expects background ventilation, so most replacement casements ship with trickle vents unless the installer confirms an alternative. Vents sit in the frame, so airflow is met without spoiling sightlines, and air permeability is tested to Class 4 where specified. Your installer signs off on site. Start a trade quote with your schedule.

What glazing make-up goes into aluminium casement windows?

Double, triple and acoustic units from 24 to 40 mm, project-specified, with toughened or laminated panes, warm-edge spacers and low-emissivity coatings. Glazing sets the outcome. From the system's U-value table: Uw 1.4 W/m²K double-glazed (Ug 1.0), 1.2 triple-glazed (Ug 0.7), at the 1357.5 x 1480 mm test size. Confirmed at quote for your opening. Acoustic performance for your glass is confirmed at quote; Rw 46 dB is available on the premium route, where specified. See energy efficiency for the thermal side.

What are the security routes for aluminium casement windows?

Aluminium casements take multi-point locking and PAS 24 routes where the project requires it, with laminated glazing for added resistance. Tested mock-ups on record reach watertightness Class E1200 and wind resistance CE2400, each at its tested size, so the closed unit performs. We support the test routes and the documentation trail. See security, then raise a quote.

Flush or standard sash on aluminium casement windows, which should I pick?

A flush sash sits level with the outer frame for a flat, contemporary face that suits modern and heritage-sensitive work. A standard sash steps proud for a traditional look. Both share the same hardware and glazing, including acoustic units within the 24 to 40 mm the system takes, so the choice is aesthetic. We quote either. Browse the casement range to compare, and confirm the glazing thickness for your opening at quote.

Verified business details

VITRINEALU LTD

Fabrication works
Unit 1 Nassau Business Park, Bahama Road, Haydock, St Helens, WA11 9FW

Work with us

Send the drawings. We specify it, fabricate it and hand it over.

Trade Workshop & Estimating

Ask Workshop Desk

Trade fenestration advice & specs. For live orders or schedules, contact Paul & the workshop desk.

Quote checklist & factory finishes

Quote Requirements:

  • Structural opening (width × height mm)
  • Sash configuration & opening direction
  • Glazing spec & cill / threshold
  • Factory powder-coat finish

Standard Factory Finishes:

Dual colour & special RAL available on request.

2026 UK Building Regulations:

Paul Fradley | Trade Workshop Desk

Morning / Afternoon, I’m Paul from VitrineAlu’s fabrication shop in Haydock. Ask me anything on profiles, sightlines, Document L compliance or opening sizing for your quote enquiry.

    Chat history is available for up to an hour.