Aluminium Casement Windows
Slimline and high-performance aluminium casement windows with clean sightlines and strong thermal and acoustic options.
We confirm the appropriate product route per project at quote, based on the opening, drawings, performance target, glass and finish.
Lead time confirmed at quote, never a guess. Pricing per project, never a stock figure.
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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. Premium routes in the same family reach better thermal and acoustic figures than the ones below, and are quoted where the project calls for them. Either way this is the envelope, not a quotation: the achievable figures for your opening are confirmed against your drawings and a survey.
| Frame sightline | 58mm |
|---|---|
| Panels per run | 1 to 4 |
| Leaf width | 350 to 1370mm |
| Height | 400 to 2400mm |
| Maximum leaf weight | 180kg |
| Glazing unit | 24 to 40mm |
| Glazing options | Double |
| U-value from, this system | 1.2 W/m²KThermal transmittance, triple glazing with Ug 0.7 |
| Security | PAS24 |
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.
| Tested size | Air permeability | Watertightness | Wind resistance |
|---|---|---|---|
| 2100 x 2100mm | Class 3 (450 Pa) | Class 7A (300 Pa) | CE2400 (2400 Pa) |
| 1200 x 1500mm | Class 4 (600 Pa) | Class E1050 (1050 Pa) | CE2400 (2400 Pa) |
| 2000 x 1400mm | Class 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 holds no certification of its own. Evidence for the configuration you specify is issued at quote.
In place
Aluminium Casement Windows we have made
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.
For homes
Love these for your home?
VitrineAlu supplies through the trade. Send a referral request and we will review the product route before any installer handoff, and your details are only passed on with your consent. Your installation contract and warranty remain with the installer you choose to proceed with.
Specification
Aluminium Casement Windows
- Sightline
- 58 mm
- Glazing
- 24-40 mm
- Leaves
- up to 4
- Security
- PAS 24 route
- Status
- Capability, confirmed at quote
- Thermal
- Whole-window U-values from 0.85 W/m²K where specified
- Size and Weight
- Sashes up to 1.3 m × 2.4 m at up to 160 kg where specified
- Security
- PAS 24 tested-security routes
- Glazing
- Double, triple and acoustic units up to 55 mm, project-specified
- Finishes
- Full RAL, dual-colour and anodised-style finishes
- Configurations
- Flush or standard sash, French casement, fixed lights and combinations
- Weather
- Air permeability Class 4, watertightness to Class E1800, wind resistance to Class C5; acoustic up to Rw 46 dB
Figures are achievable capability for the system, not a quotation. The route, glass and hardware that deliver them are confirmed per project.
Request current test evidenceFaster quote
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.
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 routes and energy efficiency and U-values.
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 1.3 m by 2.4 m at up to 160 kg where specified, 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 up to 55 mm, project-specified, with toughened or laminated panes, warm-edge spacers and low-emissivity coatings. Glazing sets the outcome, so whole-window U-values run from 0.85 W/m²K and acoustic to Rw 46 dB where specified. Confirm the whole-unit Uw at quote. 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 tested-security routes where the project requires it, with laminated glazing for added resistance. Watertightness reaches Class E1800 and wind resistance Class C5 where specified, 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 up to 55 mm, so the choice is aesthetic. We quote either. Browse the casement range to compare, and confirm the glazing thickness for your opening at quote.
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