Hardware groove
Most export systems use the Euro groove (often called C-groove) so standard European espagnolettes, hinges and tilt-turn gear fit. Some markets use their own groove geometry; match it to the hardware your installers already stock.
Project and OEM profile supply
Aluminium Casement Windows for Projects and OEM Buyers
Buying aluminium casement windows for a project or a distribution programme is mostly about matching one opening type to many different requirements: the local market's opening direction, its test standards, the energy target, the hardware groove your installers know, and how units are labelled and packed. This page sets out those choices for contractors, developers, importers and window fabricators. Metline supplies casement profiles, cut-to-size sections and accessories in 6063 and 6060 aluminium to window fabricators worldwide.
- Profile alloy
- 6063-T5 / T6, 6060-T66
- Supply forms
- Profile lengths, cut-to-size profiles, accessories
- Openings
- Outward, inward, tilt-turn, flush
- Standards
- EN 14351-1 · NAFS · AS 2047
Why projects specify casement windows
When a casement is closed, its locking points draw the sash tight onto continuous gaskets. Nothing has to slide past a seal, so air, rain and sound have no easy path through. That single feature explains why casements consistently test better than sliding windows for air permeability, watertightness and acoustic reduction, and why energy and acoustic specifications so often name them.
Casements are also flexible. The same profile family can produce outward and inward sashes, tilt-turns, fixed lights and combinations, so one system can cover most of a building's openings with matching sightlines and colour. For a distributor or window company, that means fewer profile codes in stock and simpler fabrication.
The trade-off is that an open casement projects from the wall. Outward sashes need clearance from walkways and balconies and restrictors at height; inward sashes need clear space for curtains and furniture. Where neither is possible, a sliding window remains the practical choice.
Casement product lines and who they suit
| Line | Typical buyer | Focus | Usual configuration |
|---|---|---|---|
| Standard casement | Distributors, housing developers, warm-climate projects | Cost, speed of supply, basic ventilation | Non-insulated or entry thermal break, 5-12-5 double glazing, polyester powder coat |
| Thermal break casement | UK, European, Australian and cold or hot-climate projects | U-value, air tightness, condensation control | 60 – 80 mm system, Low-E argon glazing, multi-point locks |
| Flush casement | Refurbishment contractors, villas, boutique hotels | Sash flush with frame, traditional look | Slim face widths, concealed drainage, dark or heritage colours |
| Slim-frame casement | Architect-led homes and commercial interiors | Maximum glass, minimum frame | Deeper, thicker-walled sections to keep strength with narrow faces |
| Tilt-turn | Apartment, school and hotel developers | Safe ventilation and inside cleaning | Inward-opening, 70 mm+ system, tilt-turn gear and restrictors |
| Fixed + casement combinations | Offices, schools, apartment facades | Daylight with a controlled opening ratio | Large fixed lights with one or two opening sashes, reinforced mullions |
For the engineering behind each type (how gaskets, drainage, multi-point locks and corner joints produce the performance), see our casement window systems page.
What different markets expect from a casement
| Market | Typical opening habit | Key documents and rules |
|---|---|---|
| United Kingdom and Ireland | Outward and flush casements; tilt-turn on apartments | EN 14351-1 (UKCA/CE), Approved Document L energy limits, PAS 24 security, Part Q for new homes, fire escape and restrictor rules |
| Continental Europe | Inward-opening and tilt-turn | CE marking to EN 14351-1 with air, water, wind and Uw declared; national energy rules |
| North America | Outward casements with crank or push-out operators | NAFS performance class and grade, NFRC U-factor and SHGC labels, local energy codes |
| Australia and New Zealand | Outward casements and awnings | AS 2047 wind and water ratings by site class, AS 1288 glass, NCC energy and WERS; NZS 4211 and H1 in New Zealand |
| Middle East | Outward and tilt-turn; many fixed lights | Wind and sand exposure, high solar gain, local green building codes, coastal finishes |
| South and Southeast Asia | Outward casements, often with insect mesh | Monsoon watertightness, typhoon wind loads in some regions, dust and humidity resistance |
Always confirm the authority's and consultant's document list before production. Test reports apply to the tested size, glass and hardware, so they must cover the largest sash on the schedule.
Choosing a system depth by budget and target
| Tier | Frame depth | Thermal break strip | Typical glazing | Buyer priority |
|---|---|---|---|---|
| Standard thermal break | about 50 – 65 mm | about 15 – 28 mm | 5-12-5 or 6-12-6 double | Controlled cost and fast turnaround |
| High insulation | about 70 – 80 mm | about 30 – 40 mm | Low-E argon double; slim triple optional | U-value target and condensation control |
| High performance | about 80 – 95 mm | wide strips with foam | Triple or acoustic laminated IGU | Wind, water, acoustics on high-rise and coastal sites |
| Passive-house direction | 90 – 100 mm+ | very wide strips and inserts | Triple Low-E with warm-edge spacers | Very low U-value, continuous air tightness |
| Slim / flush | about 70 – 90 mm | by system | Double or triple | Appearance with structural adequacy (walls about 1.8 – 2.0 mm) |
Ranges are typical of the market; actual limits come from the selected system's test report. Profiles are normally extruded in 6063-T5 or T6, or 6060-T66 in Europe; our 6063 aluminium guide lists the alloy data.
Hardware, glass, gasket and finish options
Hinges and stays
Butt hinges, friction stays or concealed hinges. Confirm the rated sash weight: a 1.0 × 1.6 m sash with 6-16-6 glass already weighs around 55 – 60 kg.
Locking
Multi-point espagnolettes for sashes over about 1 m high or in exposed sites; keyed handles and secured-by-design hardware where security rules apply.
Restrictors
Opening limiters and child-safety catches for upper floors, schools, care homes and hotels.
Glass
Double or triple IGUs, Low-E and solar-control coatings, laminated and acoustic laminated glass, toughened safety glass at low level.
Gaskets
EPDM single, double or triple sealing; moulded corners reduce leakage risk; brush seals only at screens.
Insect screens
Fixed, hinged or retractable screens, mounted inside for outward sashes and outside for inward ones.
Finish
Polyester or super-durable powder, PVDF, anodising, wood-grain transfer and dual colour on thermally broken profiles.
Brand matching
Project hardware brands or equivalents can be matched to a specification on request, subject to the system test.
Fabrication checks that decide long-term performance
Two casements built from the same system can perform very differently depending on fabrication. These are the checks your fabricator should apply, and the ones a buyer should ask any window maker about.
| Check | What is controlled | Why it matters |
|---|---|---|
| Cutting | Profile length and mitre angle to the cutting list | Open mitres break the gasket line and let water into corners |
| Corner joints | Cleat crimping force, structural adhesive, corner sealant | Decides squareness and whether the frame stays sealed for decades |
| Squareness | Diagonal difference of frame and sash, typically within a couple of millimetres | Out-of-square sashes compress gaskets unevenly and leak |
| Drainage | Position, size and cover of drainage slots | Blocked or misplaced slots cause leaks at the sill |
| Gaskets | Continuity, corner joints, correct profile for the system | Gaps at corners are the most common air-leakage path |
| Glazing | Setting blocks, toe-and-heel packing, bead fit | Prevents sash drop and keeps the sash operating smoothly |
| Hardware | Fixing positions, locking-point engagement, operating force | Even compression and easy operation for users |
| Finish | Film thickness, colour and gloss against the approved sample | Batch consistency across a whole facade |
Profile shipments carry mill test certificates for the alloy, and cut and machined profiles are checked for length, mitre and finish before packing. Metline is ISO 9001 certified, and third-party inspection can be arranged.
Project, OEM and distributor supply models
Project profile supply
Profiles for a whole project, finished in one colour batch and labelled by floor, elevation and schedule reference for the fabricator.
Cut-and-machined profiles
Profiles cut and machined to the schedule, with gaskets, cleats and hardware in labelled bundles, for fabricators who assemble and glaze locally to save freight and import duty.
Profile lengths
Stock-length profiles in mill finish, anodised or coated, for window companies running their own production.
OEM programmes
Private labels, bundle or crate marking and barcodes for profiles and accessories, in the buyer's format for distributors and importers.
- Schedule reviewWe check the window schedule or drawings against the system's tested sizes and the market's rules.
- ConfigurationSystem depth, profile series, hardware, gaskets, screens and finish agreed, with section drawings and colour samples.
- ProductionProfiles extruded and finished, then cut and machined where the supply model requires.
- Inspection and packingProfiles and accessories checked, labelled and protected with film, edge guards and export packing.
- ShippingDelivered on EXW, FOB, CIF or DAP terms with packing lists and certificates.
References and standards
- EN 14351-1 – Windows and doors: product standard, performance characteristics
- AAMA/WDMA/CSA 101/I.S.2/A440 – North American Fenestration Standard
- AS 2047 – Windows and external glazed doors in buildings
- EN 12207, EN 12208 and EN 12210 – Air permeability, watertightness and wind resistance classification
- EN 755-2 – Extruded rod, bar, tube and profiles: mechanical properties
Aluminium (aluminum) casement windows for projects: frequently asked questions
Should a project choose casement or sliding windows?
Choose casements where air tightness, watertightness, acoustics or a low U-value are specified, because the sash closes onto compressed gaskets. Choose sliders for very wide openings, where a projecting sash would obstruct a balcony or walkway, or where budget outweighs performance.
What sets the final U-value of an aluminium casement?
Mainly the glass unit, then the thermal break width and shape, the frame face width and the spacer bar. Compare whole-window values calculated at the same reference size to EN ISO 10077 or NFRC 100.
Are aluminium casements suitable for coastal, humid or high-wind sites?
Yes, with a system tested to the required wind and water class, adequate mullion sections, a marine-grade finish such as super-durable powder, PVDF or thick anodising, and stainless or coated hardware.
Which projects suit tilt-turn casements?
Apartments, schools, hotels and high-rise housing, where secure tilt ventilation and cleaning from inside are valuable, and in markets such as continental Europe where inward opening is standard.
Do you supply finished casement windows?
No. We supply cut-and-machined profiles with gaskets, cleats and hardware for fabricators who assemble and glaze locally, as well as stock profile lengths for window companies.
Do you support OEM labelling and packing?
Yes. Profile bundles and accessory cartons can carry the buyer's labels, barcodes, schedule references and part numbers, packed in crates or cartons to the agreed format.
What do you need for a quotation?
Project location or target market, window schedule or drawings, opening types, performance targets, glass, hardware, finish, supply model (profile lengths or cut-and-machined profiles), quantity and delivery destination.
Sourcing casement window profiles for a programme?
Send the schedule, target market, glass, hardware and finish. Our team will propose a profile series and quote profiles and accessories.
