Aluminium window manufacturers turn lengths of aluminium profile into finished windows and doors: they cut the profiles to size, machine them for drainage and hardware, join the corners, glaze the frames and fit the handles, stays and rollers. In Gauteng there are many of them, from small workshops to large factories, and the quality, glass, prices and lead times vary a lot. This guide explains how aluminium windows are made and gives you nine checks to choose between aluminium window manufacturers in Gauteng with confidence.
Coetz™ is one of them. We make aluminium windows and doors to order at Laser Park, Johannesburg, and supply them across Gauteng and nationwide – so every check below is one we hold ourselves to.
Contents
How aluminium windows are made
- Extrusion. Aluminium billet is pushed through a die to make long profiles – frames, sashes, mullions and beads. Most aluminium window manufacturers buy these profiles from an extruder rather than making them.
- Finishing. The profiles are powder-coated (White, Bronze, Charcoal, Black) or anodised (Natural Anodised), which protects the aluminium and gives the colour.
- Cutting and machining. Each profile is cut to the exact size of your window and machined for drainage slots, hinges, stays, locks and rollers.
- Assembly. The corners are joined, the sashes are built and the hardware is fitted.
- Glazing. The glass is set into the frame with gaskets or glazing beads. At Coetz™ that is always 6.38 mm clear laminated safety glass.
- Checking. The finished unit is checked for size, square and smooth operation before it is wrapped for delivery.
Manufacturer, supplier or installer?
These three roles are often confused, and knowing which one you are dealing with avoids surprises.
| Role | What they do | Coetz™ |
|---|---|---|
| Manufacturer | Makes windows and doors from aluminium profile and glass | Yes – made to order at Laser Park |
| Supplier | Sells and delivers finished units | Yes – Gauteng and nationwide |
| Installer | Fits the units into your building | No – supply only for windows and doors |
MC Automations, our parent company, installs aluminium shopfronts and automatic doors. For aluminium windows and doors, your builder or installer does the fitting – see how to install aluminium windows and aluminium window installers.
Nine checks when choosing aluminium window manufacturers in Gauteng
1. Safety glass as standard
Glass in doors, beside doors and in low-level panels must be safety glass under SANS 10400-N. Ask whether laminated safety glass is standard or an extra. Every Coetz™ window and door comes with 6.38 mm clear laminated safety glass as standard.
2. Published prices
Good aluminium window manufacturers can tell you the price before you commit. Coetz™ shows every price online, excluding VAT, and the online estimator prices a whole house in one list – for example, a 600 × 600 mm fixed window is R822 and a 1 200 × 1 200 mm single-opener top hung window R3 475 in White (prices as at 19 October 2026).
3. A clear lead time
Ask aluminium window manufacturers how long manufacturing takes after you order. Coetz™ makes units to order in 1–2 days.
4. Your sizes, with a fitting gap
Check the size range and how the manufacturer handles the fitting gap. Coetz™ makes every unit 10 mm smaller than the catalogue size in each direction, so it fits into the opening with room for packers and sealant. See aluminium window sizes.
5. Colours and what they cost
Ask which finishes are standard and which cost extra. Coetz™ offers White, Bronze and Charcoal at the same price, Black at about 10% more and Natural Anodised at about 20% more.
6. A drawing to check before you pay
A drawing shows you which panels open and which side the hinges are on. Every Coetz™ product drawing is shown as viewed from inside the room, so you can check it against your opening.
7. A written warranty
Ask aluminium window manufacturers for the warranty in writing and check what it covers. Coetz™ covers aluminium frames, glass and powder-coated finishes for 5 years, and hardware and seals for 2 years, against manufacturing defects – see our warranty.
8. Delivery across Gauteng
Check the delivery cost before you order. Coetz™ charges delivery once per order: R650 in Johannesburg and R950 in the rest of Gauteng (R1 850 nationally, and more for any unit longer than 2.4 m), or you can collect free from Laser Park. See delivery.
9. A registered company you can visit
Choose aluminium window manufacturers with a registered company and a physical address you can visit. Coetz™ is part of MC Automations (Pty) Ltd, a member of the South African Glass and Glazing Association, SAGGA (Reg. No. S7813).
Aluminium door manufacturers: the same checks apply
Aluminium door manufacturers in Gauteng make sliding, stacking, folding, hinged, French and stable doors in the same way, and the nine checks above apply equally. For doors, also ask about the threshold height and the panel layout – see sliding door configurations – and browse the full range of aluminium doors in Gauteng.
Why Gauteng conditions matter
Gauteng’s summer brings heavy thunderstorms and hail, the Highveld sun is strong, and dry winters bring dust. Good aluminium window manufacturers in Gauteng design for that, which puts three things at the top of the list:
- Seals and drainage that keep driving rain out and let water escape from the bottom of the frame.
- A durable finish – powder coating or anodising that stands up to strong sun.
- Laminated safety glass, which holds together if it is broken instead of falling out in shards.
Areas we supply in Gauteng
As one of the aluminium window manufacturers serving the whole province, Coetz™ supplies made-to-order aluminium windows and doors across Gauteng, including Johannesburg, Pretoria, Centurion, Midrand, Sandton, Randburg, Fourways, Roodepoort, the West Rand and the East Rand. See all aluminium windows in Gauteng.
Visit or contact us
Our workshop is at Unit 2, 84 Ridge Road, Laser Park, Johannesburg. We are open Monday to Thursday 07:30–16:30 and Friday 07:30–15:00. Call 010 412 0062, WhatsApp 076 613 4418 or use our contact page.
Aluminium window manufacturers in Johannesburg, Pretoria and the rest of Gauteng
Looking for aluminium window manufacturers in Johannesburg? Our workshop is at Unit 2, 84 Ridge Road, Laser Park, and Pretoria, Centurion, Midrand and the East and West Rand are all on our Gauteng delivery route.
- Buy direct from the workshop: every window and door has a published price online, and collection from Laser Park is free once your order is ready.
- Johannesburg delivery: R650 per order, or R950 if it includes items over 2 400 mm, excluding VAT, in 1–3 working days.
- Pretoria and the rest of Gauteng: R950 per order, or R1 350 with items over 2 400 mm, excluding VAT.
- Doors from the same workshop: sliding, folding, stacking, hinged, pivot and stable doors – see aluminium sliding doors Gauteng and aluminium folding doors Gauteng.
Comparing aluminium window manufacturers on price? Our aluminium windows price list shows real prices for the most popular sizes.
Aluminium window manufacturers: frequently asked questions
Who makes aluminium windows in Gauteng?
Many aluminium window manufacturers operate in Gauteng. Coetz™ makes aluminium windows and doors to order at Laser Park, Johannesburg, and supplies them across Gauteng and nationwide.
Do aluminium window manufacturers install the windows?
Some do and some do not. Coetz™ manufactures and supplies only; your builder or installer fits aluminium windows and doors. MC Automations, our parent company, installs shopfronts and automatic doors.
How long do aluminium window manufacturers take to make windows?
It varies by manufacturer. Coetz™ makes units to order in 1–2 days.
What glass do aluminium window manufacturers use?
It varies. Ask whether safety glass is standard. Coetz™ uses 6.38 mm clear laminated safety glass in every window and door.
Can I collect my windows from the factory?
Yes. You can collect your order free from Coetz™ at Laser Park, Johannesburg, or have it delivered.
Do you make aluminium doors as well as windows?
Yes. Coetz™ makes sliding, stacking, folding, hinged, French, pivot and stable doors, as well as sidelights and toplights.
