If you are pricing a window job, the fastest way to get a straight answer is to work from the standard size chart, because aluminium windows sizes and prices in South Africa are tied together. Manufacturers build to a fixed set of standard elevations, and the price of each one is broadly known before anyone measures your house.
This guide sets out the 14 standard sizes you will actually be quoted on, what each one costs as a frame in 2026, and what changes once you add glass and installation. All figures are market ranges gathered from South African suppliers and manufacturers, not a single price list.
Key takeaways
- Standard frames run roughly R600 for a 600 x 600 up to R4,600 for an 1800 x 1800.
- Width is always quoted first, height second. A PT129 is 1200 wide by 900 high.
- Supplied-and-fitted adds around R900 to R2,200 per opening on a like-for-like replacement.
- Custom sizes cost 20 to 40 percent more than the nearest standard and take longer.
- Older Cape Town homes rarely have standard openings, which is why a measured quote beats a shelf price.
What this guide covers
The standard aluminium window size chart South Africa builds to
South African aluminium is manufactured to a shared set of standard elevations. The dominant residential system is the 30.5mm section for top-hung and side-hung windows, with heavier 38mm and sliding sections used on wider spans.
Sizes are expressed in millimetres and always read width first. The industry body for the sector, the Association of Architectural Aluminium Manufacturers of South Africa, sets the technical standards most reputable fabricators build to, which is why a 1200 x 900 from one manufacturer will drop into the same opening as another.
Aluminium windows sizes and prices for 2026
The aluminium windows sizes and prices below cover the 14 elevations that make up most residential work. These are frame prices including standard 4mm clear glass, excluding delivery and installation. Treat them as a planning range rather than a quotation.
| Size code | Width x height | Opening type | Frame price range |
|---|---|---|---|
| PT66 | 600 x 600 | Top hung | R600 – R900 |
| PT96 | 900 x 600 | Top hung | R850 – R1,150 |
| PT126 | 1200 x 600 | Top hung | R1,150 – R1,500 |
| PT156 | 1500 x 600 | Top hung | R1,450 – R1,900 |
| PT186 | 1800 x 600 | Top hung | R1,750 – R2,300 |
| PT69 | 600 x 900 | Top hung | R950 – R1,300 |
| PT99 | 900 x 900 | Top hung | R1,000 – R1,450 |
| PT129 | 1200 x 900 | Top hung | R1,350 – R1,850 |
| PT159 | 1500 x 900 | Top hung | R1,700 – R2,300 |
| PT189 | 1800 x 900 | Top hung | R2,000 – R2,750 |
| PT1212 | 1200 x 1200 | Top hung | R1,650 – R2,250 |
| PT1512 | 1500 x 1200 | Top hung | R2,050 – R2,800 |
| PT1812 | 1800 x 1200 | Top hung | R2,450 – R3,300 |
| PT1818 | 1800 x 1800 | Top hung | R3,400 – R4,600 |
| Ranges reflect bronze and white powder-coated 30.5mm frames with 4mm clear glass, September 2026. Charcoal and bespoke colours carry a premium. Prices exclude VAT variation between suppliers, delivery and fitting. | |||
Ranges compiled from published South African retail and manufacturer pricing, September 2026. For a firm number on your own openings, ask for a measured quote.
How to read the size code on an aluminium windows price list
Quotes rarely spell the dimensions out. They use a code, and once you can read it the whole price list makes sense.
The letters
PT is top hung, PC is a side-hung casement, PS is a sliding window. The letter tells you how it opens.
The numbers
Width then height, in hundreds of millimetres. PT129 is 1200 wide by 900 high.
The section
30.5mm suits standard house openings. 38mm is stiffer and belongs on wide or exposed spans.
The finish
Bronze, white and charcoal are stock. Anything else is a special powder-coat run with a premium.
If a quote lists only “aluminium window” with a price, send it back. Without the size code, section, glass spec and opening type you have nothing to compare against the next quote.
Frame only or supplied and fitted
Buying the frame yourself looks cheaper. Whether it actually is depends almost entirely on how square and how standard your opening is.
Frame only works when
- The opening is already a standard size
- You are replacing like for like in a newer house
- You have a fitter lined up and insured
- You can handle disposal of the old frame
Supplied and fitted wins when
- The house predates 1990 and nothing is square
- The opening needs widening or a new lintel
- You want one party responsible for the seal
- Plaster has to be made good inside and out
On a like-for-like replacement, installation typically adds R900 to R2,200 per opening. That covers removal, disposal, fitting, sealing and making good. Ground floor work with easy access sits at the bottom of that range, upper floors and awkward access at the top.
For a fuller breakdown of installed costs in the Cape market, our guide to aluminium window prices in Cape Town works through supplied-and-fitted numbers on real jobs.
Five things that move aluminium windows sizes and prices
Square metres, not units
Price scales with glazed area. One large window often costs more than three small ones, which catches people out when they open up a wall.
The section weight
Moving from 30.5mm to 38mm adds roughly 15 to 25 percent, and on a 1800mm span it is money well spent.
The glass specification
4mm clear is standard. Laminated safety glass, obscure glass and double glazing each step the price up, sometimes steeply.
How it opens
Fixed panes are cheapest, then top hung, side hung, sliding and folding in that order. Every opening vent adds hardware.
The state of the opening
Dropping a frame into a sound opening is quick. Cutting brickwork, fitting a lintel and re-plastering is a different job at a different price.
Measuring your opening before you ask for prices
You do not need to be exact to get a useful indication, but you do need to measure the right thing.
- Measure the brick opening, not the existing frame. The frame is smaller than the hole it sits in.
- Measure width in three places, top, middle and bottom, and take the smallest.
- Do the same for height, left, centre and right.
- Note which way the window must open, and whether anything outside blocks it.
- Photograph the opening from inside and out. It answers half the questions a fabricator would otherwise have to ask.
Ordering to the size of the old frame instead of the opening. You end up with a window that is too small, and a gap that gets filled with mortar and sealant rather than glass.
We measure on site across greater Cape Town and quote free, with no obligation.
When standard aluminium windows sizes and prices stop working
Standard sizes cover most of the housing stock built after about 1990. Older Cape Town homes are a different story. Steel-window era openings, cottage-pane proportions and anything that has settled over 60 years will rarely land on a standard elevation.
You then have three options. Order a custom size and pay 20 to 40 percent more. Fit the nearest standard down and make the difference up in brickwork and plaster. Or change the opening deliberately as part of a wider job, which is often the sensible choice if you are renovating anyway. Our notes on home renovation costs in Cape Town cover how that folds into a bigger budget.
Material choice matters just as much as size on the coast. If you are still deciding, the comparison of aluminium vs wooden windows covers the long-run cost, and once the frames are in, the coastal maintenance guide explains what salt air does to hardware. You can see completed installations in our project gallery.
Frequently asked questions
What are the standard aluminium window sizes in South Africa?
Standard residential widths are 600, 900, 1200, 1500, 1800 and 2100mm, paired with heights of 600, 900, 1200, 1500 and 1800mm. That gives the 14 combinations most fabricators hold as stock elevations in the 30.5mm section.
How much does a 1200 x 1200 aluminium window cost?
A PT1212 top-hung frame with standard 4mm clear glass runs roughly R1,650 to R2,250 in 2026. Add about R900 to R2,200 for supplied and fitted on a straightforward like-for-like replacement.
Do aluminium windows sizes and prices include the glass?
Usually yes, at 4mm clear. Laminated safety glass, obscure glass and double glazing are extras, and safety glass is a legal requirement in some positions such as low-level glazing and bathrooms.
Can I order an aluminium window in a custom size?
Yes. Expect to pay 20 to 40 percent more than the nearest standard size and to wait longer, typically four to six weeks rather than two to three. For a handful of openings in an older house it is often still the right call.
Is it cheaper to buy the frame and fit it myself?
Only if your opening is already a standard size and genuinely square. If it is not, you will spend the saving on making the hole fit the window, which is the wrong way round and usually leaves a weaker seal.
What is the difference between a 30.5mm and a 38mm section?
The number is the depth of the frame profile. 30.5mm is the standard house section and is fine up to about 1500mm. 38mm is stiffer and holds its shape better on wider spans and exposed elevations, at roughly 15 to 25 percent more.
How long does an aluminium window order take?
Stock standard sizes in bronze or white are often available within a week. Made-to-order standard sizes run two to three weeks, and custom sizes or special colours four to six weeks. Add a day or two for fitting once the units land.
