Window and Door Sizes, Glazing and Hardware Options
The practical page: how big we can build, what glass fits what system, and what the hardware looks like. Sizes below are tested or documented maximums, not recommendations — we confirm every configuration against hardware capacity and glass weight before quoting.
What are the maximum sizes you can make?
It varies by system, and it's usually hardware capacity or glass weight that sets the limit rather than the frame.
For our Comet stacker door we build up to 2400mm high by 3600mm wide as a three-panel, and up to 2400mm by 6000mm as a six-panel centre-opening unit. Our Zeus and Ultramax sliding windows run up to 2100mm high by 3000mm wide overall depending on configuration. Hinged door leaves go up to 2600mm high single glazed and 2400mm double glazed, with the width reducing as height increases. Our thermally broken commercial door panels reach 3250mm high.
These are maximums, not recommendations — we'd confirm against your specific configuration before quoting.
How big can a single awning sash be?
It's governed by the stay hardware and the weight of the glass rather than by the frame. Working through our Titan and Apollo stay range, a compact stay suits sashes up to around 300mm high at 8kg, mid-range stays handle up to 800mm at 20kg, and the largest handles sashes up to 1800mm high at 30kg. For casements the limit is width — up to about 1000mm at 40kg on the largest hinge.
On weight we work to roughly 40kg for an awning sash on a hook head, and up to 45kg on our Ultramax awning. Double glazing is significantly heavier than single, so a sash that works single glazed may need splitting when double glazed — worth raising before the design is fixed.
How large can a thermally broken window or door be?
Our 10755 and 160mm thermally broken systems both take door panels up to 3250mm high — hinged and sliding panels in the 10755, stacker panels in the 160mm. For awning sashes in our 160mm system, the stay hardware governs: the compact stay suits sashes to 300mm at 8kg, the mid-range stays to 800mm at 20kg, and the largest to 1800mm at 30kg.
We hold no stated maximum of any kind for our 50mm residential thermally broken system, and no maximum widths or panel weights for any of the three. Double glazed units are heavy, and these systems are double glazed only, so we'd size any large sash against the hardware before quoting.
Do you supply timber reveals?
Yes — roughly 90 per cent of the residential windows we make carry one. A reveal is the timber box lining the wall opening that the window fixes through into the stud work; it hides the installation gap, carries your architraves, seals the frame-to-stud junction and becomes the internal windowsill at the bottom.
Our standard is pre-primed finger-jointed rubberwood at 18mm, with kiln-dried DAR hardwood at 19mm as the premium option. We deliberately don't use MDF — it bubbles on contact with water. Widths run from 100mm to 220mm and we size against your actual wall build-up. The full explanation lives on our replacing old windows guide.
What glass thicknesses can I get?
It depends on the system and whether it's a fixed lite or an opening sash.
For our Comet, Apollo and Titan awning and casement windows, the standard sash takes 4, 5 or 6mm single glazing, 8 to 12mm wet glazed, or double glazed units from 18 up to 24mm. Comet awning fixed lites take 4, 5, 6, 8, 10 or 12mm single glazing, and double glazed units up to 24.76mm. Our sliding window and sliding door sashes take 4, 5 or 6mm single glazing and an 18mm double glazed unit. Our Artemis, hinged door and entry frames accept glass up to 24mm, and our 10055 front glazed commercial system up to 28mm. Our thermally broken systems take 20 to 26mm double glazed units residentially and 24 to 32mm in the commercial ranges.
What's the difference between toughened, laminated and ordinary glass?
Ordinary float glass, also called annealed, is standard glass — it's the cheapest and it breaks into sharp shards. Toughened glass is heat treated to be roughly four to five times stronger and breaks into small blunt granules, which is why it counts as safety glass. Laminated glass is two sheets bonded with a plastic interlayer, so when it breaks it holds together in the frame rather than falling out — and the interlayer also adds acoustic and UV benefits.
Where safety glass is required, both toughened and laminated qualify, but they're not interchangeable in every application. We never substitute annealed glass where toughened or laminated is specified, even if it would physically fit.
What colour hardware is available?
Our standard chain winders come in silver, brown, white, black, primrose and white birch. We also offer a premium winder with a stainless steel chain, available in a black satin finish or powder coated to match your project, with a keyed-alike cylinder.
For sliding windows and doors we fit mortice locks, including a slimline option designed for a more contemporary look. If you're matching hardware across a whole house — including door furniture — it's worth confirming the finish across every system on the job early, since the ranges differ slightly between our window and door systems.
If you have glass in stock that fits, will you use it to save me money?
Only if it's the same specification or genuinely better — never if it's cheaper or lower spec. We keep a stock register, and a piece can only go into your job if it matches on type, appearance and make-up: single for single, double for double, laminated for laminated, the same obscure pattern, the same coating, the same thickness, and toughened where toughened is specified.
The trap is glass that looks identical but isn't. A plain clear double glazed unit and a Low-E one can be visually indistinguishable and the same size, but substituting one for the other throws away the energy performance you paid for and the window's certified rating. We treat a stock piece that prices below the specified line as a warning sign, not a saving.