Choosing the right bespoke secondary glazing unit:

• Sash windows: Balanced Vertical Slider, or the Tilting version if you want to tilt the panes in for cleaning
• Casements: Hinged, Casement Style glazing
• Wide windows and bays: Horizontal Sliders, from 2 to 5 panels
• Windows you never open: Lift Out, the simplest and most affordable unit in the range

If you’re unsure what type of glazing you need, don’t worry – we’re the manufacturers so simply give us a call and you’ll be talking to the people who build these units. Tell us about the window and we’ll tell you which one suits, including if the best one for you is something cheaper. 

Why choose our premium secondary glazing?

If you have a period home or unusual shaped windows, want an extra-easy install, or simply want the highest quality secondary glazing available – this is the range for you.

You send us the sizes, we build, and the unit arrives ready to install. 

The frame is then pre-drilled for face fixing, the panels are pre-glazed, the gaskets are fitted, and the white PVC trims come in the box to finish the edges cleanly.

The white powder-coated aluminium framework is set into a timber and aluminium sub-frame. That sub-frame takes up the small irregularities between a manufactured, “off-the-shelf” unit and a hand-built opening, which is why we recommend bespoke secondary glazing for period homes: they will sit neatly in a Victorian reveal with a sagging lintel and a sill that isn’t level. 

Choosing your glass specification

As with every aspect of your order – if you’re unsure, call us and we’ll guide you. However here’s a brief breakdown of what the glazing specs mean:

4mm toughened is our standard glazing. It’s safety glass, crystal clear, and what we recommend when you’re mainly dealing with draughts and minor heat loss.

4mm Low E toughened is the same as above, but carries a microscopically thin metallic coating that reflects heat back into the room. This is the best thermal option.

6.4mm laminate is two sheets bonded around an interior layer. Heavier, tougher, and offers better sound insulation than 4mm. Since it’s laminate, it also holds together if broken. 

6.8mm acoustic laminate uses a specialised acoustic interlayer that damps sound rather than just blocking it. Recommended for properties near motorways, railways, flight paths or just a busy street.

Something to note: the air gap matters as much as the thickness. For noise, a wide gap between the existing window and the secondary unit does most of the work. For heat, a narrow gap performs better. 

Measuring and ordering

Measuring is straightforward – see our detailed guide on measuring for made-to-measure glass secondary glazing. 

In brief, however: 

• Measure the width in three places and the height in three places
• Work in millimetres, use the smallest figure of each, and send them exactly as measured. We allow the fitting tolerances when we build

Ordering goes through the quote request form. The prices on this page are sample-size units and exclude delivery, so a quote is the only way to get a real figure. It’s free, and it’s also a second pair of eyes on your measurements before anything is cut.

Because each unit is made to order, lead time is 3 to 4 weeks.

Fitting is within reach of a competent DIYer. Units arrive pre-glazed and pre-drilled, with gaskets fitted and trims supplied. Larger units are heavy and will require two sets of hands. Every product page carries an info sheet (PDF) and fitting videos, and there are real customer installations in our case studies.

Made in North Devon, sold direct

All our bespoke secondary glazing units are manufactured in the UK at our factory in South Molton, Devon. You’re buying from the people who build them, not through a chain of intermediaries.

If you have an unusual window and you’re unsure what will work, or if you’re unsure about anything at all, just ask and we’re here to help.

If needed, send a photo and measurements and you’ll get an honest answer from someone who knows what the machinery can and can’t do, including when a different product would suit you better.