They weren't a bad choice when they went in — but seals perish, the argon gas in older units slowly leaks out, and hardware loosens. A double-glazed window from two decades ago is doing a fraction of the job a current triple-glazed unit does, even though nothing looks obviously "broken" about it from the inside.
Genuinely single-glazed timber units do still turn up occasionally — usually in older properties that have never been touched — but they're the exception now, not the rule. For most homes, the real upgrade isn't single-to-double, it's swapping out tired double glazing for triple.
Most jobs come down to a mix of these — knowing roughly what you want before we visit helps us scope the right spec from day one.
Triple glazing as standard now — on the WDS profile system we fit, that's a 0.79 W/m²K U-value and up to 38dB sound reduction (50dB with acoustic glass), well ahead of the double glazing it's replacing.
76mm, 6-chamber PVC profile with a 3-level gasket seal — built for UK weather, not just a thinner budget frame with triple glass squeezed in.
Multi-point locking as standard, with reinforced door profiles built specifically for the loads a front or back door takes day to day.
Lamination finishes beyond plain white, so a triple-glazed upgrade doesn't have to mean going back to the "white PVC" look if that's not what suits the property.
The windows we fit use the WDS 76 MD profile system — a 76mm, 6-chamber PVC profile with a 48mm triple-glazed unit. The figures on the right are WDS's own published specification for that system. The figures on the left are typical for double glazing installed 15–20 years ago, not a measurement of your specific windows — we'll confirm your exact starting point on a site visit.
Tell us how many windows and doors you need replacing — every quote is built on triple-glazed WDS PVC profile units as standard. Final pricing follows a site visit and exact measure-up.
Book a consultation and we'll talk through the right glazing, frame and security spec for your property.
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