BS EN 1279 is the European standard that governs the manufacture and performance of insulating glass units (IGUs) — the sealed double or triple glazed units fitted into window and door frames.
The standard is split into six parts, each covering a different aspect of sealed unit quality. Parts 2 and 3 deal with moisture penetration and gas leakage — the two failure modes that cause misted, foggy, or blown double glazing. Parts 5 and 6 cover the factory production controls and conformity assessment that ensure every unit meets the same standard.
When you buy from Pane Relief, you're getting units that have been independently tested against these standards. This matters because non-certified units may use inferior sealants, thinner spacer bars, or skip argon gas fill — all of which reduce the lifespan and thermal performance of your glazing.
Our Bristol factory maintains full traceability from raw glass to finished unit. Every sealed unit can be tracked back to its component materials, manufacturing date, and quality checks. This traceability is a requirement of BS EN 1279-6 and is what allows us to back our products with a genuine 10-year warranty.