Can you put a vision panel in an existing fire door?
Sometimes, and it depends entirely on the door's certification. Many certificated doors have test evidence covering an aperture up to a stated size and position, in which case a panel can be cut and glazed using the approved system, ideally by a licensed processor or strictly to the door manufacturer's field-of-application. If the leaf has no evidence for an aperture, cutting one destroys its rating no matter how good the glass is. We check the certification first and give you a straight yes or no.
What is the difference between integrity and insulation in fire-rated glass?
Integrity, the E rating, means the glass holds back flame and smoke for the stated period. Insulation, the I rating, means it also limits the heat passing through, so the far side stays survivable and combustibles near the glass do not ignite by radiation. E30 glass in a corridor door holds fire out for 30 minutes but gets ferociously hot; EI30 holds the heat back too. Which one an opening needs comes from the fire strategy, particularly on escape routes where people pass close to the glass.
Why does the beading around fire glass matter so much?
Because in a fire the bead is what holds the glass in the door once the temperature climbs. Tested systems specify the bead material and section, the fixing type and centres, and the intumescent liner or tape between bead and glass; the whole package is what earned the rating. Ordinary softwood quadrant pinned over fire glass looks the same on day one and fails in minutes. It is the single most common fault we find in glazed fire doors, and one of the cheapest to correct properly.
Is wired glass a proper fire-rated glass?
Traditional 6mm Georgian wired glass does carry fire ratings in tested systems and is still legitimate where the system and the certification support it. What it is not is automatic proof of compliance: wired glass in the wrong frame, the wrong bead or an oversized aperture is as much a failure as float glass. Modern clear fire-rated glasses give the same or better performance without the wires, and most replacement work now specifies them because residents and building owners prefer the look.
Do glazed panels need to be a certain size or height in a fire door?
The aperture size and position are limited by the door's test evidence, so the certification is the first constraint. On top of that, doors on accessible routes are expected to give vision at the heights set out in Approved Document M guidance, which is why corridor doors often carry tall narrow panels rather than a small porthole. We set panels out to satisfy both: the certification for fire, the vision zones for people.
Can a glazed screen be fire-rated as well?
Yes. Timber-framed fire-rated screens and borrowed lights are a standard way of getting daylight into corridors and lobbies while keeping the compartment line intact, rated at 30 or 60 minutes to match the wall they sit in. The framing sections, glazing system and fixings all follow the tested detail, and the screen is recorded in the building's fire safety information like any other element of passive protection.
