Fire-Rated Glass: Integrity vs Insulation
Fire-rated glass is glazing tested to keep a fire compartment intact for a stated time. An integrity (E) rating means it stops flames and smoke passing; an insulation (EI) rating also limits the heat transmitted to the protected side, so people can pass close to it during a fire.
By Dhruv Agarwal · · 1 min read
Why it matters
Glass walls along corridors, stairs and lobbies often sit on fire compartment lines. There, ordinary glass would fail within minutes; fire-rated glazing keeps the compartment intact long enough for people to escape.
How it works in practice
| Rating | Stops flames & smoke | Limits heat | Typical use |
|---|---|---|---|
| E (integrity) | Yes | No | Where people do not pass close by |
| EI (insulation) | Yes | Yes | Escape routes, adjacent occupied areas |
Common mistakes
- Rated glass in an unrated frame. The system, not the glass, carries the rating.
- E where EI is needed. Heat on escape routes can be dangerous.
- Unrated penetrations through fire-rated glass walls.
Standards referenced
Fire resistance classification under EN 13501-2. Compartmentation under NBC 2016, Part 4.
Standards referenced
- EN 13501-2 — Fire resistance classification
- NBC 2016, Part 4 — Fire and life safety — compartmentation