Fire-rated glazing appears on almost every commercial, public and multi-residential project: glazed screens along escape corridors, doors into stair cores, compartment walls between tenancies, sections of curtain walling close to a boundary and glazed roofs over atriums. The drawings usually carry a short code such as EI30 or EI60, but the code alone does not tell a contractor or fabricator everything they need to price and build the element correctly. This article explains what the classes mean, where each one is typically used and what a complete specification should contain.
How fire resistance is classified under EN 13501-2
In Europe, the fire resistance of building elements is classified under EN 13501-2. The classification combines letters for the performance criteria with a number for the time, in minutes, for which those criteria are met in a standard fire test.
- E – integrity: the element prevents flames and hot gases from passing through to the unexposed side.
- I – insulation: the temperature on the unexposed side stays below a defined limit, so materials on that side do not ignite and people can pass close to the element.
- W – radiation: the heat radiated from the unexposed side stays below a defined limit. EW sits between E and EI and is used where full insulation is not required but radiation must be controlled.
- R – load-bearing capacity: the element continues to carry its load. REI is used for elements that are structural as well as separating, such as fire-rated glazed roofs.
The number follows the letters: EI30 means integrity and insulation for 30 minutes, EI60 for 60 minutes, and so on up to EI120. For doors, insulation is further split into I1 and I2 depending on how temperature is measured on the frame and leaf, which is why door schedules sometimes show EI1 30 or EI2 30. Some elements carry split classes, such as REI 30 / RE 45, meaning the element keeps load-bearing capacity and integrity for 45 minutes and adds insulation for the first 30.
Smoke control and self-closing: Sa, S200 and C
For doors, fire resistance is only part of the story. EN 13501-2 also classifies smoke leakage. Sa limits smoke leakage at ambient temperature, while S200 limits it at both ambient temperature and 200 °C. A door that must hold back smoke in a corridor or stair core is typically specified with Sa or S200 added to the fire class, depending on the fire strategy. A self-closing classification (C, with a number for the tested cycles) confirms that the door closes reliably after repeated use.
The Procural PE78EI door and partition family carries smoke control class Sa/S200, and Aluprof MB-60E EI adds smoke control and self-closing class C5 for internal EI30 doors. If the fire strategy requires smoke control, write it into the specification, because a fire door without a smoke class is a different product.
Where EI30, EI60, EI90 and EI120 are typically used
The required class always comes from the national building regulations and the fire strategy for the specific building, so the following is a general orientation rather than a rule.
- EI30 is the most common class for doors and glazed screens along escape routes, between offices and corridors, and in many internal partitions.
- EI60 is often used between larger fire compartments, around stair cores and shafts, and in taller buildings or buildings with more demanding occupancy.
- EI90 appears in more critical separations, such as between different uses in mixed-use buildings or around technical rooms.
- EI120 is reserved for the most demanding compartment walls, for example in large complexes or where a firewall needs to be glazed.
Higher classes mean thicker fire-resistant glass, heavier frames and more complex junction details, so over-specifying is expensive. Under-specifying is worse: an element that does not match the fire strategy will not pass inspection.
Doors, partitions, facades and glazed roofs
Fire resistance is tested and classified for a specific type of element, so a class achieved by a partition does not automatically transfer to a door or a facade built from similar profiles.
Glazed screens and partitions
Procural PE78EI covers EI30, EI60 and EI90 partitions with 35 mm thermal breaks and arched options, and PE78EI Design Line EI120 uses an 89 mm frame with glazing up to 73 mm and heights up to 4 m. PE78EI seamless glass partitions provide EI30 and EI60 with 4 mm joints for an almost frameless look. Aluprof MB-118EI reaches EI120 with a 118 mm five-chamber profile.
Doors
Glazed fire doors are available in PE78EI up to EI90 and in Aluprof MB-78EI from EI15 to EI90, with sound insulation up to 41 dB. Aluprof MB-86N EI provides EI60 doors in a thermally insulated system that also suits external walls.
Facades and curtain walling
Curtain walling near a site boundary or at the edge of a compartment floor may need to be fire rated. Procural PF152EI and PF152ESG EI and Aluprof MB-SR50N EI are available in EI30 and EI60. On a facade the fire can come from inside or outside, so the direction of classification matters and should be confirmed with the fire consultant.
Glazed roofs
Fire-rated glazed roofs are classified with R as well, because they carry load. The Procural PF152EI REI30/RE45 glass roof (slopes from 0° to 80°) and Aluprof MB-SR50N EI for glazed roofs both reach REI 30 / RE 45.
Openable fire windows and smoke vents
Fire-rated windows are often fixed, but some projects need windows that open for cleaning or everyday ventilation. PROCURAL PE78EI EI30 TT is an EI30 tilt-turn window up to 1380 × 2760 mm with sound insulation of Rw 45 dB, and PE78EI EI30 is also available as a fixed window. A fire-rated window is not the same as a smoke vent: smoke exhaust windows open automatically in a fire to release smoke and heat. Aluprof smoke exhaust windows and dampers cover stairwells and atriums.
What to put in a fire-rated specification
A clear specification saves weeks of clarifications during tender. For every fire-rated element, state:
- 1The element type: door, partition, fixed or opening window, curtain wall or glazed roof.
- 2The full classification, including smoke control and self-closing where required, and for facades the direction of fire exposure.
- 3Dimensions and configuration: single or double leaf, side lights, fanlights, overall screen size.
- 4Other requirements: thermal insulation for external elements, acoustic Rw, burglar resistance, access control.
- 5Hardware: closers, hold-open devices linked to the fire alarm, panic or emergency exit hardware.
- 6Finish: RAL colour or anodising, inside and outside.
A fire classification applies to the tested system as a whole: frame, glass, seals, hardware and fixings. Mixing components from different systems or changing the glass type can invalidate it, so keep each element within one system.
The full range of screens, doors, windows, facades and glazed roofs is on our fire-rated systems page, and fire-rated curtain walling sits alongside our other curtain walling systems.
Get help matching systems to your fire strategy
Finestra Solution manufactures fire-rated aluminium systems in Liepāja, Latvia, and has supplied them to projects in Latvia, Denmark, Sweden, Iceland and Spain. Send your drawings, door and screen schedule or fire strategy through our contact page and we will reply within 1–2 working days with a system proposal and a quote. The first project consultation is free.
