The footnotes to Annex 4 of the Turkish Regulation on Fire Protection of Buildings (BYKHY) either double the compartment area (accommodation, healthcare, offices) or make it unlimited (education, commercial, food and drink, assembly, industrial buildings, storage) when suitable fire control systems such as automatic detection, a sprinkler system and a smoke extraction system are installed. Enclosed car parks have no limit in any case, and dwellings are already unlimited.
Annex 4 footnotes
- (1) If suitable fire control systems (automatic detection, sprinkler system, smoke extraction system and the like) are installed, the compartment area may be doubled.
- (2) If suitable fire control systems are installed, the compartment area is unlimited.
- (3) If the building is single-storey, there is no limit. If suitable fire control systems are installed, the compartment area is unlimited.
Without and with systems
| Use class | Annex 4 limit (m²) | Footnote | With suitable fire control systems |
|---|---|---|---|
| Dwellings | Unlimited | Unlimited | |
| Accommodation | 4,000 | (1) | 8,000 |
| Healthcare | 1,500 | (1) | 3,000 |
| Educational facilities | 6,000 | (2) | Unlimited |
| Office buildings | 8,000 | (1) | 16,000 |
| Commercial | 2,000 | (2) | Unlimited |
| Food and drink, entertainment, museums and exhibition venues | 4,000 | (2) | Unlimited |
| Other assembly buildings | 6,000 | (2) | Unlimited |
| Industrial, Ordinary Hazard-3 and above | 6,000 | (2) | Unlimited |
| Industrial, Ordinary Hazard-1 and 2 | 15,000 | (3) | Unlimited (already unlimited if single-storey) |
| Storage, Ordinary Hazard-3 and above | 1,000 | (2) | Unlimited |
| Storage, Ordinary Hazard-1 and 2 | 5,000 | (3) | Unlimited (already unlimited if single-storey) |
| Enclosed car parks | No limit | No limit |
Practical example: 50,000 m² logistics warehouse
In a warehouse of the Ordinary Hazard-3 and above class without suitable fire control systems, the Annex 4 limit is 1,000 m²; 50,000 m² would need 50 compartments. When suitable fire control systems are installed, footnote (2) makes the area unlimited and the warehouse can be planned as a single open volume. This flexibility removes the area limit in Annex 4, not the compartment continuity requirement of Article 24(7); enclosed spaces with a fire hazard (Article 24(2)) must still be separated.
Field note
The footnote text says "automatic detection, sprinkler system, smoke extraction system and the like" (unofficial translation); in other words, it lists the systems as examples. According to the explanation in the Guide, it is not mandatory to plan all the systems listed in the footnote; the relevant fire brigade unit assesses, under the relevant articles of the Regulation, which fire control systems are needed according to the building's characteristics, such as its height, area and the materials used or stored. The generalisation "all three are required" is therefore not correct; one of the suitable fire control systems in the footnote is sufficient; the systems on which an increased limit relies should be written into the project report with their justification, and the fire brigade's opinion should be obtained at an early stage. For the design standards of these systems, see the BYKHY articles on sprinklers (Article 96), detection (Article 75) and smoke control (Article 85 onwards).
Checklist
- Have the use class and footnote number been read correctly from Annex 4?
- Have the fire control systems on which the increased limit relies been shown in the project with their justification, and has the assessment of the relevant fire brigade unit been obtained?
- In accommodation, healthcare and offices, has the doubled limit not been exceeded (footnote 1)?
- Have enclosed spaces with a fire hazard been separated (Article 24(2))?
- Has the compartment continuity requirement been maintained (Article 24(7))?
FAQ
Does the compartment area become unlimited if sprinklers are installed?
Under the Annex 4 footnotes, if suitable fire control systems (automatic detection, sprinkler system, smoke extraction system and the like) are installed, the compartment area is unlimited in the education, commercial, food and drink, assembly, industrial and storage classes; in accommodation, healthcare and office buildings it may be doubled. The footnote lists these systems as examples; according to the explanation in the Guide, it is not mandatory to plan all of them together, and the relevant fire brigade unit assesses which systems the building needs.
What is the compartment area in an office building?
In Annex 4 the maximum compartment area for office buildings is 8,000 m²; under footnote (1) it may be doubled with suitable fire control systems, that is, to 16,000 m². It does not become unlimited.
Is there a limit for a single-storey warehouse?
Footnote (3) applies to Ordinary Hazard-1 and Ordinary Hazard-2 storage buildings and industrial buildings: if the building is single-storey there is no limit; it is also unlimited if suitable fire control systems are installed.
References
- Turkish Regulation on Fire Protection of Buildings (BYKHY), Official Gazette 19.12.2007/26735 and amendments; Articles 24, 75, 85, 96, Annex 4. mevzuat.gov.tr
- Guide to the Regulation on Fire Protection of Buildings (Ministry of Environment, Urbanisation and Climate Change, General Directorate of Professional Services, r2, December 2024), explanation of Article 24(6).
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Download MEP Calc on the App StoreSources are listed in the References section at the end of the article. Quotations from the regulation are unofficial English translations of the Turkish text. This article is for general information; for article numbers, thresholds and exemptions, the current regulation and standard texts published in the Official Gazette govern, and design must be carried out by an authorised engineer.