In both residential and commercial structures, fire safety is a crucial factor. Using fire doors is one of the most crucial precautions to ensure this safety. In the case of a fire, these doors' unique design prevents smoke and flames from spreading, offering residents and property crucial protection. There are two main types of fire doors: external and inside. They both confine flames, which is their primary role, but their designs, functions, and applications are very different. By being aware of these variations, you may choose the fire doors that are best for your building and guarantee that fire safety laws are followed.
The main differences between interior and outdoor fire doors will be discussed in this article, along with their respective functions in various building types and construction materials and fire ratings.
1. What Are Fire Doors?
Prior to exploring the distinctions between internal and external fire doors, it's critical to comprehend the definition of fire doors and its significance for fire protection. A fire door is designed to withstand fire for a predetermined amount of time, typically 30 or 60 minutes (FD30 or FD60). Fire doors are made to stop a fire from spreading quickly, providing residents more time to leave the building safely and lowering the possibility of property loss. A fire door's efficacy is contingent upon appropriate installation, consistent upkeep, and the use of fire-rated hardware, such as hinges, handles, and seals.
2. The Purpose of Internal and External Fire Doors
Internal Fire Doors
Installed inside a structure, internal fire doors are usually situated between rooms, hallways, stairwells, and other internal areas. These doors are an essential component of compartmentation, which is the process of separating a structure into areas that can withstand fire so that the fire stays where it started.
The primary purpose of internal fire doors is to:
- Prevent smoke and fire from spreading between rooms: This is especially important in multi-room buildings like hotels, apartment buildings, and offices where it can assist confine the fire and reduce damage.
- Establish safe escape routes: Fire doors aid in making sure that escape routes, including stairwells and hallways, are kept clear of smoke and fire for as long as necessary to allow people to leave the building.
UK fire safety standards mandate the use of internal fire doors in specific areas, especially in multi-story structures, to safeguard escape routes, landings, and staircases.
External Fire Doors
Conversely, external fire doors act as a barrier of defense between the building's exterior and interior. They are mostly utilized to stop the fire from spreading into or out of the structure, especially in cases when it may have originated from external sources, even though they also aid in containing the fire.
The purposes of external fire doors include:
- Keeping interior fires contained within the building lowers the danger of property damage and safeguards other structures by keeping the fire from spreading to nearby buildings.
- Preventing the entry of exterior fires: exterior fire doors assist protect the inside of buildings situated close to high-risk regions (such as industrial zones and parking garages) from external fire threats.
External fire doors are legally required in many commercial and industrial premises, and they are frequently put at building exits, such as rear doors or fire escapes.
3. Design Differences Between Internal and External Fire Doors
Construction Materials
One of the main ways that internal and external fire doors differ from one another is the materials utilized in their construction. Both must adhere to strict fire resistance regulations, however the materials chosen vary depending on how they are exposed to various external factors.
- Internal Fire Doors: These doors are often composed of steel, solid wood, or composite materials that have been fire-rated in the center. Internal fire doors don't need to be as weather resistant as external fire doors because they are not subjected to severe weather. Rather than protecting the environment, the materials prioritize durability, smoke containment, and fire resistance.
- External Fire Doors: Made of stronger, more weather-resistant materials, these doors are typically outside and subject to the elements. Because of its strength, fire resistance, and resistance to wind, rain, and UV rays, steel is a common material choice for external fire doors. Certain reinforced composite or aluminum materials that combine weather resistance and fire resistance are used to make external fire doors. Furthermore, weather stripping is frequently included on exterior fire doors to keep moisture out of the structure.
Insulation
Insulation is a further design variation. Compared to internal fire doors, external doors frequently offer better thermal and sound insulation. This is due to the fact that exterior doors must serve as a fire barrier in addition to serving as a barrier against environmental elements like heat, cold, and noise.
- Internal Fire Doors: Compared to its external equivalents, thermal insulation is less of a concern, even though some internal fire doors may provide soundproofing advantages.
- External Fire Doors: Thermal insulation is commonly installed in these doors to help regulate the interior temperature of the structure and save energy. Better insulation also keeps outside noise out of the building, which is why these doors are crucial in crowded cities.
Seals and Hardware
For optimal performance, fire-rated seals and hardware are necessary for both external and internal fire doors, albeit their exact specifications may differ.
- Internal Fire Doors: These doors have intumescent seals installed, which, when heated to a high temperature, expand to form a tight barrier that stops smoke and fire from spreading. Internal fire doors also need to have fire-rated knobs, locks, and hinges. The primary focus is on fire resistance because they are less likely to be exposed to adverse environmental conditions.
- External Fire Doors: To keep out rain, wind, and dust, external fire doors frequently include weatherproof sealing in addition to intumescent seals. To ensure long-term durability, external fire doors also need heavier-duty hardware, like handles and hinges that withstand corrosion. For simpler emergency exits, some external fire doors are further equipped with push bars or panic bars.
4. Functional Differences Between Internal and External Fire Doors
Fire Ratings and Testing
Fire rating systems, often FD30 or FD60, evaluate the fire resistance of both external and internal fire doors over a given time frame. Although the fire ratings are comparable, outdoor fire doors might also go through extra testing to determine how resilient they are to impact, weather, and forced entry.
- Internal Fire Doors: The main test for these doors is if they can resist smoke and fire inside the structure. Impact resistance and weatherproofing are less important because they are not exposed to the outdoors.
- External Fire Doors: Extensive testing is conducted on external fire doors to ensure that they are fire resistant and resistant to environmental elements such as moisture, temperature extremes, and physical damage. By doing this, they can make sure the building is protected from the weather and fire.
Placement and Role
The design and function of internal and outdoor fire doors in a structure are influenced by differences in their placement and purpose.
- Internal fire doors: These doors divide rooms, hallways, and stairwells throughout the structure. Their job is to construct compartments that are resistant to fire, giving building residents safe routes out of the building. Critical spaces with a higher danger of fire, such as server rooms, kitchens, and electrical rooms, are also shielded by internal fire doors.
- External Fire Doors: Found at building exits, external fire doors act as a wall dividing the inside from the outside and keep fires from spreading within the structure. They are essential for emergency egress, guaranteeing the safe evacuation of residents in the event of a fire. External fire doors can be used in industrial settings to divide high-risk areas—like a factory floor from office spaces—from the rest of the building.
5. Regulatory Requirements for Internal and External Fire Doors in the UK
Both internal and external fire doors must meet UK fire safety regulations, which are governed by several key standards, including:
- BS 476: This British Standard outlines the tests for fire-resistance performance of building materials, including fire doors.
- BS EN 1634-1: This European Standard is used to assess the fire resistance of doors and other fire-resistant closures.
The Regulatory Reform (Fire Safety) Order 2005, which stipulates that buildings must be outfitted with suitable fire protection systems, must also be complied with by internal and outdoor fire doors.
Regulations Regarding Internal Fire Doors
Internal fire doors are necessary in residential buildings with more than two stories, primarily to safeguard escape routes such as hallways and stairwells. They are necessary in commercial buildings that have more than one room or that have a high danger of fire.
External Fire Doors Regulations
External fire doors are typically needed at entrances leading to fire escapes or other evacuation routes in commercial and industrial buildings. Additionally, they are required for structures located in places where there may be external fire dangers.
6. Conclusion: Choosing the Right Fire Door for Your Needs
It is essential to comprehend the distinctions between internal and external fire doors when choosing one to ensure both property protection and occupant safety. Although the goal of both types of fire doors is to contain fire, their construction materials, insulating qualities, and hardware are different to suit the situations in which they are used.
While external fire doors protect the building from external fire hazards and provide secure emergency exits, internal fire doors are intended for compartmentalization, safeguarding escape routes, and controlling fire inside the building. Both types of doors must comply with UK fire safety rules, and their efficacy depends on correct installation and upkeep.
You can improve fire safety, safeguard your property, and save lives in an emergency by selecting the appropriate fire doors for your building and making sure they are serviced on a regular basis.
For more information about our interior or exterior doors or door accessories, give us a call at 01603 622261 and speak to a member of our expert team today or Email us at sales@doorsuppliesonline.co.uk. We look forward to hearing from you.