Over the last number of years’, legislation, standards and recommendations regarding fire-rated doors have become nothing short of complicated.
A door is a door, right? While it may seem simple, countless considerations have gone into the selection, manufacturing and positioning of the fire door in your office building (probably currently being propped open by a fire extinguisher). What is the building used for? Do vulnerable people need to be considered? Does the door form part of an escape route? Will the door incur heavy use? What are the fire risks in the immediate area? Is the door part of a fire compartmentation plan?
These are just some of the questions that are asked when choosing an appropriate door. Once the required door ratings, design, hardware and action types are confirmed, architects / contractors must ask themselves their next big question, to use a pre-hung door set or not?
How are fire doors certified?
Before deciding which option to choose, it is beneficial to understand the certification process for fire doors. For a fire door to gain certification, it must be tested by an approved test facility. When testing, it is not just the door leaf itself being tested, but also the frame, the hinges, the intumescent seals, the hardware and any other associated equipment or glazing. The British Standards Institute states that “fire resistance is a property that can be possessed only by a complete construction”.
These tests are often completed several times, using variations of hardware and glazing in different locations and sizes across the door and the frame. As long as the door lasts longer than its required rating time e.g. 30 minutes, the door has passed the test in this configuration. A test report will then be compiled for each door test, essentially detailing the time the fire breaches the door and the location of this breach.
Test reports are then provided to a certification body, such as the BBA or BRE, who begin the process of writing a single global certification document and design guide for the door. This will specify details such as the minimum and maximum size of the door leaf and glazing, acceptable frame materials, intumescent seal types, hardware configurations and approved manufacturers. It is this document that companies such as Loughview Timber use when designing and assembling these fire rated door sets.
What is a pre-hung doorset?
As you’ve probably guessed by now, a pre-hung door set is a door that has all the associated hardware and fire-stopping assembled and is pre-hung in a frame that was designed to fit a specific structural opening.
The British Standards Institute (the guys who set out the criteria for testing fire doors) define a doorset as “an assembly (including any frame or guide) for the closing of permanent openings in separating elements.”
The LPCB (the people you want to keep happy to ensure your building is insured!) state that “the term fire door comprises any doorset … including any frame or guide, door leaf or leaves… etc., which is designed to give a fire-resisting capability when used for closing off permanent openings in separating elements of construction. This includes any side panels, vision panels, or transom panels together with the door hardware and any seals which form the assembly.”
The benefits of pre-hung doorsets
So back to our original big question, to use a pre-hung doorset or not? Hopefully, the title of our article and what we’ve discussed so far has given a strong enough indication as to our recommendation. We recommend pre-hung door sets in all but the most exceptional circumstances.
It’s not just us however, the British Standards Institute recommend that “Ideally, fire doors should be purchased as coordinated assemblies in accordance with the manufacturer’s specification … to ensure that all the correct components are fitted” and “In the case of a fire door, it is only the complete assembly as described in the relevant fire test report that can be deemed to provide the required performance”.
We are always surprised by the number of customers who ask us for individual components and a separate door leaf, to self-assemble the door set. If you are not listening to the BSI’s advice, at least consider some of the below benefits:
- Cost and Efficiency – Although buying components separately may be cheaper initially, this will impact project costs and efficiency in the medium to long term. Once you have the components, specialist skills are required to assemble and fit the doors. Doorsets are built to spec, making them faster and easier to install.
- Compliance – As discussed previously, door sets are tested, manufactured, then installed as complete units. This helps ensure their fire and security performance; in addition, each door set will be provided with a certificate, evidencing compliance.
- Quality – Certified manufacturers of door sets are subject to factory production control audits from organisations such as the BBA, to ensure a consistent quality of output, in line with regulatory requirements. Manufacturers such as Loughview Timber, which hold ISO9001 certification, will also have internal audit procedures, ensuring customer needs and quality requirements are consistently met.
- Environmental Concerns – With specialised equipment and machinery, wastage is kept to a minimum throughout the production line and waste products such as sawdust and offcuts are reused.
- Management – As the door set and all its components are coming from one manufacturer, managing the purchasing process, from ordering and finance through to customer support, is much easier.
When specifying doors for your project, use pre-hung doorsets for peace of mind.