Fire technical challenges in the reconstruction of balconies and passageways

Renovation projects can be made more difficult and more expensive if fireproofing is not incorporated from the very start. But what are the fire requirements with regard to the reconstruction of balconies and passageways, and how can these requirements be met?

More dwellings in the cities and better, more energy-friendly dwellings with new opportunities. These are two of the trends that characterize the renovation and reconstruction of existing apartment blocks in, for example, Copenhagen and the Jutland city of Aarhus where the bulk of the housing stock is of a considerable age.

However, the reconstruction of existing properties can throw up a range of fire technical challenges. Not least the fact that there are two types of reconstruction, says fire technical consultant Allan Anton Hansen from DBI: The covering of balconies and the covering of passageways.

Establishing which fire requirements come into play in such projects can be a complex task. But, as a rule, in the case of outright reconstructions, including significant changes of use, the same rules as for new builds apply. In the case of renovation the requirement is that the building’s existing level of safety must be maintained.

However, it’s not always that simple, says Allan Anton Hansen, who regularly advises architects, engineers and developers who have come up against unforeseen challenges with regard to fire safety requirements in reconstruction projects.

The covering of passageways and balconies is a popular reconstruction project. A balcony enclosed by glass gives the apartment a sunroom or an extra space and a covered passageway reduces the building’s energy consumption and provides protection against rain, snow and the wind at the entrance to the apartments.

– Both types of reconstruction will normally throw up new requirements for fire safety. For example, in practice a covered balcony becomes a new room in the dwelling which is why the balcony floor must comply with the same fire requirements as the storey partition itself. Otherwise, the level of safety is reduced, explains Allan Anton Hansen.

The spread of fire via the passageway
Likewise, a covered passageway can reduce the level of fire safety if particular attention is not paid here. This is because there is normally no fire segregation between the apartments and the open passageway.

– Consequently, a covered passageway can lead to the fire spreading between the apartments through the unclassified building components. In an open passageway there is less risk of a fire spreading from apartment to apartment but the risk increases when the passageway is covered, explains Allan Anton Hansen.

At the same time, passageways often function as the primary access route for the emergency services in the event of a fire and, naturally, this function should also be maintained.

Incorporate fire safety in the early stages
Fire safety can either be documented by using the prescriptive solutions specified in “Eksempelsamling om brandsikring af byggeri 2012” (“Collection of examples on the fireproofing of buildings, 2012″) or by means of calculations/fire technical dimensioning.

In any event, it is important that fire safety is incorporated in the early stages of the project. This is both in interest of cooperation between the building regulatory authorities who have to approve the project and also to avoid the need for redesigning in the late stages of the project – or quite simply altering the work that has been completed, examples of which we see every now and then, Allan Anton Hansen explains.