In older terraced houses the attic can be a single open space, extending from one end of the building to the other. This means that a fire in one flat can spread to the entire building through the attic. The end result may be total destruction. The Finnish National Rescue Association (SPEK) recommends that all open space attics in so far unsectioned terraced houses be sectioned with fire resistant structures.
Fires in terraced houses often progress so that the heat breaks a window through which hot fire gases and smoke break out, accumulating at first under the eaves. Then they make their way into the attic. If the attic is not sectioned with smoke proof structures, the entire attic space fills with smoke.
The fire can also break through a flat’s ceiling and spread directly into the attic. When there is enough hot smoke, the attic catches fire along its entire length.
This may be the case, particularly, in houses built before October 1990. The building code for terraced houses built after that requires sectioning of individual flats in such a manner that their adjoining walls extend all the way to the roof. Such sectioning delays the spread of fire for at least 30 minutes and the fire cannot easily spread from one flat to another through the attic. Sectioning also makes firefighting easier.
On average, approximately 300 terraced houses catch fire in Finland each year and news of totally destroyed terraced houses is not rare.
Therefore, SPEK recommends voluntary attic sectioning renovations for all such terraced houses where this has not yet been implemented.
Sectioning can be achieved after construction, for example, by installing suitable solid, flameresistant side shields on roof trusses. It is also important to tightly pack the insulation against the roofing material at the top.
When needed, soft mineral wool can be used to achieve this. Then the smoke cannot make its way around the insulating sheets to spread the fire. Sectioning, or the lack of it, can be checked by peeking into the attic. If it is possible to see both of the end walls through the building, sectioning is inadequate by modern safety standards.
– The easiest way to incorporate the change is when it is done during a roof renovation, at which time it is possible to tightly insulate even the low end spaces of the attic. At best, it is possible to section the attic at each flat’s adjoining walls, akin to new construction.
However, since this is a voluntary measure, it may not necessarily achieve the same standard as new buildings. Still, any sectioning in the attic will improve safety, hints Ilpo Leino, Head of Security, Finnish National Rescue Association.
What is the Fire Prevention Technology Development Group?
The Fire Prevention Technology Development Group is a group of experts whose shared goal is to advance safety and to develop the service and maintenance, qualityand technical prospects of fire prevention technology. The environment is constantly developing and fire prevention must stay up-to-date to meet the new challenges.
The Finnish National Rescue Association, SPEK
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