It is a common misconception in the construction industry that if there is a combustible material in the enclosing structure, then it cannot in any way meet the high requirements for the degree of fire resistance. In fact, this is not the case. If the combustible material is effective in all other important parameters, and the structure is correctly designed and installed, then the system can exhibit the same high resistance to fire effects as a "pie" consisting entirely of non-combustible elements.
This statement has been proven once again at the main test site of the All-Russian Research Institute of Fire Protection of the Ministry of Emergencies of the Russian Federation in Balashikha. The PROOF roofing system developed by PENOPLEX SPb, which includes PENOPLEX OSNOVA thermal insulation, was tested for fire resistance® with flammability group G4. Note that it is possible to use PENOPLEX thermal insulation grades in this roof structure.® with the flammability group G3, but for the purity of the experiment, the least favorable option was taken.
PROOF is a classic roofing system based on profiled metal sheet, which has a long history of successful use at various facilities in almost all regions of Russia. Two samples of the PROOF roof structure with an overall dimensions of 4200 × 2500 × 250 mm and a working span of 4 meters, as well as two samples with an overall dimensions of 6200 × 2500 × 250 mm and a working span of 6 meters, were tested.
In the pictures: a schematic image and a drawing of the PROOF roofing system tested at the test site of the FGBU VNIIPO EMERCOM of the Russian Federation
- Waterproofing based on PLASTFOIL PVC membrane®
- Separating layer - geotextile
- Thermal insulation PENOPLEX BASIS®
- Mineral wool with a density of 70-110 kg / m3, thickness - 50 mm
- Vapor barrier
- The base of the roof is a metal profiled flooring (profiled sheet).
Test preparation
Bench equipment for testing the PROOF system for fire resistance corresponded to GOST 30247.0-94 “Building structures Fire resistance test methods. General requirements . The equipment consisted of a furnace with a fuel supply and combustion system, a device for installing a sample of the roofing system on the furnace, and a system for measuring and recording parameters, including equipment for filming, photographing or video filming.
A metal profiled deck was fixed to the test furnace, on which, in turn, the components of the roof structure were laid according to the installation instructions for the PROOF roofing system.
It should be noted that one of the most important tasks of the test was to verify the operation of the roofing system under extreme conditions. In this regard, a heat-insulating layer of PENOPLEX OSNOVA boards was installed® with a total thickness of 200 mm and a mineral wool cut-off with a thickness of 50 mm. Since samples of load-bearing and self-supporting structures must be tested under load, sandbags were placed on the mounted structure, simulating a snow load of 2.5 kPa (255 kgf / m2), typical for most densely populated regions of Russia. This is practically the maximum load that a profiled sheet base can withstand, taking into account spans of 4 and 6 meters.
Test progress
Pictured: Testing the fire resistance of the PROOF roofing system. Sandbags simulate real snow load
The fire pressure around the perimeter of the furnace was created using nozzles. After one minute, the temperature in the furnace reached 320 ° C, after five minutes it exceeded the 500 ° C mark, ten minutes later it crossed the line of 600 ° C and finally reached 718 ° C. It is these test conditions that are required to confirm the RE15 fire resistance limit, which has previously been held in a similar way on the test benches of other accredited organizations.
After turning off the oven, the system was allowed to cool down without forced extinguishing. This is important in order to once again prove the absence of thermal destruction upon completion of the fire impact.
The fire resistance limit was determined by the time to reach the ultimate deflection of the roofing structure of 200 mm, which was recorded using a deflection meter. The time frame turned out to be acceptable for the use of the PROOF roofing system without additional fire protection with the specified required fire resistance RE15, which was required to be proved.
findings
In addition to confirming the degree of fire resistance of the PROOF roofing system using PENOPLEX® three more important points should be noted.
1. As already mentioned, the tests were carried out at the test site of the head research organization in the field of fire safety: FGBU VNII PO EMERCOM of Russia. This will remove doubts from especially distrustful specialists who are skeptical about the results of tests in other accredited institutions.
2. Samples of the PROOF roofing system were tested with an applied uniformly distributed load of 2.5 kPa (255 kgf / m2). At the moment, there is no information about cases of testing roofing systems with other heaters under such real loads. The tests described here leave no doubt about the effectiveness of the PENOPLEX roofing system.® in real conditions.
3. As already mentioned, two samples of the PROOF roof structure with a working span of 4 m were tested, as well as two samples with a working span of 6 m. Six meters is the maximum possible span for the test furnace of this landfill. This means that the experiment covered all structural options for roofs with the PROOF roofing system, possible for the given test conditions, including the most difficult ones from the point of view of fire resistance.
The main conclusion that allows you to make the test described in the article is a roofing system with a heat-insulating layer of PENOPLEX® and a cut-off made of non-combustible mineral wool has the highest possible fire resistance for structures with a base of profiled metal decking.
