The recent fire at the Royal Marsden hospital in London has brought into sharp focus the importance of good fire safety procedures and design in our healthcare buildings. Whilst the provision of fire doors, alarms, extinguishers and suitable evacuation procedures is crucial, the influence of building materials on fire safety should not be overlooked. However, this also has to be carefully balanced alongside other needs such as energy efficiency and long term performance.
The Regulatory Reform (Fire Safety) Order, or RR(FS)O, has placed greater responsibility for fire safety on building owners and occupiers, and this in turn has meant increased focus on the fire performance of building materials at the design and specification stage.
Insulation products are no exception as they can have a major impact in helping or hindering fire spread and damage, depending on their own fire performance abilities.
It is worth bearing in mind that insulants vary widely in their makeup and performance and it is crucial not to allow them to be pigeon-holed together, but to look at the performance credentials of each, since the nature of the insulant used in roofs, walls and floors could have a significant impact on the performance of a building. There is also a need for caution and understanding of the different fire classification systems, especially when you realise that some insulation products may actually melt away in the presence of a strong fire, providing little or no fire resistance.
Rigid urethane insulation materials have been successfully assessed under a number of different fire tests. However, there is growing feeling that BS standards, along with the Euroclass ratings, do not offer a full picture of fire performance. Instead, many specifiers and insurers are looking to the test procedures of independent organisations such as the Loss Prevention Certification Board (LPCB) and FM Global.
The LPCB’s LPS 1181 involves largescale insurer approved ‘in-application’ tests that combine assessments of reaction to fire and fire resistance, and can offer a real insight into how a construction will perform under fire conditions. The LPCB also carries out post-test quality checks to ensure that insulation material being manufactured is of the same high quality as the material used in the construction that passed the test.
Apart from its severity, the scale of the test is far greater and far more comprehensive than other procedures.
LPS 1181 compliance is benchmarked against the performance of a building envelope constructed with noncombustible materials, and interfaces such as joints are also examined during the test. Some rigid urethane insulants have successfully undergone LPCB testing; specifically, the LPS 1181 Part 1 test designed to rate the fire performance of external building envelope materials.
Significantly, some rigid urethane products were amongst the first roofing insulation materials to achieve both LPS 1181 Part 1 certification and Factory Mutual (FM) approval. This means that they are capable of providing insurerapproved levels of fire resistance and reaction, in turn minimising fire spread and offering a greater chance of escape for occupants.
Unless a building presents a special fire risk, such as that posed by cooking facilities or other high-temperature environments, fire performance to the LPS 1181 Part 1 EXT-B grade achieved by some rigid urethane products is widely considered to offer more than adequate protection in the case of fire.
However, in these sustainabilityconscious times, we must also consider the environmental impact of products in balance with fire safety.
Rigid urethane insulants do not compromise other key performance areas and are in fact amongst some of the most thermally efficient products on the market. For example, rigid urethane roofing products with LPS 1181 Part 1 approval can provide U-values as low as 0.10 W/m2K if installed correctly and with the lowest possible thicknesses.
Furthermore, these materials are not prone to performance-inhibiting problems such as poor resistance to foot traffic, moisture ingress or air movement which can seriously affect the thermal efficiency of other insulants.
Fire safety is a vital factor in building material specification, and great care should be taken that products are tested and approved by widely recognised standards and procedures. In achieving LPS 1181 Part 1 approval, some rigid urethane insulation materials can provide more than adequate fire performance, whilst not forsaking other key requirements such as energy efficiency, providing the all-round performance that is so important in today’s climate.
