How to transform a warehouse with PVC roof into a Class A warehouse with a second-level fire resistance rating

\"Code for Fire Protection Design of Buildings\": Some of the requirements are as follows: Buildings with a fire resistance rating of Class II have a mixed structure consisting of steel structural roof trusses, reinforced concrete columns, or brick walls； 3.2.12 Except for Class A and B warehouses as well as high-rise warehouses, for the non-load-bearing exterior walls of buildings with fire resistance ratings of Class I or II, when non-combustible walls are used, their fire resistance limit shall not be less than 0.25 hours ； When non-combustible walls are used, it should not be less than 0.50 hours. For the non-load-bearing exterior walls of above-ground factories (warehouses) with fire resistance ratings of Class 1 or 2 and belonging to Fire Classes D or E, with 4 floors or fewer, the fire resistance limit is not restricted when non-combustible wall materials are used. 3.2.13 For the partition walls in rooms within factories (warehouses) with a secondary fire resistance rating, if flame-retardant walls are used, their fire resistance limit shall be increased by 0.25 hours. 3.2.14 In multi-story factories and warehouses with a secondary fire resistance rating, floor slabs made of prestressed reinforced concrete shall have a fire resistance limit of not less than 0.75 hours. 3.2.15 For the walkable flat roofs of factories (warehouses) with fire resistance ratings of Class I and Class II, the fire resistance limit of their roof panels shall be not less than 1.50 hours and 1.00 hour respectively. 3.2.16 The roof panels of factories (warehouses) with fire resistance ratings of Class I and II shall be made of non-combustible materials. The roof waterproofing layer should be made of non-flammable or flame-retardant materials. When flammable fireproof materials are used and laid on flammable or flame-retardant insulation materials, a non-flammable material should be used as a protective layer for either the waterproofing material or the flammable/flare-retardant insulation material.

Steel beams and steel purlins are coated with fire-retardant paint, achieving a fire resistance limit of 1 hour. The roof panel uses a lightweight steel roof, with fire-resistant materials such as glass wool or rock wool used in the insulation layer.