The roof thickness of the pool is generally not less than 30 cm. According to the design requirements, the roof thickness of the fire pool is generally not less than 250mm, and the non-load bearing is generally10-15 mm. It is also very necessary to line the roof with FRP. The function of epoxy glass fiber reinforced plastic lining is waterproof, anticorrosive and mildew-proof. If the roof is not lined, these functions will lose their function to varying degrees. We know that after the water in the pool evaporates, many small water droplets will condense on the roof, and these water droplets will densely cover the roof. When they are big enough, they will fall back into the pool because they can't bear their own gravity, and the roof will always be wet. First of all, from the perspective of waterproofing, the roofs of many pools are the floors of the rooms above. If the roof of the pool is always wet, the floor of the room above will be wet, so the roof of the pool must be lined with epoxy FRP. Secondly, from the aspect of anti-corrosion, because the roof is wet, it will gradually corrode the reinforced concrete, and the roof will gradually lose its strength and be in danger of collapse. Therefore, it is necessary to line the roof with epoxy FRP.