Insulation materials for factory buildings
PE foam, PU panels and air bubble insulation are three common solutions for lowering the temperature inside metal-roofed factories, improving working conditions for workers and cutting the operating cost of cooling systems.
In summer, an uninsulated metal roof can reach 65 to 70 °C, pushing the temperature inside the factory below it above 38 °C. This reduces labor productivity and affects machinery and heat-sensitive materials such as adhesives, plastics and electronic components.
How heat passes through the roof
Solar heat enters the factory mainly through radiation from the underside of the hot metal sheet. Insulation materials need both low thermal conductivity and a reflective surface to block radiant heat.
Comparing insulation materials
| Material | Thermal conductivity | Heat reflectance | Key advantage |
|---|---|---|---|
| Foil-faced PE foam | Approx. 0.035 – 0.040 W/m·K | Approx. 95% with aluminum facing | Lightweight, easy to install, reasonable cost |
| Rigid PU panel | Approx. 0.020 – 0.025 W/m·K | Depends on facing | Best insulation, rigid |
| Air bubble insulation | Depends on the air layer | Approx. 95% with aluminum facing | Thin, inexpensive, some sound insulation |
| Glass wool | Approx. 0.035 – 0.045 W/m·K | With foil facing | Good fire resistance, sound insulation |
Selection by building type
- Factory renovation: foil-faced PE foam 5 to 10 mm thick, installed under the metal sheet without removing the roof.
- New factories: PU sandwich panels or metal sheets with spray-applied PU on the underside.
- Cold storage and cleanrooms: PU panels 50 to 150 mm thick.
- Factories with strict fire safety requirements: glass wool or fire-retardant PE.
Installation tips for best results
The foil side should face an air space with a gap of at least 2 cm to take full advantage of its reflectivity. Panel edges should be overlapped and sealed with aluminum tape to prevent thermal gaps and condensation, which causes water to drip from the roof onto the floor during humid spells.
Combining roof insulation with exhaust fans and evaporative cooling can lower the factory temperature by an additional 5 to 8 °C compared with using a single solution.
In terms of cost, the investment in roof insulation typically pays for itself within a few summers through reduced cooling energy, especially for air-conditioned workshops or warehouses that must maintain stable temperatures for raw materials. It is an investment many plant owners prioritize when renovating older factories.
Contact AMS Vietnam for a site survey and advice on the right insulation materials for your factory.
