How to Select the Appropriate Thickness of Sandwich Panels
I. Selection Based on Application Scenarios
Building Exterior Walls and Roofs
- Ordinary Buildings: Generally, sandwich panels with a thickness of 50 - 100 mm are selected. For example, EPS sandwich panels with a thickness of 50 - 80 mm can be used for ordinary residential buildings.
- Cold Regions or Cold Storages: A thickness of 100 - 150 mm is required. For example, polyurethane sandwich panels with a thickness of 120 - 150 mm can be used for cold storages.
- Large Industrial Plants: Sandwich panels with a thickness of 80 - 120 mm can be selected. Rock wool or glass wool cores are suitable choices.
Interior Partition Walls
- Non-load-bearing Partition Walls: Lightweight sandwich panels with a thickness of 30 - 50 mm are sufficient, such as EPS sandwich panels.
- Fire-resistant Partition Walls: The thickness should be ≥50 mm, and rock wool cores are preferred.
Clean Rooms and Fire-prone Areas
- Clean Rooms: Sandwich panels with a thickness of 50 - 80 mm can be selected, and polyurethane or rock wool cores are better choices.
- Fire-prone Areas: It is recommended to use sandwich panels with a rock wool core and a thickness of ≥100 mm.
II. Consideration of Structural Load Requirements
Merely as Enclosure Structures
When not bearing loads, thin sandwich panels with a thickness of 30 - 50 mm can be selected, such as EPS sandwich panels.
Need to Bear Loads
When subjected to equipment or live loads, sandwich panels with a thickness of ≥80 mm and high strength should be selected. Sandwich panels with rock wool or cement fiber cores and a core material density of ≥120 kg/m³ are suitable.
III. Consideration of Thermal Performance
Cold Regions
In regions like Northeast China, sandwich panels with low thermal conductivity should be selected, and the thickness should be ≥100 mm. Core materials such as polyurethane or extruded polystyrene can be chosen.
Hot Regions
Sandwich panels with a thickness of 60 - 80 mm and a rock wool core can be selected to take into account both heat insulation and fire resistance.
Reference Standards
According to standards such as the "Code for Thermal Design of Civil Buildings", the heat transfer coefficient of exterior walls in cold regions should be ≤0.4 W/(m²·K), corresponding to a total thickness of the sandwich panels of about 100 - 120 mm.
IV. Consideration of Installation Environment and Climate
High-humidity or Coastal Areas
Sandwich panels with corrosion resistance should be selected, and the thickness should be ≥80 mm. For example, a combination of glass magnesium boards and rock wool cores or galvanized treatment can be used.
Areas with Large Temperature Differences
Sandwich panels with a thickness of ≥100 mm and a core material density of ≥150 kg/m³ should be selected to reduce deformation.
Areas with Strong Winds or Heavy Snow Loads
The rigidity should be increased, and sandwich panels with a thickness of ≥120 mm should be selected to resist external forces.
V. Consideration of Economy
Balance between Cost and Performance
For every 10 mm increase in thickness, the cost increases by 15% - 20%. Make a trade-off and then select.
Transportation and Construction Costs
Excessive thickness increases transportation and hoisting costs. Avoid excessive thickness.
VI. Reference to Standards and Manufacturer Parameters
International Standards
ASTM C55 recommends that the roof panel thickness be ≥6.35 mm and the wall panel thickness be ≥12.7 mm, which are for reference only.
Chinese Standards
GB/T 23932 specifies the thickness range of sandwich panels according to different uses, which should be followed.
Manufacturer Parameters
Due to factors such as different core materials, the performance of sandwich panels from different brands varies. Manufacturer's manuals can be referred to for selecting the thickness.
In conclusion, when selecting the thickness of sandwich panels, multiple factors need to be comprehensively considered to ensure the quality and effect of the project.
