Sandwich Panel Weight Calculator

Professional estimation for construction logistics and structural loading

Accurately estimating the dead load of building materials is critical for structural engineering, logistics planning, and installation safety. This sandwich panel weight calculator is designed to provide precise weight estimations for composite panels used in roofing, wall cladding, and cold storage construction. Whether you are working with PIR, Mineral Wool, or EPS cores, understanding the specific weight per square meter is essential for designing supporting structures and calculating shipping requirements.

What is a Sandwich Panel Weight Calculator?

A sandwich panel weight calculator is a specialized digital tool used by architects, engineers, and construction managers to determine the total mass of composite panels. A sandwich panel (or composite panel) consists of three layers: a low-density core inserted between two relatively thin skin layers. This combination allows for high structural rigidity with low weight.

This tool helps professionals avoid common pitfalls such as underestimating roof loads or overloading transport trucks. It takes into account the different densities of core materials (like mineral wool vs. polyurethane) and the thickness of the metal facings (steel or aluminum).

Sandwich Panel Weight Formula and Explanation

The calculation of sandwich panel weight is based on the summation of the weights of its individual components. The general formula used in this calculator is:

Total Weight = (Weight of Skins) + (Weight of Core)

To derive the weight per square meter ($kg/m^2$), we use the following detailed mathematical approach:

Variable Definitions for Weight Calculation

Variable	Meaning	Unit	Typical Range
$t_{skin}$	Skin Thickness	mm	0.4 – 0.7 mm
$\rho_{skin}$	Skin Density	kg/m³	7850 (Steel), 2700 (Alum)
$t_{core}$	Core Thickness	mm	40 – 200 mm
$\rho_{core}$	Core Density	kg/m³	40 (PIR), 100+ (Rockwool)

Since there are two skins (internal and external), the formula for Area Weight ($W_A$) is:

W_A = [ 2 × (t_skin / 1000) × ρ_skin ] + [ (t_core / 1000) × ρ_core ]

Practical Examples

Example 1: Cold Storage Warehouse (PIR Core)

A logistics center requires 100mm thick PIR panels for thermal insulation.

• Panel Size: 6m x 1m
• Skins: 0.5mm Steel (Density 7850 kg/m³)
• Core: 100mm PIR (Density 40 kg/m³)

Calculation:
Steel Weight = 2 × 0.0005m × 7850 = 7.85 kg/m²
Core Weight = 0.1m × 40 = 4.00 kg/m²
Total Area Weight = 11.85 kg/m²
Total Panel Weight = 11.85 × 6m² = 71.1 kg

Example 2: Fire-Resistant Partition (Mineral Wool)

A factory firewall uses Mineral Wool panels for fire resistance.

• Panel Size: 4m x 1m
• Skins: 0.6mm Steel
• Core: 150mm Mineral Wool (Density 120 kg/m³)

Calculation:
Steel Weight = 2 × 0.0006m × 7850 = 9.42 kg/m²
Core Weight = 0.15m × 120 = 18.00 kg/m²
Total Area Weight = 27.42 kg/m² (Significantly heavier due to core density)
Total Panel Weight = 27.42 × 4m² = 109.68 kg

How to Use This Sandwich Panel Weight Calculator

1. Enter Dimensions: Input the length and width of a single panel, and the total quantity required.
2. Select Skin Material: Choose the facing material (usually Steel). Input the thickness in millimeters (e.g., 0.5).
3. Configure Core: Select the insulation type. The calculator defaults the density based on the material (e.g., 40 for PIR), but you can edit this if your manufacturer provides specific data.
4. Review Results: The tool instantly calculates the total batch weight and weight per square meter.
5. Analyze Breakdown: Use the chart to see if the weight is driven by the steel skin or the heavy core.

Key Factors Affecting Results

Several variables can influence the final calculation of your sandwich panel weight:

• Core Density: Mineral wool is roughly 3x heavier than PIR/PUR foam. This drastically changes the dead load on the structure.
• Skin Thickness: Increasing steel thickness from 0.4mm to 0.6mm increases the panel weight by roughly 3 kg/m².
• Profile Geometry: This calculator assumes flat sheets. Deeply profiled roofing panels contain more steel per square meter of coverage width (up to 15-20% more), increasing the actual weight.
• Adhesives: The glue layer adds a small amount of weight (approx 0.1-0.3 kg/m²), which is often negligible but present.
• Moisture Absorption: While closed-cell foams (PIR/EPS) resist water, open-fiber cores like mineral wool can gain significant weight if they absorb moisture during storage.
• Tolerance: Manufacturing tolerances in steel thickness can result in +/- 5% weight variations.

Frequently Asked Questions (FAQ)

1. Does this calculator include the weight of flashings and screws?

No, this sandwich panel weight calculator estimates the panel mass only. Fixings and flashings typically add 1-3% to the total cladding weight.

2. What is the standard density for PIR panels?

Polyisocyanurate (PIR) typically has a density between 38 and 45 kg/m³. A safe estimation value is 40-42 kg/m³.

3. How much heavier is a Mineral Wool panel compared to PIR?

Mineral wool panels are significantly heavier. A 100mm Mineral Wool panel is often double the weight of a 100mm PIR panel due to the high density of the stone wool fiber.

4. Why is the "Skin Material" usually Steel?

Galvanized steel is the industry standard for structural rigidity. Aluminum is lighter but more expensive and less rigid. Stainless steel is used for hygiene but is heavy and costly.

5. Does the panel profile (ribbing) affect weight?

Yes. A roof panel with high ribs uses more steel than a flat wall panel to cover the same width. For roofing panels, add 10-15% to the calculated skin weight for safety.

6. Can I calculate roof panel weight with this tool?

Yes, but consider the "developed width" of the steel. For accurate roof panel weight, you might slightly overestimate the skin thickness or use the "flat" equivalent.

7. What is the max weight for manual handling?

Health and safety regulations often suggest a max of 25kg for one person. A single 6m PIR panel can weigh 70kg+, requiring mechanical lifting (vacuum lifters or cranes).

8. How accurate is this calculator for logistics?

It is accurate within roughly 5%. Always allow a safety margin for pallets, packaging film, and protective wooden blocks when calculating truck loads.