Sandwich panels – what should you know?

Sandwich panels – what should you know?

What is a sandwich panel?

A sandwich panel is a product used to walls and roofs of buildings. Each panel comprises a core of thermoinsulating material, skinned on both sides with sheet metal. Sandwich panels are not structural materials but curtain materials. The structural forces are carried by the steel framework or other carrier frame to which the sandwich panels are attached.

The types of sandwich panel are generally grouped by the thermoinsulating material used as the core. Sandwich panels with cores of EPS (expanded polystyrene), mineral wool and polyurethane (PIR, or polyisocyanurate) are all readily available.

The materials mainly vary in their thermal insulating performance, sound insulating performance, reaction to fire and weight.

Why use sandwich panels anyway?

Sandwich panels are widely acclaimed due to a number of benefits, mainly those related to cost. Comparisons between frame or stud partition technology (frames lined with sandwich panels) and traditional building technologies based on masonry walls reveal advantages of sandwich panels in three key areas:

1. Direct costs

Construction of a building in either technology requires similar capital expenditure levels. 
The comparison in this area includes the costs of construction materials, labour and shipping.

2. Construction time

A building based on a traditional masonry process may take 6 to 7 months to complete. 
A building of the same volume utilising stud partitions takes just 1 month to complete.
The construction time is business-critical. The sooner a production building or warehouse is commissioned for use, the sooner a return on the investment can be achieved.

Stud partition buildings are assembled rather than “built”. The finished structural parts and cladding components arrive on site, and are then assembled like a house of toy bricks. Another plus is that there is no need to wait for the building shell to lose excess moisture.

3. Construction processes

In some sectors of industry, the construction requirements can be critical for a building project. Stud partition construction is a ‘dry process’, with no water needed for the construction materials. A dry process requires only the assembly of the structure and fixing of the cladding (here, the sandwich panels) with screws.

Traditional masonry construction uses ‘wet processes’, which require significant amounts of water to make the mortar for bricklaying, concrete for casting or the plaster for rendering.

Some sectors of industry, like wood processing or pharmaceutical manufacture, require fixed and controlled relative humidity levels, which preclude wet construction processes.