Quick answer
Aluminium cladding or PIB — how do you choose an external finish?
Aluminium cladding is a rigid metal jacket giving strong mechanical protection and a clean appearance, suited to roof runs and visible plant. PIB (polyisobutylene) is a flexible weatherproof membrane that follows irregular shapes and suits tight plant rooms. Both protect external insulation from weather; the choice follows protection needs, access and appearance.
What is aluminium cladding?
Aluminium cladding is a thin metal jacket fitted over external insulation, usually on pipework or ductwork running outside or through plant rooms. It gives mechanical protection against impact, a smart finished appearance and a durable weather barrier. Joints are sealed and riveted or banded to stay weathertight.
What is PIB?
PIB, or polyisobutylene, is a flexible weatherproof membrane applied over insulation. Because it is flexible, it follows valves, bends and irregular fittings that a rigid metal jacket cannot easily cover. It is bonded and sealed to form a continuous barrier against rain and moisture ingress.
Where does each suit?
Aluminium cladding suits exposed roof runs, risers and visible plant where mechanical damage is a risk and a clean finish is wanted. PIB suits congested plant rooms with many fittings, where the flexibility to jacket valves and awkward shapes matters more than a rigid surface.
How do they protect external insulation?
Both finishes keep water off the insulation. Wet mineral wool loses its thermal performance, and freeze-thaw cycles break it down. A continuous, sealed weatherproof layer keeps the insulation dry so it holds its specified thickness and performance for the life of the system.
Can they be combined?
Yes. A common approach is aluminium cladding on straight external runs for durability and appearance, with PIB over valves and irregular fittings where metalwork is impractical. The two are detailed together at the junctions so the weatherproof barrier stays continuous.
Need this on your project?
Send your drawings or specification and we will return a written quotation.
Contact us