Pipe lagging (AC pipe insulation)

Pipe lagging is the foam insulation wrapped around the cold pipework of an AC or chilled-water system, the refrigerant lines from a split, or the chilled-water pipes feeding an FCU. It does two things: it stops the cold pipe surface condensing the humid air around it (which is what causes the sweating, dripping and ceiling stains people report), and it stops the system losing its cooling into the ceiling void before it reaches the room, wasting energy. In the UAE lagging matters more than almost anywhere because the humidity and heat punish any bare cold surface. The catch is that lagging perishes — it goes hard, cracks, or gets crushed and gapped over years — and once it fails the pipe sweats and the efficiency drops, which is exactly why AC pipe insulation is a real maintenance item, not a fit-and-forget one. Re-lagging perished sections is a cheap fix that stops both the drips and the waste.