Insulation is a consumable. Once it ages, performance drops sharply and energy is wasted; once the facing starts to fail, the pipe underneath begins to corrode. The most dangerous assumption is that because something is still attached, it must be fine. Here is what to expect by material, and how to judge when replacement is due.
Expected service life by material
| Glasswool (indoor) | 10–20 years — long service is possible while the facing is intact |
| Glasswool (outdoor exposed) | 5–10 years — the facing degrades quickly under UV and rain |
| Mineral wool | 15–25 years — high heat resistance gives long life even in hot service |
| PIR urethane pipe insulation | 10–15 years — shrinks and hardens under repeated hot exposure |
| Rubber foam | 7–12 years — weak against UV and ozone, degrading quickly outdoors |
| Cerakwool blanket | 10–20 years depending on the plant — check for shrinkage and dusting |
| Insulation jackets | 3–7 years — depending on skin material and environment |
Seven signs that replacement is due
- The facing (ALGC or aluminum casing) is dented, lifting or has come away
- Condensation or water marks are visible on the insulation surface
- The insulation collapses or crumbles when pressed (glasswool, mineral wool)
- Urethane insulation has hardened, shrunk or cracked
- The surface of rubber foam is cracking and crumbling
- The pipe surface is noticeably hotter than it used to be — a sign of increased heat loss
- Cerakwool is dusting heavily, indicating shrinkage and devitrification
What happens if it is left
| Increased energy loss | Aged insulation performs 30–60% worse than new — a sharp rise in steam and heat loss cost |
| Accelerated pipe corrosion | Damaged facing → moisture ingress → external pipe corrosion → shortened pipe life |
| Fire risk | Insulation falling away from hot pipework risks contact with nearby combustibles |
| Burn risk to personnel | Exposed hot pipework causes contact burns |
| Unstable process temperature | Uneven insulation → fluctuating process temperature → reduced product quality |
Using a thermal imaging camera
An infrared camera identifies insulation defects that are invisible to the eye. Well-insulated pipework shows a uniformly low surface temperature, while defective sections show up hot. Running a thermal survey alongside scheduled preventive maintenance lets you predict replacement timing accurately.
⚠️If the facing is damaged, repair or replace it immediately. Leaving it leads to moisture uptake and corrosion inside, and the cost of full replacement is far higher. For inspection and replacement quotations: +82 10-4266-9745
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