To avoid heat loss and reduced efficiency pipe work in heating systems should always be insulated. Very hot systems, like hot water and steam systems should also be insulated to avoid potential personal injuries.
The table below indicates recommended insulation thickness.
* based on insulation with thermal resistivity in the range 4 - 4.6 ft2 hr oF/ Btu in
The table below indicates recommended insulation thickness.
| Recommended minimum Thickness of Insulation (inches)* | ||||
| Nominal Pipe Size NPS (inches) | Temperature Range (oC) | |||
| 50 - 90 | 90 - 120 | 120 - 150 | 150 - 230 | |
| Temperature Range (oF) | ||||
| 120 - 200 | 201 - 250 | 251 - 305 | 306 - 450 | |
| Hot Water | Low Pressure Steam | Medium Pressure Steam | High Pressure Steam | |
| < 1" | 1.0 | 1.5 | 2.0 | 2.5 |
| 1 1/4" - 2" | 1.0 | 1.5 | 2.5 | 2.5 |
| 2 1/2" - 4" | 1.5 | 2.0 | 2.5 | 3.0 |
| 5" - 6" | 1.5 | 2.0 | 3.0 | 3.5 |
| > 8" | 1.5 | 2.0 | 3.0 | 3.5 |