Piping - Recommended Insulation Thickness
To avoid heat loss and reduced system 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.
| Nominal Pipe Size NPS (inches) | Insulation Thickness (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 |
* based on insulation with thermal resistivity in the range 4 - 4.6 ft2 hr oF/ Btu in (typical for mineral wool at room temperature)
- 1 inch = 25.4 mm
Related Topics
• Heat Loss and Insulation
Heat loss from pipes, tubes and tanks - with and without insulation. Use of materials lke foam, fiberglass, rockwool and more.
• Insulation
Calculate heat transfer and heat loss from buildings and technical applications. Heat transfer coefficients and insulation methods available for reduction of energy consumption.
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