1. LTHW Heating, Condenser Cooling Water, Dry Cooler Circuits (up to 85°C)
| THICKNESS BASED ON BS5422 TABLES 12 & 13 | |
| NOMINAL PIPE SIZE (mm) | MINERAL WOOL THICKNESS (mm) |
| 15 | 25 |
| 20 | 25 |
| 25 | 25 |
| 32 | 30 |
| 40 | 30 |
| 50 | 30 |
| 65 | 30 |
| 80 | 30 |
| 100 | 30 |
| 125 | 40 |
| 150 | 40 |
| 200 | 40 |
| 250 | 40 |
| 300 and above | 40 |
| flat surfaces | 40 |
2. Domestic Hot Water Services
| THICKNESS BASED ON BS5422 TABLES 15 | |
| NOMINAL PIPE SIZE (mm) | MINERAL WOOL THICKNESS (mm) |
| 15 | 25 |
| 20 | 30 |
| 25 | 30 |
| 32 | 30 |
| 40 | 30 |
| 50 | 30 |
| 65 | 40 |
| 80 | 40 |
| 100 | 40 |
| 125 | 40 |
| 150 | 40 |
| flat surfaces | 50 |
3. Internal Cold Water Services, Chilled Water Services and Fire Protection Services - Protection from Freezing, Including Cold Water Feeds and Vents
| THICKNESS BASED ON BS5422 TABLES 12 & 13 | |
| NOMINAL PIPE SIZE (mm) | MINERAL WOOL THICKNESS (mm) INDOORS (1 & 2) |
| 15 | 60 |
| 20 | 50 |
| 25 | 30 |
| 32 | 30 |
| 40 | 30 |
| 50 | 30 |
| 65 | 30 |
| 80 | 30 |
| 100 | 25 |
| 125 | 25 |
| 150 | 25 |
| 200 | 25 |
| 250 | 25 |
| 300 and above | 25 |
| flat surfaces | 25 |
• Indoor installations include roof spaces, ventilated ground floor voids and unheated basements etc.;
• Also includes hot services that operate intermittently located in spaces in (1) above.
The above thicknesses comply with or exceed the requirements of Byelaw 49 of the Water Supply Byelaws ad BS 6700 1987.
4. Internal Cold Water Services, Chilled Water Services and Rainwater Pipes to Prevent Condensation
| THICKNESS BASED ON BS 5422 TABLE 7 | |||
| NOMINAL PIPE | MINERAL WOOL THICKNESS (mm) | ||
| SIZE (mm) | 10OC* | 5OC* | 0OC* |
| 15 | 20 | 25 | 30 |
| 20 | 20 | 25 | 30 |
| 25 | 20 | 30 | 40 |
| 32 | 20 | 30 | 40 |
| 40 | 20 | 30 | 40 |
| 50 | 25 | 30 | 40 |
| 65 | 25 | 30 | 40 |
| 80 | 25 | 30 | 40 |
| 100 | 30 | 40 | 50 |
| 125 | 30 | 40 | 50 |
| 150 | 30 | 50 | 60 |
| 200 | 30 | 50 | 60 |
| 250 | 40 | 50 | 60 |
| 300 | 40 | 50 | 60 |
| flat surfaces | 40 | 60 | 80 |
* Temperature and contents
10ºC – Cold water services
5ºC – Chilled water services
0ºC – Rainwater pipes
Cold water storage tanks, including feed and expansion tanks.
• All flat sided tanks – 50mm thick;
• All externally flanged tanks – 80mm thick applied in two layers, each 40mm thick.
5. Ductwork Carrying Warm Air
| THICKNESS BASED ON BS 5422 TABLE 16 | |
| TEMPERATURE DIFFERENCE BETWEEN AIR IN DUCT AND AMBIENT STILL AIR | MINERAL WOOL THICKNESS (mm) |
| +10K | 40 |
| +25K | 50 |
| +20K | 60 |
6. Ductwork Carrying Chilled Air (Condensation Control)
| THICKNESS BASED ON BS 5422 TABLE 17 | |
| MINIMUM AIR TEMPERATURE INSIDE DUCT | MINERAL WOOL THICKNESS (mm) |
| 150C – 200C | 25 |
| 100C – 140C | 40 |
| 50C – 90C | 60 |
| 00C – 40C | 70 |
7. Refrigeration Pipework for Condensation Control
| APPLICATION | REFRIGERANT PIPE O/D | ARMAFLEX INSULATION THICKNESS (mm) THICKNESS BASED ON BS 5422 TABLE 2 FO | ||
| NORMAL CONDITIONS. | ||||
| MILD CONDITIONS AMBIENT 20ºC R.H 60% | NORMAL CONDITIONS AMBIENT 20ºC R.H 70%* | SERVE CONDITIONS AMBIENT 25ºC R.H 80% | ||
| Down to minus 18ºC | 15 to 114mm | 19 | 19 | 32 |
| Above 114mm and other flat sheet applications 19 | 19 | 25 | 45 | |
| Down to -30oC | 15 to 114mm | 19 | 32 | 38 |
| Above 114mm and other flat sheet applications 19 | 19 | 32 | 64 | |
| Down to -40oC | 15 to 114mm | 25 | 32 | 49 |
| Above 114mm and other flat sheet applications 25 | 32 | 41 | 73 | |
* Unless otherwise indicated, normal conditions are to be applied.
• Liquid refrigeration pipes external to buildings and subject to solar radiation shall have a reflective or light coloured finish applied to the “Armaflex” insulation.
