ArmaFlex® UT
ArmaFlex UT is a black, EPDM-based, flexible closed-cell elastomeric insulation available in tubular pipe form and roll form, engineered for upper-temperature mechanical insulation service up to 300°F continuous (350°F intermittent). It maintains a full service temperature range of -297°F to 350°F (intermittent) per ASTM C534, provides low water vapor permeability (0.08 Perm-in) to guard against condensation and mold growth, and carries a 25/50 flame spread/smoke developed rating. The material is low-VOC, non-halogen, and PVC-free.
Key Properties
- Thermal Conductivity (k-value): λd ≤ 0.040 W/(m·K) [k ≤ 0.28 Btu·in/(h·ft²·°F)] at 75°F (24°C) mean temperature, per ASTM C518, ASTM C177
- Water Vapor Permeability: 0.08 Perm-in (1.16 × 10⁻¹³ kg/s·m·Pa), per ASTM E96, Procedure A
- Service Temperature Range: -297°F to 300°F (continuous, full range), 350°F max (intermittent, 30 min per 24-hr operating period), per ASTM C534
- Fire Performance: Flame Spread Index < 25, Smoke Developed Index < 50 (25/50 rated), per ASTM E84 and UL 723
- Density: 3 to 6 lb/ft³ (48 to 96 kg/m³), per ASTM D1667
- Water Absorption: 0.2%, per ASTM C1763, Procedure B
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- Specifications
- Applications
- General Info
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Physical Properties
| Property | Value | Test Method |
| Density | 3 to 6 lb/ft³ (48 to 96 kg/m³) | ASTM D1667 |
Thermal Properties
| Property | Value | Test Method |
| Service Temperature — Full Range, Min. | -183°C (-297°F) | ASTM C534 |
| Service Temperature — Full Range, Max. (Continuous) | 150°C (300°F) | ASTM C534 |
| Service Temperature — Full Range, Max. (Intermittent, 30 min per 24-hr period) | 175°C (350°F) | ASTM C534 |
| Maximum Temperature — Self-Adhering / Lap Seal Products | 180°F (82°C) | — |
| Thermal Conductivity (λd) at 75°F (24°C) Mean Temp | ≤ 0.040 W/(m·K) [≤ 0.28 Btu·in/(h·ft²·°F)] | ASTM C518, ASTM C177 |
| Thermal Conductivity (λd) at 100°F (38°C) Mean Temp | ≤ 0.0415 W/(m·K) [≤ 0.288 Btu·in/(h·ft²·°F)] | ASTM C518, ASTM C177 |
| Thermal Conductivity (λd) at 125°F (52°C) Mean Temp | ≤ 0.0424 W/(m·K) [≤ 0.294 Btu·in/(h·ft²·°F)] | ASTM C518, ASTM C177 |
| Thermal Conductivity (λd) at 150°F (66°C) Mean Temp | ≤ 0.0431 W/(m·K) [≤ 0.299 Btu·in/(h·ft²·°F)] | ASTM C518, ASTM C177 |
| Thermal Conductivity (λd) at 200°F (93°C) Mean Temp | ≤ 0.0447 W/(m·K) [≤ 0.310 Btu·in/(h·ft²·°F)] | ASTM C518, ASTM C177 |
Flame & Fire Performance
| Property | Value | Test Method |
| Surface Spread of Flame | Flame Spread Index < 25; Smoke Developed Index < 50 (25/50 rated) | ASTM E84 and UL 723 |
| UL94 5VA | Pass at minimum thickness 7.5 mm | UL 94 (File No. E535094) |
| UL94 V-0 | Pass at minimum thickness 13 mm | UL 94 (File No. E535094) |
| UL94 V-1 | Pass at minimum thickness 7.5 mm | UL 94 (File No. E535094) |
| Practical Fire Behavior | Self-extinguishing, does not drip, does not spread flames | UL 94 |
Environmental Performance
| Property | Value | Test Method |
| Water Vapor Permeability | 0.08 Perm-in (1.16 × 10⁻¹³ kg/s·m·Pa) | ASTM E96, Procedure A |
| Water Absorption | 0.2% | ASTM C1763, Procedure B |
| UV Resistance | Good | — |
| Resistance to Ozone | Good | ASTM D1149 |
| Mold Growth | Pass | ASTM G21, ASTM C1338 |
| Outdoor Use | Painting with WB finish or weather-resistant protective jacketing required to prevent insulation damage in exterior applications and to comply with IECC/ASHRAE 90.1 insulation protection sections | — |
Compliance
- ASTM E84, UL723 — Compliant
- Manufactured without CFCs, HFCs, HCFCs, PBDEs, or Formaldehyde — Compliant
- Conforms to International Residential Code (IRC) — Compliant
- GREENGUARD Gold Certified — Compliant
- ISO 9001 — Compliant (Armacell North America’s quality management systems certified by Intertek)
- Conforms to International Energy Conservation Code (IECC) — Compliant
- Meets Living Building Challenge and Compliant to Red List — Compliant
- Conforms to ASHRAE 90.1 energy standards — Compliant
- Title 24 California Building Energy Efficiency Standards — Compliant
- Conforms to International Mechanical Code (IMC) — Compliant
- UL 94 — Compliant (File No. E535094)
- Variable Refrigerant Flow (VRF) system piping insulation
- Solar collector piping and equipment insulation
- Refrigeration line insulation
- Hot gas and dual-temperature piping insulation
- Low-pressure steam and stainless steel piping insulation
Common industries: HVAC/R, refrigeration, solar thermal, mechanical insulation contracting, and industrial process piping.
ArmaFlex UT is a black, EPDM-based, flexible closed-cell elastomeric thermal insulation supplied in tubular pipe form — with or without factory-applied lap seal closure — and in roll form (formerly branded as UT SolaFlex). It is designed for upper-temperature mechanical insulation applications, including Variable Refrigerant Flow (VRF) systems, solar collectors, refrigeration, hot gas lines, dual-temperature systems, low-pressure steam, and stainless steel piping, where protection against condensation, mold growth, and energy loss is required at service temperatures up to 300°F continuous (350°F intermittent).
The closed-cell structure provides good resistance to UV radiation and ozone, and the material passes mold growth testing per ASTM G21 and ASTM C1338. For outdoor installations, painting with a water-based finish or application of a weather-resistant protective jacket is required to prevent insulation damage and to satisfy the insulation protection provisions of the International Energy Conservation Code (IECC) and ASHRAE 90.1. ArmaFlex UT is manufactured without CFCs, HFCs, HCFCs, PBDEs, or formaldehyde, and is low-VOC, non-halogen, and PVC-free.
ArmaFlex UT achieves a 25/50 flame spread/smoke developed rating per ASTM E84 and UL 723, and passes UL 94 5VA, V-0, and V-1 flammability testing at specified minimum thicknesses (UL File No. E535094). Compliant with ASTM E84, UL 723, UL 94, manufacture without CFCs/HFCs/HCFCs/PBDEs/formaldehyde, International Residential Code (IRC), GREENGUARD Gold Certification, ISO 9001 (Armacell North America’s quality management systems, certified by Intertek), International Energy Conservation Code (IECC), Living Building Challenge Red List compliance, ASHRAE 90.1 energy standards, Title 24 California Building Energy Efficiency Standards, and International Mechanical Code (IMC).
What differentiates ArmaFlex UT from standard closed-cell elastomeric insulation grades?
ArmaFlex UT is engineered for upper-temperature service, remaining serviceable to 300°F continuous (350°F intermittent for 30 minutes per 24-hour period), while retaining low water vapor permeability and a 25/50 fire rating consistent with the broader ArmaFlex closed-cell elastomeric insulation family.
Why does thermal conductivity matter in material selection for ArmaFlex UT?
Thermal conductivity, expressed as the λd value across mean temperatures per ASTM C518 and ASTM C177, directly determines the insulation's ability to prevent condensation and limit energy loss on piping and equipment. ArmaFlex UT maintains a λd ≤ 0.040 W/(m·K) at 75°F (24°C), rising only to ≤ 0.0447 W/(m·K) at 200°F (93°C), providing consistent thermal performance across its upper-temperature service range.
What is the service temperature range for ArmaFlex UT?
-297°F to 300°F continuous (full range), with an intermittent maximum of 350°F for up to 30 minutes per 24-hour operating period, per ASTM C534. Self-adhering and lap seal products are limited to a maximum of 180°F (82°C).
Is ArmaFlex UT suitable for flame-rated, regulated building environments?
Yes. ArmaFlex UT achieves a 25/50 flame spread/smoke developed rating per ASTM E84 and UL 723, passes UL 94 5VA, V-0, and V-1 flammability testing (UL File No. E535094), and conforms to the International Residential Code (IRC), International Energy Conservation Code (IECC), International Mechanical Code (IMC), ASHRAE 90.1 energy standards, and Title 24 California Building Energy Efficiency Standards. It is also GREENGUARD Gold Certified.
How should ArmaFlex UT be specified?
Specify grade (ArmaFlex UT), wall thickness or roll thickness, inside diameter (for tubular pipe insulation) or roll length, lap seal option (with or without factory-applied closure), compliance requirements, and finished format.
