K-Flex ST Tube Pipe Insulation 13mm Wall

K-Flex ST is a flexible closed-cell elastomeric foam tube designed for thermal insulation of refrigeration, air conditioning, chilled water, and plumbing pipework. Manufactured by K-Flex in Italy to EN 14304 standards.

The 13mm wall thickness is the most widely specified for standard split system AC and domestic HVAC installations. It meets the thermal performance requirements for refrigerant pipework on most residential and light commercial jobs, and is the default choice for HVAC engineers across the UK.

Where This Is Used

• Refrigerant pipework on split system AC installations
• Chilled water and cooling pipework
• Domestic and light commercial HVAC systems
• Plumbing and heating pipework

Choosing the Right Wall Thickness

• 9mm — tight spaces, short runs, domestic AC
• 13mm — standard AC and HVAC (most common)
• 19mm — refrigeration and low-temperature systems
• 25mm — commercial and high-specification applications
• 32mm | 40mm | 50mm — industrial and heavy-duty applications

Key Properties

• Closed-cell NBR/PVC foam — low thermal conductivity (λ ≤ 0.040 W/mK at 0°C)
• Built-in vapour barrier — no additional vapour barrier required
• Self-extinguishing — Class 1 fire rated (BS 476 Part 7)
• Operating temperature range: -50°C to +105°C
• Flexible and easy to fit
• UV resistant surface for exposed installations

Technical Specifications

Sold per metre length. UK stock — available for same day dispatch.