{"product_id":"k-flex-st-tube-25mm","title":"K-Flex ST Tube Pipe Insulation 25mm Wall","description":"\u003cp\u003e\u003cstrong\u003eK-Flex ST Tube 25mm Wall\u003c\/strong\u003e is a flexible closed-cell elastomeric foam pipe insulation — also known as AC pipe lagging, refrigerant pipe insulation, or HVAC pipe wrap — manufactured by K-Flex in Italy to EN 14304 standards. The 25mm wall thickness is suited to commercial and high-specification HVAC applications where enhanced thermal resistance is required.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eKey Specifications:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWall thickness: 25mm\u003c\/li\u003e\n\u003cli\u003eMaterial: Closed-cell elastomeric foam (NBR\/PVC)\u003c\/li\u003e\n\u003cli\u003eThermal conductivity (λ): ≤ 0.040 W\/(m·K) at 0°C\u003c\/li\u003e\n\u003cli\u003eOperating temperature: -50°C to +105°C\u003c\/li\u003e\n\u003cli\u003eFire rating: Class 1 (BS 476 Part 7)\u003c\/li\u003e\n\u003cli\u003eStandard: EN 14304\u003c\/li\u003e\n\u003cli\u003eColour: Black\u003c\/li\u003e\n\u003cli\u003eCountry of origin: Italy\u003c\/li\u003e\n\u003cli\u003eSold per metre length\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eAvailable bore sizes:\u003c\/strong\u003e 12mm, 15mm, 18mm, 22mm, 28mm, 35mm, 42mm, 48mm, 54mm, 60mm, 67mm, 76mm, 89mm, 92mm, 108mm, 114mm, 133mm, 140mm, 160mm, 170mm\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompatible Systems:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eCommercial VRF\/VRV refrigerant pipework\u003c\/li\u003e\n\u003cli\u003eLarge-bore chilled water distribution pipework\u003c\/li\u003e\n\u003cli\u003eIndustrial refrigeration pipework\u003c\/li\u003e\n\u003cli\u003eHigh-specification HVAC installations requiring enhanced thermal performance\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCompatible Brands:\u003c\/strong\u003e Suitable for use on Daikin, Mitsubishi Electric, Fujitsu, Panasonic, Samsung, LG, and all other VRF\/VRV and commercial AC systems using copper ACR pipework.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhen to Use 25mm Wall Insulation:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eUse where enhanced thermal resistance is required beyond standard 13mm or 19mm wall — typically commercial VRF systems, large chilled water distribution, or industrial refrigeration.\u003c\/li\u003e\n\u003cli\u003ePrevents condensation on suction lines and heat gain on liquid lines in high-ambient or long pipe run installations.\u003c\/li\u003e\n\u003cli\u003eThe built-in vapour barrier eliminates the need for additional vapour barrier tape on most applications.\u003c\/li\u003e\n\u003cli\u003eUV-resistant surface suitable for short exposed sections, though aluminium cladding is recommended for long-term external exposure.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eChoosing the Right Wall Thickness:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-9mm-wall\"\u003e9mm\u003c\/a\u003e — tight spaces, short runs, domestic AC\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-13mm-wall\"\u003e13mm\u003c\/a\u003e — standard AC and HVAC (most common)\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-19mm-wall\"\u003e19mm\u003c\/a\u003e — refrigeration and low-temperature systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e25mm\u003c\/strong\u003e — commercial and high-specification applications\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-32mm-wall\"\u003e32mm\u003c\/a\u003e | \u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-40mm-wall\"\u003e40mm\u003c\/a\u003e | \u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-50mm-wall\"\u003e50mm\u003c\/a\u003e — industrial and heavy-duty applications\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eST vs PE — Which Insulation Do You Need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eK-Flex ST (this product)\u003c\/strong\u003e — closed-cell elastomeric rubber (NBR\/PVC). Superior vapour barrier, flexible, Class 1 fire rated. Preferred for refrigeration, AC, and chilled water where condensation control is critical.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/k-flex-pe-polyethylene-pipe-insulation\"\u003e\u003cstrong\u003eK-Flex PE\u003c\/strong\u003e\u003c\/a\u003e — polyethylene foam. Lighter, lower cost, easier to cut. Suited to domestic heating, plumbing, and lower-specification HVAC, where vapour barrier performance is less critical.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFrequently Bought With:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/k-flex-k-420-contact-adhesive-for-pipe-insulation-250ml\"\u003eK-Flex K-420 Contact Adhesive 250ml\u003c\/a\u003e — recommended adhesive for joining and sealing K-Flex ST insulation to maintain vapour barrier integrity\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/50mm-self-adhesive-aluminium-foil-tape-for-hvac-duct-sealing-uk\"\u003e50mm Self-Adhesive Aluminium Foil Tape\u003c\/a\u003e — for sealing joints and protecting exposed external sections\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/products\/75mm-premium-self-adhesive-aluminium-foil-tape-for-hvac-sealing-uk\"\u003e75mm Premium Aluminium Foil Tape\u003c\/a\u003e — for wider joint coverage on larger bore insulation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFurther Reading:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/blogs\/hvac-tools-guide\/armaflex-vs-k-flex-pipe-insulation\"\u003eArmaflex vs K-Flex Pipe Insulation — Which Is Best for HVAC?\u003c\/a\u003e — a detailed comparison of the two leading elastomeric insulation brands to help you specify with confidence.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFrequently Asked Questions:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdl\u003e\n\u003cdt\u003e\u003cstrong\u003eWhat wall thickness do I need for a VRF\/VRV system?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003e25mm wall is recommended for VRF\/VRV long pipe runs and commercial systems where heat gain and condensation control are critical. For standard domestic split AC, \u003ca href=\"\/products\/k-flex-st-tube-pipe-insulation-13mm-wall\"\u003e13mm wall\u003c\/a\u003e is the most common specification.\u003c\/dd\u003e\n\u003cdt\u003e\u003cstrong\u003eIs K-Flex ST suitable for outdoor use?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003eK-Flex ST has a UV-resistant surface suitable for short exposed sections. For long-term external exposure, protect with aluminium foil tape or cladding. For fully external applications, K-Flex Solar is the recommended grade.\u003c\/dd\u003e\n\u003cdt\u003e\u003cstrong\u003eWhat bore size do I need for 3\/4\" copper ACR pipe?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003e3\/4\" (19mm OD) copper ACR pipe requires 22mm bore insulation. Select the 22mm bore variant from the size selector above.\u003c\/dd\u003e\n\u003cdt\u003e\u003cstrong\u003eIs K-Flex ST Class O rated?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003eK-Flex ST carries Class 1 fire classification to BS 476 Part 7. For Class O (BS 476 Part 6 and 7 combined), specify K-Flex ST Class O grade — contact us for availability.\u003c\/dd\u003e\n\u003cdt\u003e\u003cstrong\u003eCan K-Flex ST be used on chilled water pipework?\u003c\/strong\u003e\u003c\/dt\u003e\n\u003cdd\u003eYes. K-Flex ST is suitable for chilled water systems operating within the stated temperature range. Ensure all joints are fully glued with \u003ca href=\"\/products\/k-flex-k-420-contact-adhesive-for-pipe-insulation-250ml\"\u003eK-420 adhesive\u003c\/a\u003e to maintain vapour barrier integrity.\u003c\/dd\u003e\n\u003c\/dl\u003e","brand":"K-Flex","offers":[{"title":"12mm","offer_id":57273488834937,"sku":"25012005508","price":10.4,"currency_code":"GBP","in_stock":true},{"title":"15mm","offer_id":57273488867705,"sku":"25015005508","price":11.37,"currency_code":"GBP","in_stock":true},{"title":"18mm","offer_id":57273488900473,"sku":"25018005508","price":11.66,"currency_code":"GBP","in_stock":true},{"title":"22mm","offer_id":57273488933241,"sku":"25022005508","price":12.24,"currency_code":"GBP","in_stock":true},{"title":"28mm","offer_id":57273488966009,"sku":"25028005508","price":14.01,"currency_code":"GBP","in_stock":true},{"title":"35mm","offer_id":57273488998777,"sku":"25035005508","price":15.72,"currency_code":"GBP","in_stock":true},{"title":"42mm","offer_id":57273489031545,"sku":"25042005508","price":16.74,"currency_code":"GBP","in_stock":true},{"title":"48mm","offer_id":57273489064313,"sku":"25048005508","price":19.34,"currency_code":"GBP","in_stock":true},{"title":"54mm","offer_id":57273489097081,"sku":"25054005508","price":19.79,"currency_code":"GBP","in_stock":true},{"title":"60mm","offer_id":57273489129849,"sku":"25060005508","price":21.21,"currency_code":"GBP","in_stock":true},{"title":"67mm","offer_id":57273489162617,"sku":"25067005508","price":25.68,"currency_code":"GBP","in_stock":true},{"title":"76mm","offer_id":57273489195385,"sku":"25076005508","price":27.73,"currency_code":"GBP","in_stock":true},{"title":"89mm","offer_id":57273489228153,"sku":"25089005508","price":30.61,"currency_code":"GBP","in_stock":true},{"title":"92mm","offer_id":57273489260921,"sku":"25092005508","price":33.06,"currency_code":"GBP","in_stock":true},{"title":"108mm","offer_id":57273489293689,"sku":"25108005508","price":35.83,"currency_code":"GBP","in_stock":true},{"title":"114mm","offer_id":57273489326457,"sku":"25114005508","price":37.11,"currency_code":"GBP","in_stock":true},{"title":"133mm","offer_id":57273489359225,"sku":"25133005508","price":39.12,"currency_code":"GBP","in_stock":true},{"title":"140mm","offer_id":57273489391993,"sku":"25140005508","price":42.09,"currency_code":"GBP","in_stock":true},{"title":"160mm","offer_id":57273489424761,"sku":"25160005508","price":48.1,"currency_code":"GBP","in_stock":true},{"title":"170mm","offer_id":57273489457529,"sku":"25170005508","price":52.07,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/0158\/3481\/files\/K-FLEX-ST-Elastomeric-Tube-Ryan-Air-Conditioning-Spares-68794081935735_26a061d3-6a02-47b9-ad35-2732ec2b6d5c.jpg?v=1778759141","url":"https:\/\/www.airconspares.com\/products\/k-flex-st-tube-25mm","provider":"Airconspares.com","version":"1.0","type":"link"}