Exhaust Ducts and Stacks

Chimney and exhaust duct insulation

Isover U Tech Range


Thermal insulation is key to reducing heat loss and protecting personnel working on the plant. Even more important is the control of flue gas temperature to prevent condensation of, for instance, sulphuric acid, which will lead to corrosion and reduction in the service life and/or functionality of the whole system.
 

Industrial chimneys and exhausts - ISOVER solutions for circular and rectangular structures

For rectangular ducts, the ISOVER range includes ULTIMATE U Tech slabs and stone wool slabs, which offer different levels of thermal performance and maximum operating temperature. These products not only provide excellent thermal insulation performance, but have the flexibility and mechanical strength needed to fit perfectly within the available space or insulated metal duct constructions requiring fire resistance of up to 120 minutes. 

High fluctuating temperatures and vibrations in chimneys and exhaust systems place additional demands on the insulation, requiring products that are both flexible and offer high mechanical strength. ISOVER's ULTIMATE U Tech and stone wool wired mats provide the perfect solution, offering a range of different performance and temperature levels for flexible and circular or uneven structures.

High flow speeds, pressures and turbulence in the media are a prime cause of noise within the system, requiring efficient acoustic insulation, especially in inhabited urban areas. When integrated into the construction, ISOVER mineral wool insulation will not only provide thermal performance and fire protection, it will also offer effective acoustic insulation to significantly reduce noise emissions from the system.
 

Industrial chimneys - ISOVER flexible and safe solutions

 
ISOVER insulation for chimneys

Thermal insulation of industrial chimneys is particularly important to prevent corrosion of the internal steel channels.

With ISOVER U Tech and stone wool wired mats, the insulation of circular structures is flexible, fast and efficient. With ULTIMATE insulation space savings of up to 25% can be achieved, especially in higher temperature systems, which can be critical in environments where space is typically limited. All ISOVER Wired Mats are available with reinforced aluminium facing to limit dust, provide an effective vapour barrier, and make removal and re-use of the insulation system easier and more efficient.

At lower temperatures, up to 250°C, glass wool or stone wool lamella mats provide an alternative to wired mats.
  • For smaller diameter chimney pipes, ISOVER offers a specially designed range of stone wool pipe sections, as well as ULTIMATE pipe sections for higher temperature use. These high performance sections are preformed to exact dimensions to provide a quick and efficient method of insulation.
  • For a wider range of chimney pipe diameters, ISOVER can supply special slabs with multi-plate strips to suit individual customer requirements. Ideal for prefabricated chimneys, these products allow high levels of insulation to be achieved quickly, with a perfect fit and without the compromises in thermal insulation efficiency which can be associated with lamella or wired mats.

ISOVER slabs are available with different facings, including comfort tissue for dust-free conditions or to improve acoustic behaviour, and reinforced aluminium which acts as a vapour barrier to reduce the risk of corrosion under insulation (CUI).
 

Flue gas and hot air ducts - ISOVER solutions combining thermal efficiency and safety

 
ISOVER insulation for chimneys hot air ducts
 

Choosing the right insulation system for flue gas and hot air ducts in power or processing plants depends on factors like temperature, shape, size and the mechanical performance needed. With the complete range of ULTIMATE, glass wool and stone wool products, specially designed for this application, ISOVER will always offer the perfect solution to meet your specification needs.

For lower temperature circular ducts, ISOVER offers glass wool ductwrap or light rolled mats, whilst with ULTIMATE U Tech rolls 2.0 and ULTIMATE U Tech rolls 4.0, operational temperature increases up to 460°C MST (580°C at 250 Pa). ISOVER U Tech and stone wool wired mats complete the range of flexible solutions, with operational temperatures up to 660°C. Where additional mechnical strength is required, ISOVER lamella mats provide the answer.

In the case of rectangular ducts, slab solutions are generally easier and faster to install, especially where multilayer applications are involved. At lower temperatures, up to 250°C, ISOVER glass wool slabs provide a light and economic solution. At constantly higher or intermittent temperatures, however, ULTIMATE U Tech slabs offer a higher level of security and optimum energy efficiency at a significantly lower weight than traditional stone wool solutions.


For applications requiring high mechanical compression strength to carry heavier loads, ISOVER stone wool slabs are available in various performance levels. All ISOVER slabs can be easily fixed with normal pins and washers, although local specifications and standards should be followed during construction.

Special hydrophobic and AS-quality ISOVER slabs provide additional protection from corrosion, extending the life and efficiency of systems with higher corrosion risk.

Product range

Project references - Sharing industrial insulation expertise

For more than 30 years, we’ve been providing insulation for key industry players. Find the perfect reference to inspire your project and see how our products can meet your needs. With a reputation for quality products and total commitment to customer satisfaction, ISOVER constantly works to improve not only the thermal performance of its insulation products but also the resources necessary to manufacture them.