Construction / Insulating Foam

Insulating Foam

Insulation Foam is a closed cell elastomeric material.  It has a much higher R-value* than an open cell elastomeric foam as moisture and air can’t move freely within the cell foam structure.

First developed in the early 1900’s, closed cell elastomeric foam has had a dramatic impact on the insulation industry. The most notable reason for this is its high moisture resistance, which minimizes the threats associated with moisture (such as mold), but it also ensures steady, long-term thermal performance. The demand for elastomeric foam continues to increase due to a more and more awareness of energy savings in commercial and residential buildings, transportation and electrical appliances.

For the specific application requirements, closed cell elastomeric foams can be formulated to be flame retardant, having low smoke emission and reducing noise (vibration damping). 

Factors influencing performance characteristics like, sound deadening,  and smoke suppression and flame retardancy are greatly affected by the selection of the fillers. At Sibelco we have a wide range of fillers so the producer can carefully combine them to obtain the required performance:

  • Flame-retardancy: ATH and Hydromagnesite
  • Smoke suppression: Hydromagnesite
  • Sound deadening : Baryte
  • Mechanical strength: treated ATH
  • Cost effective: all 

Insulation is applied to keep heat away, maintaining a low temperature, from the insulated part (e.g. in a refrigerator) or to keep the heat inside, maintaining a high temperature (e.g.  for piping for central heating systems / hot water plumbing). 

Many examples of insulation can be found in Heating, Ventilation and Air Conditioning (HVAC) applications where pipe insulations are used to slow down temperature increases and control condensation drip from chilled water and refrigeration systems. 


Sheet insulations are applied in situation where large surfaces need to insulated, like in large piping and fittings, tanks, and vessels. Their flexibility allows application to curved and irregular surfaces. They are very adaptable to making all types of fitting cover insulations.

There are many types of insulation foam materials, but the most common used are based on synthetic rubber blend of typically nitrile butadiene rubber (NBR) with Polyvinyl chloride (PVC) or ethylene-propylene-diene monomer (EPDM), fillers, additives and course a chemical foaming agent. 

These components are combined in a large mixer. The mixture is then put through extruding equipment to form a particular profile or shape, typically either a round tube or a flat sheet. The profile is heated in an oven to a specific temperature, a process that causes the chemical foaming agent to change from a solid to a gas. When this occurs, thousands of tiny air pockets (cells)—all of which are connected—form. The profile is carefully cooled to ensure that these cells remain unbroken and intact, maintaining the material’s closed cell structure. It is then cut to size and packaged for shipment. 


* R-Value is a measure of the thermal resistance used in the building and construction industry