From RIMA ( Reflective Insulation Manufacturers Association ) ( Handbook #3 )
Complete document available for download here.   Source RIMA - Handbook3.doc 

INTERIOR RADIATION CONTROL COATINGS (IRCC)

Definition of an IRCC
 

An Interior Radiation Control Coating is a non-thickness dependent, low emittance coating.  When applied to non-porous building materials such as plywood, OSB, metal siding or plasterboard, it lowers the normal surface emittance of these materials to 0.24 or lower and may be effectively used as an interior radiant barrier.

Physics of an IRCC

An IRCC works by changing the emittance of the surface where it is applied.  Building products, such as wood, brick, painted surfaces and plasterboard exhibit high emissivities (0.7 - 0.95).  When heated above the temperature of adjacent surfaces, they radiate most of their heat energy to cooler surfaces.  An IRCC works by lowering their surface emittance to 0.24 or lower, lessening their ability to radiate heat.

Definition of an Interior Radiation Control System (IRCCS)

A building construction consisting of a low emittance (normally 0.25 or less) surface bounded by an open air space.  An IRCCS is used for the sole purpose of limiting heat transfer by radiation and is not specifically intended to reduce heat transfer by convection or conduction.  (ASTM C 1321, section 3.2.3)

Thus, an IRCCS is similar to a Radiant Barrier System (RBS) but is somewhat less efficient due to its higher emissivity and is comprised of a coating on a building surface, not a foil or film product.

Advantages of an IRCC

An IRCC is normally applied using airless spray equipment, resulting in very low labor costs and greatly reduced installation times.  Also, a water based IRCC can be safely installed in existing structures where the costs of installing foil or film products may be prohibitive or impractical.  An IRCC may also be used in many manufactured products (such as infrared heat reflectors of automotive parts) where it is impractical to adhere foil or film radiant barriers.

Installation methods for an IRCC

Since an IRCC is a paint product, spray painting, either air atomization or airless is the most effective method of installation.  Where spray painting is not practical.  An IRCC may be applied using a low nap roller.  Brush painting is usually impractical since these coatings are very low viscosity and not formulated for brush application.

The IRCC may be applied to a building surface already in place (such as the underside of an installed roof deck or the inside of a wall) or it may be applied to a building component before it is installed (such as roof decking painted while laying on the ground before it is lifted into place.  Regardless when a building component is painted with and IRCC, it is imperative that after installation the surface painted with the IRCC face a minimum of a 2” air space.

Typical installations of an IRCC

Under Roof

Interior Side Walls

Exterior Side Walls

Other Possible Uses - Construction

An IRCC is a paint product therefore it can be used on almost any solid surface where paint can be applied and where radiant heat transfer is a problem.  An example would be painting the inside of a boiler room to retain heat that might make adjacent areas uncomfortable.  Even painting the boiler, itself, might make it operate more efficiently.  Freestanding heat shield in welding bays or at foundries can be painted with an IRCC.  Exterior roof surfaces may also be painted with an IRCC to repel summer heat and lower radiation losses in the winter.

Other Possible Uses of an IRCC

IRCC technology has many applications in manufacturing and industry.  It is used in the automotive industry to keep temperature sensitive parts and automotive interiors cool.  It is used in the lighting industry to make plastic reflectors for heat lamps and radiant heating devices.  It is used as a heat reflecting surface in industrial ovens.  It is used on high temperature process piping and storage tanks in chemical plants to lessen heat loss.  Any process or device that is temperature sensitive to infrared heat problems or uses reflected heat in its operation may be a candidate for IRCC technology.