Polyurethane Insulation Panel
Polyurethane Insulation Panel

Polyurethane insulation panel, also marked as PUR, is often used as structural insulated panels in construction fields.

The panel is structured by uniform dispersion molding (UDM), achieving a uniform PU injection between panel skins.

Thermal Insulation

The biggest advantage of the polyurethane insulation panel is thermal insulation. The co-efficiency of thermal conductivity is 0.023w/m*k, lower than almost all kinds of other foam materials.

Secondly, the PU insulation panel is impermeable to water and a lot of other liquids. The skins are also laminated into a tongue-and-groove edge profile, easy for connection and installation.

tongue-and-groove edged panel skin
Tongue-and-groove Edged Panel Skin

Flame Resistant Polyurethane Insulation Panel

In addition, TOPOLO is also able to provide a flame-resistant polyurethane insulation panel. The products not only comply with current energy efficiency regulations but also meet European fire resistance standards. The PU insulation panels reach between F and B-s1, d0 in the Euro-class classification. We may have a special discussion about the fireproof property of PU later.

PU VS EPS in Insulation

There is a long-standing debate over whether expanded polystyrene (EPS) or polyurethane (PUR) panel is better for insulation. This is a complex debate that requires knowledge about several different factors.


EPS is a rigid closed-cell plastic foam that is comprised of hollow, spherical beads that are fused together using steam. Since EPS is 98% air, it is chemically inert.

Polyurethane is “… a foam insulation material that contains a low-conductivity gas in its cells.” It is “… formed by reacting a polyol (an alcohol with more than two reactive hydroxyl groups per molecule) with a diisocyanate or a polymeric isocyanate in the presence of suitable catalysts and additives.”



Polyurethane has one of the highest initial (at the time of installation) R-values per inch in the industry; higher than EPS in equivalent thicknesses. However, EPS insulation will maintain its initial R-value long after it is first installed.

Polyurethane uses the thermal resistance of its blowing agent to attain higher initial R-values. However, it loses R-value over time due to thermal drift. According to the Building Science Corporation, thermal drift is, “The loss of R-value over time in foam that contains captive blowing agents. Air enters the cells of the foam, diluting or replacing the lower-conductivity blowing agent…”

According to the US Department of Energy, the most thermal drift of polyurethane occurs during the first two years. Oak Ridge National Laboratory chose to study the effect of thermal drift on “aged” R-value, or long-term thermal resistance, after a five-year period. They found that in as short as 2-5 years, the thermal resistance of EPS and polyurethane insulation panels will be nearly equivalent.



Polyurethane insulation panels are more expensive than EPS foam panels. This cost is due to an initial higher R-value. However, as the Oak Ridge National Laboratory study shows, this R-value degrades over time due to thermal drift. And, at the end of five years, the long-term thermal resistance is similar.



TOPOLO polyurethane insulation panels have been independently tested and received a one-hour fire-resistance rating. Although EPS insulation is considered combustible, this does not mean that it will burst into flame. It simply means that it behaves similarly to other materials such as wood or paper. Fire codes usually require a fire barrier on the interior face of any wall (no matter the insulation type), which is easily met by using gypsum wallboard.

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