PUREX NG OC500 (formerly known as PUREX NG 0810NF) is a two-component semi-rigid open-cell polyurethane spray foam system applied using specialist high-pressure spray equipment. It is the manufacturer’s flagship open-cell product — a system with a long track record across residential insulation projects — and is particularly suited to thermal and acoustic insulation of walls, ceilings, attics, lofts, and floors in single-family housing construction.
The open-cell structure gives the foam excellent sound-absorbing properties, achieving a weighted sound absorption coefficient αw of 0.50 (LH) and a product class D rating per EN ISO 11654, with a sound absorption rating of “absorptive” per VDI 3755/2000. These acoustic properties make it a strong choice for contractors where both thermal and noise reduction performance are required. The declared thermal conductivity is 0.038 W/mK, with a foam core density in the installed product of 7–10 kg/m³ per EN 1602.
The system contains no CFC, HCFC, or HFC blowing agents. Mould resistance has been confirmed by the Building Research Institute (ITB) and the product carries CE marking under EN 14315-1:2013. Because of its open-cell structure, installed foam must not be exposed to prolonged mechanical stress, moisture, steam condensation, or weathering during its service life. A suitable thermal and fire barrier — such as 12mm gypsum plasterboard — must be installed between the foam and the building interior to meet fire control requirements.
Application requires specialist high-pressure spray equipment with a spray head. Component A must be thoroughly mixed before use. Raw material temperature at the head inlet should be 45–65°C, with an ambient application temperature of 5–30°C and a recommended surface temperature of 5–40°C. The system reaches its final mechanical properties within 24 hours of application. For some coated plastic surfaces, surface preparation may be required to achieve adequate coating adhesion.
The product carries CE marking under EN 14315-1:2013, with mould resistance independently confirmed by ITB. When installed behind 12mm gypsum plasterboard, the system achieves a reaction to fire classification of B-s1, d0 per EN 13501-1. Available in Ireland and the UK through Spray Foam Direct Distributions.
| Certification | Reference |
|---|---|
| EN 14315-1:2013 | European harmonised standard for spray-applied rigid/semi-rigid polyurethane foam insulation. CE marking and Declaration of Performance issued per Regulation (EU) No 305/2011 |
| EN 13501-1 | Reaction to fire classification — Class F (unprotected); B-s1, d0 when installed with 12mm gypsum plasterboard lining per EN 13501-1 |
| DIN 4102 | Reaction to fire — Class B3 (unprotected) |
| VDI 3755/2000 | Sound absorption rating: "absorptive" |
| EN ISO 11654 | Weighted sound absorption coefficient αw = 0.50 (LH), Class D |
| ITB Mould Resistance | Confirmed by Building Research Institute (ITB) per CUAP/ETA No. 12.01/21:2007 Annex B — result: 0 (no apparent growth of mycelium) in both test variants |



