What is XPS Foam Insulation?
Expanded Polystyrene, referred to as XPS, is a closed-cell insulation product commonly used in remodeling and new construction applications. Due to the manufacturing process, XPS insulation is typically available only in standard dimension square or rectangular boards. Brands of XPS are generally recognizable by the color of the insulation: blue made by Dow, pink made by Owens Corning, green made by Kingspan, etc.
Extruded polystyrene (XPS) foam is rigid foam providing a strong, yet lightweight and flexible insulation solution that is resistant to water absorption, making it ideal for a range of building and commercial applications.
What is the XPS insulation board?
Extruded polystyrene (XPS) foam is rigid insulation that's also formed with polystyrene polymer, but manufactured using an extrusion process, and is often manufactured with a distinctive color to identify product brand.
Where Can XPS Foam Board Insulation Be Used?
Domestic and Commercial application areas for Extruded Polystyrene (XPS Foam) is as follows
- Cavity walls
- Over truss or Between rafters
- Suspended ceiling
- Inverted roofs
- Floors and Balconies.
The use of Extruded Polystyrene Foam insulation in commercial and residential buildings offers great flexibility, compatibility, and thermal efficiency for use in all areas of a building envelope.
Extruded Polystyrene Board is ideal for a range of uses – from wall and ceiling insulation, cool rooms & refrigeration, under the concrete slab (i.e. car park), and even for architectural modeling or hobby model making.
Is XPS Foam Board a vapor barrier?
Extruded Polystyrene (XPS Foam) has a perm rating of around 1, making it semipermeable. Thicker faced XPS is stronger and can have a lower perm rating, but it is still considered a vapor retarder, not a vapor barrier.
What is the R-Value of XPS Foam Insulation?
Extruded polystyrene (XPS) likewise improves with colder temperatures. Its nominal R-value is 5 per inch. This is the foam you see used a lot for exterior wall sheathing. It's generally blue (Dow) or pink (Owens-Corning). Extruded Polystyrene Foam will off-gas and lose some insulation performance over time - especially below-grade and when tested in real-world applications.
What is the difference between pink and blue foam board?
Brand Names. Both pink and blue foam boards are rigid insulation panels made from extruded polystyrene. The chemical composition, manufacturing process, and insulating capability of the two products are similar and the principal difference between them is that they are manufactured by two different companies.
Pink foam board is manufactured by Owens Corning, and it's marketed under several different brand-specific product names, including Foamular, Propink, Thermapink, and Insulpink. Blue foam board is manufactured by Dow Chemical Co., and it's marketed under the Styrofoam brand name.
What are the Benefits of XPS Foam?
- Lower heating and cooling Cost
- Won’t support mold or mildew growth
- Environment friendly
- No Leaks
When using Extruded Polystyrene Insulation (XPS), it is very important to install the product properly, as incorrect installation or exposed areas are violations of many building codes.
Extruded Polystyrene Board (XPS) Insulation
- Pros: Stronger and more water-resistant than EPS, better for below-grade applications
- Cons: Most products include strong chemical flame retardants. The blowing agents used will deplete the ozone layer
- R-Value: 5 per inch
- Cost: $0.61 Ex Vat per square foot for one-inch thickness
Above grade Extruded Polystyrene Insulation foam acts as a vapor retarder. When Extruded Polystyrene Insulation is taped it can act as an air barrier. The manufacturers and standardized testing state that it does not absorb moisture, nor is it affected adversely by it.
Thermal Resistance3, R-Value (180 days) minimum,
hr·ft2·°F/Btu (RSI, °C·m2/W)
@ 75°F (24°C) mean temperature
|¾" Thickness||4.0 (0.70)|
|1" Thickness||5.0 (0.88)|
|1½" Thickness||7.5 (1.32)|
|2" Thickness||10 (1.76)|
|2½" Thickness||12.5 (2.20)|
|3" Thickness||15 (2.64)|
|4" Thickness||20 (3.52)|
|@ 40°F (4.4°C) mean temperature|
|¾" Thickness||4.3 (0.76)|
|1" Thickness||5.4 (0.95)|
|1½" Thickness||8.1 (1.43)|
|2" Thickness||10.8 (1.90)|
|2½" Thickness||13.5 (2.38)|
|3" Thickness||16.2 (2.85)|
|4" Thickness||21.6 (3.80)|