For vinyl windows, some manufacturers offer insulated mainframes and sashes to increase the window's insulating value. Look for an Expanded Polystyrene Insulation (EPS) option.
EPS is a thermoplastic, closed cell, lightweight, rigid foam plastic. It is the same material used in food industry packaging for its superior thermal insulating properties, and its solid form is used in rigid durable products such as TV and computer cabinets, appliances, toys, compact disc and audiocassette cases. EPS is also used for protective packaging and shipping of fragile items. As insulation in residential and commercial building products, EPS can provide an R-Value of 4 per inch (.25 U-Value per inch).
Expanded Polystyrene Insulation (EPS) provides:
- Long-Term Insulation Value
Offers stable, long-term thermal resistance, maintaining its insulating properties.
- Temperature Fluctuation
Able to withstand the rigors of temperature changes, assuring long-term performance & durability.
- Permanence
Compressive strength and dimensionally stable over time, maintaining its shape and size.
- Superior Moisture Resistance
Low water absorption rate makes EPS resistant to mold and fungus growth.
- 100% Recyclable
- CFC and HCFC FREE, so it's safe for the ozone!
- Recognized by GreenSpec® and Green Building.
Avoid window products that feature Polyurethane as an insulation option. Polyurethane uses CFCs (chlorofluorocarbons) in its manufacturing process, which deplete the earth's ozone layer! It also breaks down and loses volume, potentially collapsing in the frame hollows. Plus, a substantial portion of Polyurethane's insulating value is lost over time as it decomposes or "outgases."
