Residential Window Film

Solar heat gain through south and west facing windows is a serious problem for apartment facilities in Orange County. Many properties experience costly overheating problems. Nation wide, uncontrolled heat gain is one of the most significant factors in decreased tenant retention.

In California the use of heating, ventilating and air conditioning (HVAC) systems to mitigate solar heat may cause power blackouts this summer. In the rush to conserve energy, few realize that a facilityâs windows are the biggest contributor to heat gain and the need to run HVAC systems. Block heat from entering windows and it is possible to run HVAC systems less, reduce energy bills and perhaps avoid power blackouts.

Large expanses of glass raise temperatures and air conditioning bills. Solar heat gain can lead to the following problems:

• Inability to use space near windows;
• Frequent use and replacement of HVAC equipment;
• Fading and heat damage to furnishings and carpets;
• Uncomfortable tenants.

Solutions To Overheating

A window should let in desirable energy (daylight) and block unwanted solar energy (near infrared heat) which causes overheating. Heat gain can be mitigated by replacing existing glass with expensive solar control glass. At far less cost, solar control films can be applied to existing windows.

Tinted or mirrored window films block unwanted heat but reduce visible light and darken interiors. Buildings with dark films on their windows may have to increase lighting to compensate for the decrease in visible light. The additional use of electricity for lighting (which increases energy costs) may actually increase temperatures requiring more air-conditioning. Increased utility costs will be passed on to tenants which subsequently defeats the major benefit of the film - cost savings.

The best solution to overheating - spectrally-selective clear film.

Transparent, almost colorless spectrally-selective applied window film offers the best ratio of visible light transmission to heat rejection. Clear and almost colorless films do not change the aesthetics of existing glass be it clear or tinted. These films are constructed with a scratch resistant coating on one side and an adhesive coating on the other, allowing for retrofit application to existing glass.

The following table shows how different kinds of glass and applied films transmit light and heat.