Do I Need Window Film If I Already Have Low-E Windows?

Low-E coatings do a great job of keeping heat in your home, but do nothing to keep the sun’s heat and light out of your home. Low-E coatings provide little or no ultra-violet rejection, while most window films block 99%.

Windows with Low-E coatings can benefit from the installation of window film by reducing glare and blocking unwanted heat from entering your home, helping reduce energy costs year-round and providing a protective barrier to slow the effects of sun damage on furnishings.

If you don’t have Low-E windows, you can have a spectrally-selective window film installed to reflect long-wave infrared heat back into your livingspace, just like a Low-E coating. Like we stated before, these films also reject 99% UV light and reject heat from entering home – offering an average 35%-50% energy savings through the course of a year. If you already have double-pane glass and have heard of the benefits of low-e, having a spectrally-selective film installed is not only more cost effective than replacing your windows, but provides more benefits.

If you live in or around the Chicago area, visit our main website at www.precisefilm.com to arrange a free estimate for window film installation.

Tax Credit For Window Film?

Everyone asks us about the tax credit for window film. If you live in the northern portion of the US, unfortunately it’s a savings you probably won’t qualify for. The government requirements concerning energy tax credits for window film installed in the northern region of th US are as follows:

1) The windows the window film is being applied to must be double-pane insulated units

2) The windows must already have a low-e coating applied to them

3) The windows must have a vinyl frame

4) The installation must be in your principal residence

If you meet these requirements, you will eligible to get back 10% of the cost of the window film (not including the cost of the installation), with a maximum credit of $500 (This post updated 3/1/2011).

What Clear Window Films Can Do

With the hit the economy has taken, the use of  “spectrally-selective” films has seen a dramatic fall. However, the benefits of such films remains unchanged. Such films block UV light (99%), reduce solar heat and heat build-up, retain heat in winter, all while only reducing the visible light by an amount undetectable to the human eye.

Most commonly used in high-end installations, these films were designed to offer the most heat rejection and fade protection possible, without changing the view through the window.

The industry leaders of these films are V-Kool (V-Kool 70), 3M (Prestige 70), Vista (VS70) and Panorama (HiLite 70). This technological breakthrough was originally developed by V-Kool  in 1991, and still manufactures the highest performing spectrally-selective film in the world.

3M had the goal of making spectrally-selective films cheaper, and in some ways, succeeded. There are a couple of caveats: First, the optical clarity, or distortion impediment of Prestige 70 is moderate and adds a waviness to the glass. Some would argue that a film that costs $8-$12/sqft shouldn’t distort the view at all. As for Prestige 70 heat rejection, it is not constant, and on a double-pane installation will only perform between 44%-50% heat rejection, depending on the angle of the sun. Still, for those who want to save a couple bucks per foot, this is a way to go.

Panorama HiLite 70’s distortion impediement is undetectable, and its heat reduction performance on double-pane glass is 51%, but its quality that comes at a higher price than Prestige 70 ($10-14/sqft).

V-Kool 70 ($10-$14/sqft) distortion impediment is undetectable, and offers the highest heat rejection in its class on double-pane glass (56.2%).  

The manufacturer names and product ID’s are as follows (In order of performance
from best to worst):

V-Kool: VK70 | 56.2% TSER | 64.4% VLT

Panorama: HiLite 70 | 51% TSER | 64% VLT

Vista: VS70 | 48% TSER | 61% VLT

3M: Prestige 70 | 44% TSER | 61% VLT

(TSER: Total Solar Energy Rejected)

(VLT: Visible Light Transmission)