When does rainbow window film make rainbows?
Rainbows show in direct sun only. The sun has to land right on the glass, and then the mosaic splits it into color across your walls and floor. Here is how to tell whether your window gets that sun, and when.
You get rainbows when
- Direct sun lands on the glass
- Not on cloudy days
- Not at night, not on north-facing glass
1How it works
Direct sun in, color out
The film is a mosaic of small facets. When direct sun hits them, each facet bends the light a little and splits it into color, so small rainbows land on the walls and the floor.
Daylight from a cloudy sky is spread out, with no single direction, so it can’t make rainbows. That’s why the same window shows color one hour and none the next.
2Which windows
Which way does your window face?
For US homes, the direction a window faces tells you when direct sun can reach it.
East: mornings
East windows get direct sun in the morning, so that is when the rainbows show.
South: much of the day
South windows get direct sun for much of the day: the most rainbow time of any window.
West: toward evening
West windows get direct sun toward evening, so the color comes in the late afternoon.
North-facing glass gets no direct sun. There the film shows the soft stained-glass look and no rainbows. A porch roof, an awning, a tree or the house next door can also keep direct sun off a window for part of the day.
3Test your window
Watch the window for a day
Before you order, watch the window on a clear day. If sunlight falls through it onto the floor or a wall, it gets direct sun, and the film will make rainbows at those times.
Check in the morning, around midday and in the late afternoon. The sun sits lower in winter and higher in summer, so the sunny patches move through the year, and the rainbows move with them.
4Without sun
What it looks like the rest of the time
On cloudy days, at night and on north-facing glass the film is a soft stained-glass texture in one calm tone, with no rainbows. Same film, two real photos:
Rainbow film gives light privacy only: at night with the lights on inside, people and shapes can be seen. If privacy matters more than color, choose frosted, and see privacy at night.
5Order
Your window gets the sun? Cut it to size
The rainbow film is cut to the width and height of your glass, from $4.99 for the 12 in tier. The longest side picks the tier; Amazon shows the final price at checkout.
Before you buy
Frosted film blurs the view by day and at night, but at night with the lights on inside, someone close to the glass can show as a soft silhouette.
Rainbows show in direct sun only.
Neither film holds on heavily textured or pebbled glass.
More about the rainbow film
Photos, prices for every size and what is in the tube.