The sun is the best deicer you don't pay for. Knowing where it hits and where it doesn't tells you where to put material first.
Solar gain
Dark asphalt absorbs sunlight, so a sunny pavement can run well above the air temperature, and salt works noticeably better there in daylight.1 The flip side: shaded walks, the north sides of buildings, canopies and parking ramps get none of that help, and they're where ice lingers and refreezes first. Overcast days and low winter sun angles in December and January cut solar help sharply.
What colored salt actually does
Treated salt is usually dyed (blue, green or reddish) so you can see it.2 Be skeptical of claims that dye melts much more ice by absorbing sunlight. The real benefits are practical:
- You can see coverage. Operators can see gaps and stop double-dipping, which cuts over-application.
- Clients can see the work. A blue entrance tells the property manager the walk was done.
- Photos prove it. A time-stamped photo of colored material on the walk is far stronger documentation than a photo of wet pavement.
The liquid treatment on the salt is what makes it work colder and bounce less. The color makes it visible.2
Next in the guideDocumentation for slip-and-fall liability →