So, you want to know how much salt you need for a parking lot. We will give you the easy answer just below, but you need to know the correct answer is “it depends.” So, look at the quick, baseline answer, then keep on reading.
2.3 pounds or more per 1000 square feet at 30° pavement temperature for a light snow or icing.
Now that you have a baseline, you need to remember that weather conditions and the type of salt you use will change how much salt you need.
The colder it is, the more salt you need. Going from 31° to 16° can potentially TRIPPLE your salt usage.
The more precipitation you need to cut through, the more salt you need. You need less for a ¼ inch of snow versus a ½ inch of ice.
If there is heavy icing, you will need more product. How much more product depends on how much ice there is.
If you salt without plowing, you will need more than if you plow and then salt.
Pretreating pavement with a brine solution can save you salt over pretreating by spreading rock salt.
Prewetting salt can reduce salt usage by as much as 30%.
Treating pavement with brine is usually best for pre-treating and for ice. Coarse salt usually cuts through snow compaction best and is often favored by contractors for knocking out snow.
All other things being equal, calcium chloride and magnesium chloride will need less salt than straight rock salt. Both magnesium chloride and calcium chloride have more melting power. For example, rock salt can only melt ice down to 15°F, but calcium chloride can work in temperatures as cold as -15°F.
In the end, you need to use your head. As you get experience, you will get a better feeling for how much salt you need to spread for each situation.
A few other points to remember.
Your biggest cost waster is overspreading by spreading more material than necessary or by placing material where it is not needed. When you put too much salt down, not only do you waste money, but that salt has to go somewhere so you likely just tossed your money (salt) in the river. Try to avoid overspreading.
Some people find it helpful to buy salt that has color so that it is easier to see when you spread it to help minimize over-application.
Quality applicators will spread evenly saving you time and salt. Don’t get a cheap spreader just so you can waste money on salt. This rule applies to everything from V-box spreaders to small walk-behind spreaders. Make sure you buy quality equipment.
Get your salt or deicing products from a good supplier. If you buy salt from us, we can give you a great deal on products and we can answer some of your questions about using de-icing chemicals (like calcium chloride) or what to do in specific weather situations.
The Wisconsin Salt Wise partnership has a handy little salt application calculator here. Be sure to scroll to the bottom of the page to find the calculator. The state of Minnesota has a handy