Gritting salt, brine and de-icing granules: what works when?
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- By Huchem UK
Spreading salt is the most effective way to prevent and clear ice on roads, car parks, paths and loading bays. But when should you grit, how much do you need, and when are urea or calcium de-icing granules the better choice? Read our winter guide.
Spreading salt is an effective method for preventing and clearing ice. In this article we explain why it works, when to grit, how much to use and when an alternative de-icer is the smarter choice.
Why salt works
Road salt is a de-icing agent. After spreading, the salt mixes with the snow or ice and forms brine. Brine has a lower freezing point than water, so the snow or ice melts. Standard rock salt works well down to around -6 °C to -8 °C. Below that it becomes slower and less effective.
Dry salt or brine?
Highway authorities increasingly spread salt "wet": the salt is moistened with brine before it is spread. It stays on the surface better, can be spread more accurately and starts working immediately. For smaller sites ready made brine in a sprayer is a very practical option for paths, entrances and loading bays: no scattered grit, no residue and a fast effect.
When to grit
If ice is forecast, grit preventively. We advise spreading a few hours before snow or freezing rain is expected. The precipitation then has less chance of bonding to the surface, and you need up to half as much salt as when you treat afterwards. Caught out by ice you did not expect? Then you can still grit curatively, but you will need considerably more salt to clear it.
How much salt?
- Preventive: 7 to 20 grams per m², a small handful per square metre.
- Curative: 20 to 50 grams per m², about two handfuls.
If snow has already fallen, clear it first and then grit. Spread as evenly as possible and store your salt in a dry place to prevent it from clumping.
When to choose de-icing granules instead of salt
Salt is cheap and effective, but it is corrosive to metal and concrete, damages plants and is not kind to paws. In some situations a different de-icer is the better choice:
- Urea de-icing granules are chloride free and therefore far less corrosive. Ideal around steel structures, near plants and lawns, on decking, at schools and care homes and anywhere pets walk. Effective to around -8 °C.
- Calcium chloride granules work at much lower temperatures (down to around -30 °C) and generate heat as they dissolve, so they act very quickly. The professional choice for severe frost and for sites that must stay open whatever the weather.
Our winter range
In the Huchem Winter Collection you will find road salt in 25 kg bags, a handy 1.5 kg pack for around the door, emergency salt, brine, urea and calcium de-icing granules in buckets and bags, plus de-icer spray and screenwash for the fleet. We wish you a safe, ice free winter.