Skip to content Skip to navigation menu

Effective Salting

Mitigate the risk of snow and ice with our guidance on effective salting. Find out how salt works, salt spreading concentrations and more.

Salt is the most cost-effective de-icer available. In order to ensure roads, pavements and walkways are safe in all weather conditions, you can use salt to add grip to the surface to reduce the risk of slips, trips and falls. Both plain and treated rock salt it used as one of the most common forms of gritting as it can prevent ice forming on the surface and can also cause existing ice and snow to melt.

Gritting should be carried out when there is a risk of ice and snow, so keeping an eye on the weather forecast can be helpful. Salt needs time to melt ice and snow, early mornings or early evenings are the best times to grit.

To ensure you’re getting the best results, follow these tips for effective salt spreading.


How Salt Works

Salt, otherwise known as sodium chloride, has properties which make it an effective de-icer.

Salt is hygroscopic which means it actively attracts moisture from the surrounding air, absorbing and retaining it.

Once the salt has absorbed water from the air it will start to melt the ice. Salt solutions have a lower freezing temperature than pure water which makes them much less likely to freeze or re-freeze, and reduces the risk of slippery conditions from developing. The greater the quantity of salt added to the water or ice, the stronger the salt solution and the lower the temperature required to freeze.

Person using snow shovel to clear an area

When Is Salt Most Effective?

De-icing salt is more of the most effective ways to mitigate the risk of extreme weather. However, for the salt to effective melt snow and ice, there are two conditions which must be just right - moisture and concentration.

Moisture

As the temperature drops below freezing, the level of atmospheric humidity starts to fall.

When temperatures reach -5˚C, the effectiveness of de-icing salt is reduced by almost 70%.

Concentration

The greater the quantity of salt added to the snow or ice, the stronger the salt solution and the lower the re-freezing temperature. Use the suggested application rates below to ensure you are using the optimal amount of de-icing salt.

Suggested De-icing Salt Spread Rates (per m2)

Temperature Frost Snow
0˚C to -5˚C 10g to 20g 25g to 40g
Below -5˚C 20g to 30g 40g to 50g

Best Practice When Salt Spreading

The correct concentration of salt is one of two factors which determine how well it works as a de-icer. Use these tips to ensure you are salt spreading evenly and effectively, for the best de-icing results:

Spread Uniformly
Ensure the whole area is covered as evenly as possible. Check for any missed patches and avoid build-up in areas such as kerbs. This leads to salt wastage, which is poor practice both environmentally and economically.
Pre-Salt
Ice generally forms in the evening when the sun sets and the temperature drops. Keep your eye on the forecast and try to pre-empty the problem, putting out salt before ice forms. This can be done at a much lower application rate compared to using de-icing salt to melt existing snow and ice and is therefore more cost-effective.
Application Rates

For pre-salting, the ideal application rate is half a cup (approximately 20g) per square metre. Full salting usually requires one cup (approximately 40g) per square metre. If it rains after pre-salting and then freezes, you will have to salt again. Please note that the application rate will vary depending on the amount of frost or snow you’re dealing with.

Larger Areas

Salting large areas regularly - such as paths, pavements, car parks and playgrounds - can be a time-consuming and labour-intensive job. Working in the cold takes its toll on your body, making it harder to breathe. Using salt spreaders is a safe method of salting larger areas, reducing the amount of manual labour needed.


Salt Calculator App

Unsure how much salt you need for your site? Download our FREE Salt Calculator App so you can:

  • Calculate the amount of salt required for each site
  • Estimate the salt requirement for the season
  • Calculate how much salt to spread per application
  • Receive weather alerts based on personalised parameters

Download the app on App Store (Apple devices) or Play Store (Android devices).

iPhone using Salt App

More from Arco


Keep your people, visitors, and workplaces safe, whatever the weather with our comprehensive range of products.


All Expert Advice