When and How to Grit: A Winter Maintenance Guide for UK Businesses

Your Legal Duty as an Occupier or Employer

Businesses have a clear legal responsibility to manage winter slip hazards on their premises. Two pieces of legislation are particularly relevant:

• The Occupiers' Liability Act 1957 imposes a duty of care towards lawful visitors — customers, employees, contractors and delivery drivers. Occupiers must take reasonable steps to keep premises reasonably safe.
• The Health and Safety at Work etc. Act 1974 requires employers to ensure, so far as is reasonably practicable, the health, safety and welfare of employees. Slips and trips in icy or snowy conditions fall squarely within scope.

"Reasonable steps" does not mean you must guarantee that no one ever slips. It means you must have a systematic approach to winter maintenance and be able to demonstrate it. That is where gritting records become essential.

When to Grit: Don't Wait for Ice to Form

The most important rule of effective gritting is to apply salt before ice forms, not after. Rock salt works by lowering the freezing point of water — if ice has already formed, it takes longer to act and requires higher application rates to be effective.

The trigger point for gritting is when ground surface temperatures are forecast to drop to 0°C or below. As a practical guide:

• Grit when air temperature is at or below 2°C and falling
• For overnight frosts, apply salt in the early evening, before temperatures drop, rather than waiting until morning when ice will already have formed
• After snowfall, clear as much snow as possible before applying salt, as a thick layer of snow significantly reduces salt effectiveness

The Met Office provides road surface temperature forecasts that are useful for planning. Local authority websites often publish gritting route updates which, while focused on public roads, give a useful indicator of when conditions are expected to be severe in your area.

What to Use: Choosing the Right Material

Not all gritting products are equivalent. The main options are:

• Rock salt (sodium chloride): the standard product for most applications. Effective down to approximately −8°C. Treated rock salt includes anti-caking agents that prevent clumping in storage and improve spreadability in cold conditions.
• Fine white salt: a purer, finer-grained product preferred for pedestrian areas on commercial properties where aesthetics matter, such as retail entrances, hotel approaches and office courtyards. It leaves less visible residue.
• Grit (sand and salt mix): provides traction as well as ice-melting properties. Particularly useful on steep ramps or heavily trafficked vehicle areas where extra grip is needed alongside de-icing.

For most business premises, treated rock salt is the most practical and cost-effective choice. Store it in a waterproof grit bin with a secure, close-fitting lid — salt draws moisture from the air and will clump and lose effectiveness if stored in an open or leaking container.

Application Rates: How Much Salt to Use

Using the right quantity of salt matters. Too little and the treatment will be ineffective; too much is wasteful and can cause long-term damage to surfaces and nearby vegetation.

• Pre-treatment before freezing: 20–30 grams per square metre is typically sufficient
• After snowfall: increase to approximately 40 grams per square metre
• Spreading width: a standard pedestrian spreader covers approximately one metre per pass

Mechanical spreaders — even simple, hand-pushed pedestrian models — deliver more consistent coverage than hand-scattering and reduce the total amount of salt needed. For larger car parks and yards, vehicle-mounted or tow-behind spreaders make light work of large areas.

Priority Areas: Where to Grit First

Most businesses cannot treat every external surface simultaneously. Identify and prioritise the areas that pose the highest risk to the most people:

• Pedestrian entrances and exits — including the approach from car park to door
• Steps and ramps, which become particularly hazardous when icy
• External walkways and footpaths between buildings
• Car park pedestrian routes and crossing points
• Loading bays and delivery access points

At entrances and lobbies where wet footwear is brought indoors, anti-slip safety matting provides an effective indoor complement to your external gritting programme — tracked-in water from boots significantly increases the risk of indoor slips.

Map out your priority gritting routes before winter arrives and assign responsibility to a named individual or team. This prevents confusion when conditions deteriorate suddenly or when the person who normally handles gritting is absent.

Grit Bins: Siting and Specification

A grit bin is only useful if it is in the right place and properly maintained. Key considerations:

• Location: site bins close to priority gritting areas so that whoever is responsible for treatment can access salt quickly without first having to cross icy ground
• Visibility: mark the bin clearly — with paint, signage or a brightly coloured lid — so it can be found quickly in poor light or heavy snow
• Capacity: choose a bin large enough to hold sufficient salt for your needs throughout a sustained cold spell without requiring daily refilling; most standard bins hold between 200 and 400 litres
• Lid seal: check that the lid closes securely and keeps water out
• Stock before winter: fill bins before the first cold weather is forecast — suppliers can run short during cold spells, and waiting until you need salt is a risk you can easily avoid

Record Keeping: Your Evidence if a Claim Is Made

If someone slips and falls on your premises during winter weather, the first thing insurers and solicitors will request is evidence of your winter maintenance regime. A simple log noting the date, time, areas treated and the name of the person who carried out the gritting is often sufficient to demonstrate that reasonable precautions were taken.

Keep records throughout the winter season, even on days when no gritting was carried out. A note that conditions were assessed and no treatment was required is also valuable evidence of a systematic, consistent approach. Without records, it is your word against a claimant's. Consider also whether indoor surfaces at entry points are protected with floor safety matting — tracked-in snow and ice melt can significantly increase indoor slip risk during cold spells.

Pre-prepared gritting logs — with columns for date, time, conditions, areas treated and operative signature — make record-keeping straightforward and take the effort out of good practice.

Explore our full range of grit bins and winter maintenance equipment, available in a range of capacities for commercial and industrial use. Stock up before the season arrives to ensure you are prepared when temperatures drop.