Cold weather working

3.2.7Admixtures

Admixtures shall be used correctly and in accordance with the manufacturer’s recommendations.

When using admixtures:

  • accelerators may assist the mortar or concrete to set before temperatures fall (admixtures do not prevent frost damage to uncured concrete or mortar)
  • plasticisers can entrain air during mixing to provide frost resistance to mature mortar and concrete
  • in cold weather, retarding agents should not be used as they can increase the setting times of cement
  • in cold weather, bonding agents may be ineffective
  • those containing calcium chloride should be avoided.