A regauge is an essential health check for your whisky and should be done every 3 years once your cask is over 5 years old, and every year once it is over 15 years old. It determines the bulk Litres (the amount of liquid in the cask) and the ABV (alcohol by volume) to give the RLA (regauged litres of alcohol).
What is a regauage?
A full cask regauge has three steps:
- A sample is drawn and is tested to determine the alcoholic strength: the ABV, this must be above 40% for it to be legally termed whisky.
- The full cask is weighed, and the weight recorded, then the cask is emptied, and the unfilled weight is recorded. Subtracting the weight of the empty cask from the weight of the full casks gives the volume of liquid in the cask: the bulk litres
- Finally, the bulk litres and ABV are used to calculate the RLA. For example, if you had a bulk litres of 400 and a ABV of 60% then your RLA is 240 litres.