Cask venting & conditioning

Venting lets the carbon dioxide still being produced inside a cask escape in a controlled way, so the beer settles to the right condition instead of gushing or going flat.

  • Soft spile first to vent, hard spile once the bubbling has stopped
  • If pressure builds again, go back to a soft spile rather than forcing it
  • Wooden spiles are single use u2014 porous wood cannot be sanitised

Showing all 13 results

Showing all 13 results

A cask arrives lively. A hole is made in the shive and a soft, porous spile is fitted, which lets gas bleed off while the beer keeps working. That can take anything from a few hours to a couple of days depending on the beer and the cellar. Once the bubbling stops, the soft spile is swapped for a hard, non-porous one, which seals the cask and holds the condition that is left in the beer until it goes on service.

How to choose

What to know

The judgement is in the timing. Pull the hard spile in too early and the beer keeps fermenting and comes out over-lively; leave the soft spile in too long and you vent away the condition and the pint is flat. If pressure starts building again after the hard spile goes in, the answer is to go back to a soft one for a while rather than to fight it.

What to know

Wooden spiles are a single-use item. They are porous by design, which is precisely why they cannot be properly cleaned, so they go in the bin after one cask rather than back in the drawer.

Common questions

What is the difference between a soft spile and a hard spile?

A soft spile is porous and lets gas escape slowly, which is what you want while the beer is still conditioning. A hard spile is solid and seals the cask, holding the remaining condition in the beer until it is served.

How long should a cask vent for?

Until the bubbling stops, which depends on the beer and how warm the cellar is. It can be a few hours or it can be two days. Time is a poor guide u2014 watch the cask, not the clock.

Can I reuse a wooden spile?

No. Wood is porous, which is exactly what makes a soft spile work, and it is also what makes it impossible to clean properly. Use a fresh one on every cask.

Have a look at

Cellar equipmentBeer engines & accessories