Off WIKIPEDIA

Vault (architecture), an arched form above an enclosed space

Vaults, a number of pubs, not all having vaults as an architectural feature; the word also had the general meaning of 'storeroom'.[16] By extension 'the vaults' was formerly used to designate a particular type of bar. At a time (mid 19th-mid 20th century) when the several areas in a Pub served different clientele, 'the vaults' would cater largely for working-class drinkers and would most usually be men-only.

I suspect a lot of pubs that used Vault in the name and would once have been beerhouses and couldn't be called hotel, inn or tavern because of different licences that may have been used for each type.

some Birkenhead ones were

Alma Vaults Earl street
Eclipse Vaults Meadow Lane
Shamrock Vaults crossed out Vine street
Old Calabar Vaults Warrington street
Haymarket Vaults Oliver street
Wellington Vaults Earl street
Grosvenor Vaults Earl street
Cambrian Vaults William street parallel to Henry st and side of market
Globe Vaults crossed out Egerton street by Tunnel road
Bird in Hand Vaults Chapel street
Central Vaults Grange Road
Why Not Tavern Henry street
Hope and Anchor Vaults Hope street
Victoria Vaults New Chester Road
Greyhound Vaults Oliver street
Victoria Vaults Oxton Road
Royal Oak Vaults Park street
Grafton Vaults Thomas street

The Shamrock was in Price Street, which backed on to Vine Street. Then of course there is the Vittoria Vaults (The Piggy).
Nice one derek.

Derek,

You seem to be doing a lot of vaulting. Are you having an alcohol problem, or just training for the Olympics? :-)

The Copperfield, at the junction of Market Street and Hamilton Street, was called the Hamilton Vaults up to the early 1970s.