I stand corrected Mike.
When I was an apprentice in a large engineering firm, they made the tea ready-milked in an urn in the works canteen at lunch-time, served from a tap at it's base. Terrible stuff, like milk in a flask of tea, but worse.
I'm sure there must be a trendy 'caff' in London's East-End, perhaps near Old Street, that sells 'Builder's Tea'...Builder's Chai Latte anyone? 'Will that be caf or de-caf Sir ?'
Off for a ride with Cyril now, enough o' this splother.