Gas feed for duel fuel cooker, where it should go?

[crystal24uk]

Hi, could anyone advise where the gas feed for a duel fuel cooker should go. We are currently renovating our kitchen and they are doing the plumbing and electrics for the new kitchen before the insulation and plaster boards go on. I noticed there was no pipe there for the gas feed to the hob, is this correct? The builder said it will run along the wall when the kitchen unit are put in, but I really don't want a pipe running through all my new units. Please excuse my ignorance when it comes to this subject. Any advice would be gratefully appreciated. Thanx xoxo