I was disappointed to find a "pizza steel" isn't supposed to be effective until above 270°C (a bit higher than a standard UK oven)? But as my oven operated with a US "broiler" style element and got up to 320°C it was working a treat anyway.A pizza steel
But running a domestic oven at that sort of temperature is a bit dodgy. The surrounding discolouration suggests "burn yer house down" so I upgraded to a small built-for-purpose oven. It has a stone ... 40mm thick! Taking a bit of getting used to (heats to 500°C!) but at least the house is safe from unplanned conflagration.