Step built in front of air vent

It’s never good to block an air brick in fact the only time I’d say it’s okay to block is if there’s risk of water Ingression (flooding). It’s good practice to keep the air bricks in use and you can get plastic extensions that would have brought it to the front of the step.

Air flow is paramount to prevent wood rot or mould.. If the house was built with vents, it’s at your (houses) peril to block them up. Easily enough to extent the vent though to the front of the step. Hope this helps!

As with most of the other answers it should’ve been vented and In pretty much the same position to allow the air to draw through from front to back,he either didn’t know this or couldn’t be bothered to organise it and it sounds like it would’ve been easy and add 30 mins and £10 to job 🤷‍♂️

Building control will expect air bricks to provide Continues air flow , under the ground floor from front to back of the house , and spaced at no more than 2mts apart , so over a run of 5mts you would have at least 3 , you may have sufficient air bricks to the either side of your new step , if not , it is possible to set air bricks into the side of the steps if You have more than one step , if not air bricks can be fitted to any room with a outside wall , of course if you have a concrete floor air bricks are not required, but air flow must be provided through other means ie windows .

I don't think it's big problem but why didn't he ex state the air brick 2 the outside of steps