There are three doors in the small area outside the storage room. Yes, they form an airlock – this is obvious from the way that with any one door open, the other doors behave differently from what is described below. However, the solution to the problem doors is not to relieve the air pressure in the airlock, it’s to shave the doors or doorframe to prevent the doors from sticking.

Storage door

This door opens outwards from the airlock. It closes with no problem, and with no slamming. Therefore there is no air pressure problem in the airlock that needs to be relieved.

Garage door

This door opens into the airlock, so cannot be affected by air pressure on closing. Note, however, that it sticks, badly, on both opening and closing. After opening around a centimetre, it sticks requires a firm tug to get it open. Similarly when closing, it sticks at the same point and requires a firm push to get it to close. Please see the below video:

External door

The external door opens outward from the airlock, and closes such that the door latch pops back out to prevent the door from opening again. Unfortunately, that doesn’t help: the swipe latch isn’t clicking, so re-swiping won’t re-open the door. The door is sticking, and you have to push the door fully closed to make the swipe latch click so that you can re-open it. You can hear the click in the below video: