D&D 5E Using "Always On" Trapfinding Houserule - Need help with Time Management

[Helpful NPC Thom]

So in my games I have used a houserule for a long time with the party rogue and traps. Instead of the Rogue going "I search for traps, I'm checking that for traps, is it trapped, etc etc", I just assume the rogue is always looking around for traps. When an actual trap is nearby, I give the Rogue an immediate check. If they succeed, they notice the trap. If they don't, they don't....and they don't get to try again.

Good policy.

So now to the big questions: For these kinds of dungeon room sizes, what do you think is a reasonable amount of time to pass to represent the searching of the rooms for traps?

I measure out time in intervals of ten minutes, just as Gygax intended. Assuming checking for traps, characters can move through one large sized room cautiously--that's moving quietly, checking for traps, etc.--every ten minutes. One large room equals two midsize rooms or three smaller rooms. Corridors follow the same principle.

If the characters want to speedrun, they can move twice as fast, but they aren't sneaking around or finding traps.