Four people, one flat, three different shift patterns. It works, but not by accident. The flats that run smoothly are the ones where the awkward details — who sleeps where, whose food is whose — were settled in the first week instead of argued over in the third.
Put the night worker in the room furthest from the kitchen, the front door and the washing machine. Those three wake people up far more reliably than street noise, which is easier to cover with a fan.
If two people share a room, pair opposite shifts. One leaves as the other comes back, so the room is only contested for a few minutes a day. Two day-shift workers in one room means neither ever has it empty.
Keep the head of the bed off the shared wall, and leave a gap to the door so nobody climbs over anyone at five in the morning.
Light is the easier problem. Blackout curtains on every bedroom window, a towel along the bottom of the door, and tape over the standby lights on the router and television.
Noise needs an agreement rather than a gadget:
One bathroom and four people on different rotas is the most common source of friction in a shared flat. Fix it with a written window: whoever is leaving for a shift gets the bathroom first for twenty or thirty minutes, and everyone else knows the order.
In the kitchen, agree who cooks when and who washes up after. Cooking at eleven at night is fine as long as the pots are done before bed, not left for the morning shift.
Shared fridges fail for one reason: nobody knows what is theirs. Give each person a shelf or a labelled box, and write the date on anything that has been opened. A marker pen next to the fridge settles most arguments before they start.
For cleaning, split by area rather than by week. One person owns the bathroom, one the kitchen, one the floors and the rubbish. Area ownership is easier to remember than a rota nobody opens. Keep one shared list for soap, tissue and bin bags.
Agree quiet hours in writing, typically ten at night to seven in the morning for noise, with a separate understanding for anyone sleeping outside that window. Pin it up and revisit it when the rotas change.
The other thing worth writing down is who works when. A shared note is enough at first, but it goes stale after the first swap. Many flatmates use Shiftat-E to log their shifts and hours, so each person can see their own pattern and say plainly which nights they will be out of the flat.
Once the week is visible, the flat stops negotiating every shower and every late dinner and starts planning around them.
If you are setting up a flat with different shifts, start with the two sheets nobody wants to write: quiet hours and a shift record. Log your shifts, hours and planned leave with Shiftat-E on Google Play.