A shelf above the machines is the highest-value change you can make in a small laundry room. It gets every bottle off the appliance lids, creates the folding surface the room never had, and costs less than a takeaway. It is also the change people most often get slightly wrong, because five constraints decide where that shelf can go, and the galleries of pretty laundry rooms mention approximately none of them.
Short answer: Mount a shelf 40 to 45 cm above a front loader, or above the fully open lid arc of a top loader, and keep it 25 to 30 cm deep so it does not crowd you. Check five things before drilling: lid clearance, access to the water valves, vibration (add a lip or rail), dryer heat rising, and whether you can still pull the machines out for service. If you cannot drill, use a freestanding over-machine unit instead.
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