A double vanity looks like a fair division of territory. Real mornings are less symmetrical. One person needs a basin for two minutes; the other needs somewhere to put six things while finding the seventh.
Watch the overlap
For a few ordinary mornings, notice when both people actually need running water. Separate that from simply being in the room together. Mirror space, lighting, and a useful clear surface may relieve the congestion without adding a second sink.
If the overlap is real, two basins can be worth the space. Draw them at their actual size with the taps, countertop edges, and nearby wall. Two people should be able to stand comfortably, not merely fit into a symmetrical elevation.
Open every drawer on the drawing
Ask for the internal cabinet arrangement with both traps and supplies shown. A long drawer front can conceal a divided interior. Reserve a place for the tallest bottles, spare towels, cleaning supplies, and the appliance that always arrives with a cable.
Kohler’s vanity installation guidance illustrates why plumbing and cabinet installation must be coordinated. Use the chosen vanity and basin specifications for the real layout.
An off-centre sink can be a useful answer
One basin placed to one side can leave a generous preparation surface, if the selected countertop and cabinet arrangement allow it. That is our design suggestion, not a universal prescription. Choose two sinks when the daily overlap earns them. Choose one when the second basin would mostly hold things you wanted to put on the counter.