The double sink is one of the elements that sells best in renovation catalogues. It looks great in photos. And when it works well in real life, it significantly improves cohabitation as a couple or in families with older children.
But it’s also one of the elements most frequently installed badly. Insufficient space, poor lighting, one mirror for two people, plumbing that unnecessarily complicates the renovation.
When it genuinely makes sense
Couples with different routines
If two people get up at the same time and share the same bathroom, sink time every morning becomes a bottleneck. Two sinks eliminate that problem.
Families with teenagers
Same logic applies. A main bathroom with a teenager who occupies it for 30 minutes every morning is a family logistics problem. Two sinks resolve it.
When the bathroom is large enough
Here’s the key many people ignore: a double sink in a small bathroom is a mistake. It leaves no room to move, the atmosphere feels cramped, and there’s insufficient storage for two people. In bathrooms under 6-7m², double sinks rarely make practical sense.
Minimum space required
For a functional, comfortable double sink setup:
Minimum vanity or worktop length: 140-150cm. With less than that, the sinks are too close together for two people to use simultaneously in comfort.
Ideal width: 160-200cm. With 160cm you have two 45cm sinks with 70cm of central elbow room. With 180-200cm, the result is noticeably more comfortable.
In summary: you need a bathroom of at least 8m² for a double sink to make real sense, and with 10-12m² or more is when it really shines.
Plumbing: the most complicating factor
For two sinks, you need two cold water inlets, two hot water inlets and two waste pipes. If there’s only one current supply point, you have two options:
Option A: branching from the existing supply. The plumber makes a manifold feeding both sinks from a single entry point. Works well if water pressure is sufficient.
Option B: run a new supply from the main column. More work, more cost, but a clean and robust installation. If you’re doing a full bathroom renovation and opening walls, this is the opportunity to do it properly.
The additional plumbing cost for going from one sink to two ranges from €150-300 in a standard renovation.
Types of double sink vanity
Continuous vanity with two integrated sinks
The cleanest visual solution. A long unit (160-200cm) with two integrated or countertop sinks, a large drawer under each sink and central storage. Roca, Noken, Duravit and Burgbad have specific collections for this format.
Approximate price: €800-2,500 for the set (vanity + two sinks + taps), depending on brand and quality.
Two separate individual units
Two independent modules with their own sinks and storage. Can have the same design or be deliberately different.
Approximate price: €400-1,200 per module, or €800-2,400 for the pair.
Worktop with countertop sinks
A porcelain, marble or wood worktop on a vanity structure, with two countertop sinks. The most common format in design bathrooms and hotels.
Approximate price: worktop (€60-150/linear metre), countertop sinks (€80-250 each), vanity units (€300-800 each). Total: €700-2,000 without installation.
Common mistakes to avoid
One mirror for two sinks
The most repeated error. A large single mirror for both sinks means both people see each other while looking at themselves, which is uncomfortable. The correct solution is two mirrors, one centred over each sink, or a continuous wall-to-wall mirror.
Insufficient or centralised lighting
A single ceiling light centred between two sinks leaves both users in relative shadow. Double sink lighting needs frontal light over each sink — side wall lights by the mirror or integrated LED strips.
Single water supply with low pressure
Two taps running simultaneously from the same supply can suffer from low pressure. The plumber should verify this when doing the renovation.
Vanity too short
Less than 140cm of length means the double sink isn’t functional for simultaneous use.
The incremental cost of a double sink
The cost increase comes from four factors:
- Plumbing: €150-300 more for the second supply
- Longer vanity or second module: €400-800 more
- Second sink: €80-300 more depending on quality
- Second tap: €80-250 more
Approximate incremental total: €700-1,650 over a single sink installation.
Frequently asked questions
Can I add a second sink without renovating the entire bathroom? Yes, though it’s more complex. It requires opening the wall for plumbing, installing the new vanity and resolving the wall finish. Cost around €600-1,200 depending on the work needed.
What’s the best tap for a double sink? Same as for a single: Grohe, Roca, Tres, Hansgrohe. The important thing is that both taps are identical or from the same design family for visual coherence.
To see how a double sink would work in your bathroom layout, contact us at Reformarte and we’ll provide a 3D proposal. Use our bathroom renovation calculator for a total budget estimate.
