Planning the lighting for a home: how many light sources per room

In construction or renovation, lighting is decided long before buying the slightest light fixture: at the moment the electrician runs the conduits. A forgotten light point is then remedied with chasing, exposed moldings, or extension cords. Here is how to design a lighting plan room by room, and the locations that are most often regretted.

Why everything is decided before the partitions

At the structural stage, adding a cable outlet costs a few dozen euros. Once the walls are painted and the tiles laid, the same operation requires chasing, filling, and repainting, or even an exposed installation.

It is therefore the only time when you can be generous at a low cost: it is better to plan an unused light point than a missing one. An unused outlet is neatly sealed with a cover, and remains available later.

The method: start with the furniture, not the walls

The classic mistake is to place a point in the geometric center of each room. Start instead by drawing the furniture: the table and its actual position, the bed, the sofa, the island, the desk. The light points are then placed above these elements, not in the middle of the walls.

It is this simple change of order that avoids the most widespread defect in new homes: a dining table lit obliquely by a point located 60 cm from the right place.

How many points per room?

Here are some common-sense guidelines, to be adapted to your plan:

• 25 m² living room: one central point, or two if the room is long, two wall outlets for wall lights, and two switched sockets for lamps.
• Dining room: one point centered on the table, never on the room; two or three aligned if the table exceeds 2.20 m.
• Kitchen: general lighting, power for under-cabinet lights, and one to three outlets above the island.
• Bedroom: one central point, two wall outlets on either side of the bed, and one switched socket.
• Hallway: one point every 1.80 to 2.50 m, switched with two-way switches.
• Entrance: one ceiling light and one wall outlet near the future mirror.
• Stairs: wall outlets along the flight and two-way switches at the top and bottom.

The rules for sizing the light fixtures themselves are in our guide on choosing the size of a chandelier.

The five locations that are regretted

In order of frequency: the outlet exactly above the dining table; the two bedside wall outlets, which free up the nightstands; the power supply under the upper kitchen cabinets, without which you work in your own shadow; the stair two-way switch; and an outlet above the future reading corner or desk.

These five points cost almost nothing to plan and transform daily use. The details per room are developed in our articles on lighting an island, bedroom chandeliers and wall lights and lighting stairs.

Controls: two-way switches, dimmers and circuits

Three decisions are made at the same time as the light points. The two-way switches, essential in circulation areas, the stairs, and the bedroom. The dimmers, to be planned at least in the living room, dining room, and bedrooms. And the circuit breakdown: being able to turn on the living area without turning on the whole room changes the evening comfort entirely.

Tell the electrician that the dimmers must be compatible with dimmable LEDs: not all are, as we explain in our article on bulbs, Kelvin, and the dimmer.

Plan for the load, not just the power supply

A light point must be able to support the light fixture that will come. If you are considering a glass chandelier weighing 10 to 25 kg, say so now: the support is installed before the false ceiling, not after.

The case of the stretch ceiling is the strictest: the reinforcement must be fixed to the original ceiling before installing the fabric, in the exact location. The complete constraints are in our article on fixing a chandelier to a stretch ceiling or plasterboard.

What to give to the electrician

A dimensioned plan is enough: the light points identified relative to two walls, the desired heights for the wall outlets, the location of the switches, and a note on the dimmers and circuits. Add photos of the planned light fixtures with their weight and diameter.

Also specify the presence of a DCL socket and, for wet rooms, the delimitation of the volumes: this is the subject of our article on bathroom lighting.

The most frequent mistakes

Centering all points on the rooms rather than on the furniture. Forgetting wall outlets, thus depriving yourself of wall lights forever. Planning a single circuit per room. Installing dimmers incompatible with LEDs. And saying nothing about the weight of the future light fixtures, then discovering that a support does not hold the planned load.

Choosing the light fixtures once the plan is finalized

When the points are in place, the choice becomes simple: you just need to respect the diameters and heights compatible with each location. Our blown glass chandeliers and our wall lights specify on each sheet the weight, diameter, and socket type, like this modern glass flower ceiling chandelier or this vintage red blown glass wall light. For the final installation, see our article on the connection and fixing of a light fixture.