ᐅ How many light fixtures should be installed in a 7-meter-long hallway?

Hello forum,
my house under construction has a hallway that is 7 meters long (7m) (length of living room + stairs going up + WC). The electrician planned for 2 light fixtures. That seems too few to me.
I plan to illuminate the stairs indirectly with the hallway lighting. Turn on the light at the bottom, walk upstairs in the hallway light, and turn off the light at the top again.

Edit: the hallway has no windows and is about 150 centimeters wide (150cm) (a classic corridor).

How many light points should I plan for the hallway?

It’s not that simple. It depends on several factors:
- Area
- Height
- Desired brightness
- Brightness of the lamps
- Beam angle of the lamps
- Reflective behavior of walls and floors
and so on.
However, two units seem rather few to me. More likely 3-5, depending on the factors mentioned above.

oh, this is getting complicated. I don’t have any measurable information about the light reflection properties of the floor (medium gray tiles) and I also don’t know the output of the lamps. I don’t even know which lamps will be used yet.

3 to 5 lamps seems appropriate to me. With 3 lamps, each lamp needs to illuminate about 120cm (47 inches) around, with 5 lamps only about 70cm (28 inches).

Since you don't know the exact points, you can only estimate.
If you make the lamps dimmable, it will be somewhat easier.

I have exactly 4 units over 7m (23 feet). It’s quite intense at 4000K and a 120° beam angle.

This is about as helpful as saying: "My car has standard features. I’m always amazed by the six-cylinder engine and automatic transmission."

As rick2018 already mentioned:

- Area
- Height
- Desired brightness
- Lamp brightness
- Lamp beam angle
- Reflection behavior of walls and floors

The reflection behavior of the floor has the least impact since it is usually about 2.5 meters (8 feet) away from the light source. What is more important is the appearance of the walls (and ceilings), whether they are smooth or textured, what color they have, and so on.

For example: If I plan four lights for a 7 x 1.5 = 10.5 m² (113 sq ft) area and assume 100 lux, I need about 250 lumens per light (with ideal illumination), which most inexpensive LEDs can provide. In public buildings, hallways are usually designed for 200 lux (which is already extremely bright for a home), but if my lights offer 1000 lumens each, then the two lights installed by the electrician are sufficient—provided we are talking about white walls that help distribute the light evenly. As you can see, it’s an equation with many variables, which fortunately are not unknown.