How to use light in your interior design

At Lampmasters, we see how difficult it can be to find the lighting that fits your wishes and needs on a daily basis. You fall in love with a lamp and buy it, but when you get home, it doesn’t look like you imagined it would. If that’s a scenario you recognise and you’re familiar with the challenge of finding the right light for your home, we’re here to help with some simple rules of thumb.
Incorporate ‘lighting layers’
In lighting design, we have a term called ‘lighting layers’—in other words, decorating a room with multiple sources of light to create a different illumination. When you decorate a room using lighting layers, you work with the basic ambient light, zones with more direct and functional light, and supplemental spot lighting.

The basic ambient light engulfs the whole room. It comes from windows, lit walls that reflect light, or lamps that shine in all directions through a shielded light source.

Zones with more direct and functional light are larger surfaces and areas that are better lit than the rest of the room. It’s a good idea to have these zones over kitchen counters, dining tables, and reading corners.

Supplemental spot lighting comes into play when you place small sources of light in dark areas. This could be a small table lamp on a shelving system, candles on the windowsill, or a single pendant with a visible light source in a corner.

When we use all three kinds of lighting in the same room, it stimulates us positively. To help clarify the use of lighting layers in interior design, we’ve outlined some examples below.
Do a rough light calculation before buying
Doing 100% accurate light calculations is relatively complex, and you can’t do them unless you have the right tools. That said, you can easily do a rough calculation to determine whether a lamp gives off the desires amount of light.

The first thing you need to look at is the given amount of light. You’ll find this under the technical specifications, where the ‘lumen’ (abbreviated ‘lm’) value describes the amount of light. If you only know the light source (bulb) used, you can use the technical specifications of the source to find the lumen.

If you use halogen bulbs, these are the rough values:
15W = 140 lumen
25W = 250 lumen
40W = 470 lumen
60W = 800 lumen
75W = 1050 lumen
100W = 1520 lumen

Aside from lumen, you need to know how much light you need. Do you want work light or cosy ambient light in the space your calculations are based on? There are specifications to help you determine how much light makes up ‘work light’. These specifications are known as ‘lux’ (abbreviated ‘lx’). Lux is the unit for lumen/m2.

Work light = around 500 lx
Generic dimmed light = around 200 lx

Finally, you need to know the size of the room or the surface, depending on whether you want to light up a dining table or an entire living room.

Once you know the lumen (lm) value of the lamp, your own lighting needs (lx), and the size of the surface you want to illuminate (m2), you can use the formula below to start your calculations. This will help you figure out which or how many lamps you need to satisfy your exact needs:

lm = lx * m2

We’ve done two sample calculations for clarification:

The living room
You have a 20 m2 living room, and you want a general light level of around 200 lx. You can use the formula to calculate how the lumen value you need. The calculation would be as follows:

200 lx * 20 m2 = 4000 lm

In other words, you need 4000 lm to illuminate your living room properly. These 4000 lm can easily be split across multiple lamps. If you follow the first piece of advice, doing so is a good course of action. You could use a glass pendant of 1500 lm to create ambient lighting to all sides, a table lamp of 300 lm to light up your shelves, and two floor lamps of 1100 lm each to take care of the rest.

The dining table
In this second example, you want to know how many lamps you need to light up your dining table. Your dining table measures around 2 m2, and you want a good work light of around 500 lx in this area. For this scenario, the calculation would look as follows:

500 lx * 2 m2 = 1000 lm

So, the lamp (or lamps) needs to provide a total value of 1000 lm. Whether this is spread across three lamps of 300 lm or a single lamp of 1000 lm doesn’t have a significant impact in terms of fulfilling your specific lighting needs.
Make the walls reflect the light and lift the room
Our third piece of advice is simple, but it’s something most people don’t think about. To some extent, all surfaces reflect the light that shines on them. Light surfaces reflect more light than dark ones. White surfaces, whether matte or glossy, reflect more than 90% of the light they receive. In other words, you can use large, light surfaces to create light in any area.

Rather than thinking you need to light up a whole area, you can create a relaxed indirect glow by lighting up your walls. If you have a dark corner in your living room, you can opt for a floor lamp with up-light. The lamp allows you to use the white surface of the ceiling and the two surrounding walls to create light. Doing so makes the room seem bigger without blinding anyone, and you cut out the down-light you would otherwise get from a lamp with a downward-facing light.

A more modern solution that works with indirectly reflected light is recessed spotlights. These are tilted to focus on the walls. Spotlights are a good solution for narrow hallways as they make the hallway seem wider without blinding or taking up unnecessary space.