Updated: Feb 28, 2020
Light is a wondrous and glorious thing. It has so many definitions that we can scarcely take them all in. Light is life to all who embrace its warmth. We are children of the light… let us not live in the dark. It has both actual and metaphorical implications.
Today we are talking about lighting your home and how that light can bring your home to life.
You’ll find that I really like talking about lighting and all of its aspects. I don’t pretend to know all there is to know about light or lighting but I am fascinated by it.
We have a saying about lighting, “If you light everything, you really light nothing because nothing is illuminated”. Think about that. Our goal is to control what is illuminated, how it is illuminated and under what light it will be seen. Here is a good example of illuminating only what is intended.’
Going over the basics
There are three levels of light you need to be aware of.
When it comes to lighting, one thing is obvious, it helps you see your surroundings. Think of it like this, “In general, it lights up the room”. I am not being sarcastic when I say this, it’s how I started out remembering what its function was.
There are times when general lighting can be a bit boring, but in the hands of someone who knows how to play with light and shadow, who knows how to control the color of light and how to create a dramatic effect with it, well that’s when you can achieve simply stunning effects.
This is exactly what it sounds like, it is lighting designed to help you in your daily tasks. Commonly, in a home, we have a lot of task lighting in the kitchen and bathrooms. We also want to have it next to the bed or desk. These are obvious places for task lighting.
When thinking about a well-lit home we also want to think about places that may not be as obvious. You may need to have a lamp on your piano for your sheet music or you may need to light those two stairs in your hallway so the kids can get to the bathroom in the middle of the night.
Safety is one of the biggest concerns when thinking about task lighting.
I am reminded about when my husband and I were landscaping a very steep bank on our property, we had carefully planned out every detail and every step just right. Then it hit me that we hadn’t yet accommodated for getting around at night if we needed to. There was no way anyone could safely negotiate those stairs in the dark. We had to have exterior lighting.
Most of the time accent lighting is used to add flair to a design. For instance, lights inside of a bookcase are always special. Using spotlights on the path can be dramatic as well. Sometimes your accent light can do double duty. In the lighting plan in my kitchen, I use rope lighting in the ceiling tray to add effect but I also keep it on throughout the night for safety. I also like to keep my under counter lights on all day because it adds light at mid-height level. Plus it just pretty, and who doesn't love that!
Why is creating a lighting plan is important?
This seems like such a no brainer to me. It doesn’t matter how well-designed your room is, if you can’t see it, it isn’t well designed. Fail!
Of course you will want to go through your usual list of questions:
Who – will be using the space
What – type of space, commercial, garage, kitchen
When – day/night time activity, tasks performed here
Where – where is the light needed in this situation
How – calculating is key to a good lighting plan
How to calculate by volume and task
How do you know how much light you will need in a given space? Most people don’t think about it in terms of volume but you have to account for how much space there is in your space. If you have very high ceilings you will need more illumination than lower ceilings, even if you place the fixtures at the proper height.
Contrary to common belief, we do not measure light in watts. We measure light in lumens. A watt is a measurement of energy. A lumen is the measurement of the amount of light put out by a single candle. Nowadays incandescent bulbs are practically a thing of the past. You may even have a hard time finding “full spectrum” incandescent lights. Instead, what you’ll likely to see is compact fluorescents and LED bulbs that line the shelves. Long gone are the days of throwing your favorite brand of 60-watt light bulb in your cart and being on your way. No, you may not even be sure which funny-looking 60-watt light bulb is equal to the one you need.
Instead of thinking in watts we need to start learning lumens. But the real question is:
“How Many Lumens Do I Need To Light Up My Room?”
According to 1000bulbs.com they answer the question based on the IESNA (Illuminating Engineering Society of North America) Lighting Handbook:
Because different surfaces will reflect or absorb varying amounts of light, the amount of lumens is adjusted for this factor, of course there are other factors involved too.
They say that:
Floors: 20 Lumens per Square Foot
Tables and Raised Surfaces: 30 Lumens per Square Foot
Desks and Task Lighting: 50 Lumens per Square Foot
LET’S BREAK THAT DOWN
So let’s say you have an average 15’x18’ living room. That’s 270 sqft. At 20 lumens per sqft. that is 5400 lumens at the minimum. But that’s not all. It is useful to have a furniture layout to help you figure out your surface square footage needs. Let’s say you have a lamp for reading on either end a couch. A standard lamp will give you approximately a 4-foot circle of light. At 50 lumens per square foot that’s 200 lumens each.
If you are lighting a dining table you will want 540 lumens, for a 6x3 surface area of 30 lumens per square foot.
All this seems very confusing I know! In light of that (pun intended) let me show you how to calculate it the old-fashioned way.
Square footage x 1.5 = amount of watts. If you are calculating for a kitchen or bath it is “x 2.5”
This isn’t a foolproof, use in all situations kind of formula, but it will at least get you headed in the right direction.
So let’s say you have a standard size bedroom. 10’x 12’ = 120 sqft. 120 x 1.5 = 180 watts.
That means that you could have one ceiling light with two 60-watt bulbs and a table lamp on either side of the bed, with 40 watts each and you’ll be okay.
But let’s say you are lighting a kitchen that is 10’ x 15’. A kitchen will need to have a little more task lighting. Then it would look like this. 10’ x 15’ = 150 sqft. 150 x 2.5 = 375 watts.
The idea is to distribute the needed watts around the space and still have a sufficient amount of light where you are doing your tasks. So, what I might suggest would be to have a fixture that holds 200 watts above the island where you prep and one above the sink (100 watts) and another one over the stove. The tricky part is that fact that most fixtures only take 40 or 60 watt bulbs, so you have to plan your fixtures accordingly.
This would easily fulfill the requirements of the 375 watts. But what it hasn’t done is taken into account the three lighting categories. General, Task, and Accent. So you may want to add some under cabinet lighting. This would serve as both task and accent light.
Now I have to tell you that when I did my own kitchen lighting plan, I followed the complicated formula that I learned in design school and I have several lighting options and I have more light in there than normal. And I love it. We lovingly refer to our recessed lights as “The Sun” but hey, they are awesome. I love it because I don’t have them on unless I am doing some major cooking or it is a really dark day. We get a lot of those in Washington. The rest of the time the island light and the rest gives me enough to work with. But when I get really serious, I turn on the sun and I am happy about having installed them.
As you can see, this is a very complicated issue and I don’t have it all figured out either. Especially where it comes to using lumens vs watts. Look at it this way, now you know more than before. Plus, if you still have questions, you will at least have better questions.