Natural lighting has inspired architects for millennia, including modern legends Le Corbusier and Louis Kahn. But, while these fantastic artists created masterpieces, we lesser mortals may be happy with natural lighting for energy efficiency, environmental sustainability, and financial savings.
Optimizing natural lighting for efficiency, also known as daylighting, reduces cooling and heating costs and increases energy bill savings further by decreasing the number of hours you need to use artificial lights. However, it would be best if you used natural lighting correctly for it to be efficient.
Using natural lighting for efficiency isn’t simply about glass windows, skylights, and other fixtures. There’s more to daylighting if you want to truly leverage the power of natural lighting for efficiency.
Read on to learn how to use natural lighting in this ultimate guide to saving money.
How To Save With Natural Lighting
Le Corbusier championed five principles of architecture in his designs, and you can use any or all of them to save with natural lighting.
Of course, you won’t have absolute freedom to consider every concept due to many constraints, such as:
- Climate – based on your location and the energy efficiency you desire.
- Size and type of house – construction, floor plan, orientation, stories, etc.
- The scope of your project – new or old home, remodeling, retrofitting, etc.
Nonetheless, here are Le Corbusier’s five principles:
- Pilotis – grids of columns replacing traditional load-bearing walls
- Free plan – flexible floor plans for adaptable living spaces
- Roof gardens – to regulate temperature and also moisture
- Horizontal windows – to facilitate natural light and better views
- Free facade plans – to connect or separate the exterior and interior elements
You may or may not consider grids of columns to replace load-bearing walls. Also, a free or open floor plan is easier said than done—roof gardens aren’t viable in many climates and sloping surfaces.
But you can explore facade plans and horizontal windows for natural lighting. A passive solar design is an even better and more holistic approach, which uses natural lighting for energy efficiency and helps reduce your cooling and heating needs.
Now, let’s take a look at the essential features of a home with efficient natural lighting.
A Bespoke Passive Solar Design for Your House
This characteristic involves regulating natural lighting based on your needs. For example, a house in the tropics shouldn’t have a lot of natural light during the summer because it will spike the cooling requirements, achieving the opposite of energy efficiency.
Likewise, a lack or blocking of natural light in colder climates increases heating costs. Therefore, you have to optimize natural lighting in a way that works for your house, and the only sustainable approach is a passive solar design.
Any bespoke passive solar design will prioritize natural lighting optimization by default, which will help you increase your home’s energy efficiency, facilitating significant savings on your electricity bills.
Here’s how you can save with natural lighting for efficiency using a passive solar design:
Optimized Use of Direct and Indirect Natural Lighting
Suppose you can’t accommodate a comprehensive or holistic passive solar design to optimize the natural light in your house. The reason could be anything from your home’s orientation to its structural attributes. Also, a complete passive solar design is an expensive proposition.
In such scenarios, you can use direct and indirect natural lighting with a combination of fixtures for exposure and shading, depending on your needs. This setup involves considering the relevance and utility of the windows in your house.
Here are a few practical ways to use windows for direct natural light:
- You may opt for horizontal windows instead of more conventional vertical ones.
- You can position the windows higher or lower depending on the latitude and orientation.
- You can install skylights in the rooms on the uppermost floor and wherever possible.
- Bay windows are a viable option; they can be as tall and wide as you desire.
- Clerestory windows are a great option if the sun’s angle of incidence warrants them.
Sometimes, conventional windows don’t have sufficient clearance outside for direct sunlight if the angle of incidence is too low. This problem may be more common on ground floors with adjacent houses blocking the sun. Clerestory windows can make a difference in such homes.
Likewise, you can combine bay windows and skylights for rooms on the ground and first floors if you have a second story. You need a similar approach while considering shades to use indirect natural lighting. Typical shading tactics, such as blinds, curtains, etc., aren’t your only options.
For instance, you can consider a deep or shallow roof overhang to optimize direct and indirect natural lighting based on your climate and energy efficiency requirements.
Using Classic Methods and Daylighting Systems
Shades and windows are the classic methods of managing natural light in a house. However, you aren’t confined to these solutions to use indirect natural lighting for efficiency, and you might wish to consider dynamic and responsive daylighting systems if they are viable.
Generally, classic daylighting methods include the following:
- A building footprint based on natural light optimization
- Window-to-wall ratio, depending on climate conditions
- Heavy-duty glazing for windows for energy efficiency
- A fenestration design that is optimized for daylighting
- Shades, from artificial to natural options, as required
- An interior design to make the most of natural lighting
If you assess these conventional solutions, most of them align with Le Corbusier’s principles. A flexible or open floor plan naturally paves the way for an interior design to optimize daylighting.
That said, these traditional methods work even better with the following daylighting systems:
- Tubular systems
- Horizontal systems
- Vertical systems
- Fiber optical setup
These setups use daylight redirection devices. Such systems can be dynamic and responsive to the extent of tracking the sun and continuing to redirect natural light throughout the day.
Tubular daylight devices are also known as solar tubes. These ocular tubes, usually fixed, have an aperture for exposure in the roof to collect and redirect sunlight. The light gets reflected down through the tube and diffused into the indoor space.
Horizontal systems collect and redirect natural light from and through the external walls. While they are new, vertical daylighting is more prevalent, like solar tubes. These vertical setups use a tracking system to collect optimum light and redirect it using lenses and mirrors.
Fiber optical systems also use lenses and mirrors, but they are more expensive than a vertical setup. Plus, vertical configurations can work with diffused light in an indirect natural lighting system.
Natural Lighting Tips and Tricks
Using natural lighting without a plan can have unpredictable effects on your home’s energy efficiency. Hence, it would be best to optimize daylighting as ideally as possible.
Here are a few helpful tips and tricks to optimize natural lighting for efficiency:
- In colder climates, maximize natural light exposure through south-facing windows during winters. Even in warmer regions, south-facing windows aren’t an issue in the summer because they don’t let much direct sunlight in, and shades can regulate it.
- Minimize sunlight exposure through windows to the east and west in hot climates to reduce glare and the heating effect of solar radiation. You should decide on the use of roof overhangs or any shading based on the latitude and orientation.
- Windows facing the north can have maximum exposure to natural light without the heating effect and, thus, the energy inefficiency inside a house. The converse is true for homes in the southern hemisphere.
- All windows and other mediums of exposure should be insulated so that direct and indirect natural lighting optimization is efficient. Double-glazed glass and insulated skylights are common examples.
- Natural lighting should use passive solar design components, like roof overhangs and shading, to improve both direct and indirect sunlight optimization. A complete passive solar design with absorbers, distributors, and thermal mass is ideal.
- Use daylighting systems – like dynamic and responsive devices – to collect and redirect more sunlight. Leveraging both direct and indirect daylighting will improve energy efficiency beyond the typical levels.
Note that a passive solar design is desirable and more effective in optimizing natural light for efficiency, but it is not a precondition. That said, natural lighting and passive solar don’t substitute insulation and other proven and standard measures for energy efficiency.
Pros of Natural Lighting for Efficiency
Here are the benefits of optimizing natural lighting for improved energy efficiency in your house:
- Natural lighting reduces seasonal cooling and heating costs by optimizing solar gain in hot and cold climates, respectively. In addition, a passive solar design facilitates regulatory options, including shading, to control the exposure to natural light.
- Natural light increases annual energy bill savings by reducing cooling, heating, and artificial lighting costs. Generally, cooling, heating, and artificial lighting account for ~35% of energy bills, which natural light and solar heat can reduce significantly.
- Natural lighting can have ancillary effects on energy efficiency. For example, you won’t need grow lights if you have indoor plants, and you’ll be able to use solar chargers for some gadgets. Designing one or more carrels where you have natural lighting will make this effortless.
- Natural lighting might enhance the aesthetics of your house, which with improved energy efficiency, can increase its value. Besides, you will use less non-renewable energy, and your home will have a lower carbon footprint.
Cons of Natural Lighting for Efficiency
The drawbacks of using natural light for enhanced energy efficiency in your house include the following:
- Optimizing natural lighting in a house can be expensive, especially if you don’t have anything to expedite the process. Everything from solar tubes to skylights costs substantial money. Therefore, a passive solar design is not a turnkey proposition.
- Natural lighting for efficiency might have limitations, particularly for houses without a suitable orientation to optimize daylighting or its effects. Also, not every region in the country receives adequate sunlight throughout the year.
- Natural lighting can adversely affect indoor fixtures and spaces, like deteriorating furniture and fading paint. You can prevent these problems with appropriately glazed windows and leveraging indirect natural light rather than direct sunlight.
- Overexposure to UV radiation might cause skin problems. This consideration applies to both direct and indirect natural lighting. Glass blocks UVB radiation, not UVA, so you will probably not have a sunburn. Still, you may be vulnerable to other skin conditions.
The incorrect use of natural lighting can reduce your home’s energy efficiency, so you need a practical and pragmatic plan—problems such as solar heat and UVA radiation are manageable because you can use low-emissivity glass. There are other coatings and varieties, too.
Natural lighting can help most homeowners improve their energy efficiency, regardless of climate. But you need a good strategy and flawless execution.
If you are interested in passive solar designs, check out our shortlist of seven sites to explore sustainable plans.
- University of Chicago: Le Corbusier
- University of Chicago: Louis Kahn
- United States Department of Energy: Daylighting
- Attainable Home: What Is Passive Solar Home Design – Should You Consider It?
- Attainable Home: Passive Solar Homes in Cold Climates (6 Design Examples)
- National Institute of Building Sciences: Daylighting
- Designing Buildings Ltd: Daylight Lighting Systems
- United States Energy Information System: How Is Electricity Used in U.S. Homes?
- Stanek Windows: What Is Low-E Glass & Does It Make Windows Energy Efficient?
- Attainable Home: Top 7 Sites To Get Your Passive Solar House Plans Today
- The Skin Cancer Foundation: 5 Sneaky Ways You’re Being Exposed to the Sun’s UV Rays
- The Skin Cancer Foundation: Healthy Skin – Made in the Shade?
- The University of Iowa Health Care: Skin Problems Due To Sun Exposure