The 7 Basic Principles of Interior Design

~ 8 minutes to read

When it comes to interior design, there are certain principles and elements that every professional needs to be aware of to create a cohesive and stylish space. By understanding these key concepts, they will be able to put together a functional and visually appealing room.

As professional interior designers in Miami, we approach the principles and elements of design with a unique perspective. We understand the importance of functionality and aesthetics in equal measure and strive to create beautiful and practical spaces. To us, every detail matters – from the color palette to the furniture layout.

Our goal is always to create interiors that reflect our clients’ individual styles and meet their specific needs. We take the time to get to know our clients so that we can better understand their vision for their homes. Then, we use our expertise to bring that vision to life.

Classy, elegant and modern living room

What are the principles of interior design?

The principles of interior design are the rules and guidelines that designers follow to create functional, aesthetically pleasing spaces. There are seven main principles of interior design: balance, harmony, rhythm, proportion and scale, emphasis, contrast, and details. These concepts can be applied to any room in your home, from the living room to the bathroom.

1. Balance

In design, balance gives the impression of equilibrium. It refers to a visual aspect, and it is about distributing furniture and decorative objects as evenly as possible so that things have the same visual weight when looking at a room. To achieve balance, it is important to pay attention to where the elements are placed within the space. For this, we must carefully analyze the line, shape, color, and texture of the different objects.

There are three types of balance: formal, informal, and radial.

Symmetrical or formal

Traditional or formal rooms require symmetrical balance, which is the art of mirroring and matching each side of a room. For example, two chairs on either side of a coffee table may be described as symmetrically balanced. This type of balance is simple to achieve since design features are duplicated on both sides. This technique is also known as the mirror effect. If you’re not careful, formal balance might quickly become boring and repetitive.

Contemporary elegant living room

Asymmetrical or Informal

The visual weights of lines, colors, forms, and textures are balanced without requiring exact duplication. This type of balance is not as ordered as symmetrical balance and can be more complex and exciting. For instance, a sofa can be balanced by placing two chairs on the other side.

an industrial styled living room

Radial balance

Radial balance is achieved when there is a central focal point with other elements radiating from or around it. An example would be a round dining table, with chairs arranged around it. There is a lot of repetition of form, texture, and color.

Contemporary dining room

2. Unity and Harmony

Unity is a significant feature of house design. Every furnishing, style, and decoration item must work together to create a cohesive whole. The combined cohesion and uniformity of all the design elements give your interior design its beauty. You must constantly remember that patterns, hues, texture, and so on should have a smooth flow throughout the project. Otherwise, the individual items in the space will clash and look out of place.

The principle of harmony is coordinating objects and colors in a space to convey a sense of integrated design. There is harmony when all the things in a room collaborate around a theme or style. Harmony can be created using various methods, such as grouping furniture together, using similar colors and textures, or making a focal point. When harmony is used in interior design, it results in a cohesive and inviting space. The key to creating harmony is to find the right balance of all the elements.

Dining room with wooden floor

3. Rhythm

If we were to analyze a piece of music, we would describe its rhythmic pattern. The same concept applies to interior design–we create rhythm through the visual repetition of form. When decorating our homes, we should think about arranging elements in a way there is repetition, progression, transition, or contrast. By applying these visual mechanisms, we can direct someone’s attention around the space and ultimately enhance the overall impression of the room.

Contemporary elegant white living room

4. Proportion and Scale

The concept of proportion and scale is the ideal approach to generate a sense of belonging among objects in a room. Things must be in balance with each other and the space, whether it’s size, shape, form, or color. The importance of this principle is understanding how to use the surrounding area, whether it be a large or small room.

Proportion is the relationship between two items, and scale is the way that one object’s size relates to another. For example, a huge, overstuffed sectional in a tiny space will be out of proportion. A small coffee table in front of two enormous sofas might appear misplaced and lost. 

The Greek ancients discovered the secret to proportions – The Golden Ratio. This formula makes all proportions more pleasing by reducing them to a simple equation: the perfectly symmetrical relationship between two proportions. This proportion is found in nature and is frequently used by artists and architects.

Creating visual interest in a room can be as easy as playing with scale. Scale refers to the relationship between the size of objects and the size of a space. To add excitement without going overboard, try combining ordinary items with pieces of different heights and dimensions, such as art or greenery.

Big living room with huge windows, stairs and a dog

5. Emphasis

In interior design, emphasis is the use of an accent in the room, such as color, component, texture, or pattern, that draws attention. A room with no focal point is forgettable and dull. The principle of emphasis, then, calls for choosing one item in the room to serve as the center of attention, around which the rest of the decor will revolve. Radial balance works with this principle and helps draw attention to the chosen point of emphasis in the room.

The focal point can be an existing feature you want to highlight, such as a fireplace, a piece of furniture, or art that you want to use as the starting point for your design. Once you have decided on your focal point, the rest of the room should be designed to complement it. Color is one of the most powerful tools that you can use to create emphasis. A bold color will immediately draw the eye, so if you want to highlight a particular area, painting it in an intense color is an effective way to do this. A pattern can also create emphasis; a bold pattern will make a strong statement, while a more subtle one will add interest without being overwhelming.

Texture is another tool that can be used to create emphasis. A rough texture will stand out more than a smooth one. So, if you want to highlight a particular area, using a textured finish such as stucco or brick can be an effective way to do so.

The principle of emphasis can be used in both small and large spaces. In a small room, it is often necessary to have a focal point to make the area feel more cohesive and unified. In a larger room, you may have more freedom to play with different elements and create multiple points of interest. However, too many focal points can be distracting and make the space feel cluttered. When using the principle of emphasis, it is essential to strike a balance between creating a space that is interesting and one that is harmonious.

Classic custom buiilt living room

6. Contrast

There are many ways to create contrast in a room. One of the most obvious is using color. Pairing light and dark or warm and cool colors can create a striking effect. You can also use contrast in terms of texture, pattern, and scale.

When using contrast in your design, it is important to remember that less is usually more. Too much contrast can be overwhelming and make a space feel chaotic. It is essential to find the right balance to create a pleasing and harmonious space. 

Contrast provides visual interest and helps to define spaces. Done well, it can make a room feel dynamic and exciting.

Now that you know a little bit more about contrast, look around your home and see where you can add a little bit of contrast to create visual interest. A few well-placed accent pieces can make all the difference in the feel of a room. So, get creative and have fun with it!

Dramatic black and white bedroom

7. Details

Attention to detail is the last of the basic principles of interior design. A room can never feel put-together and personal unless it contains the right finishing touches. And the good news is that you don’t need to be a professional interior designer to add them! This final step allows you to show off your unique style and personalize the space with things that interest you.

Details make a room unique. By adding personal touches and paying attention to small details, you can create a space that is truly your own.

Very bright and white living room with big windows

Thank you for reading!

Let us help you create your personal sanctuary. After all, you deserve the very best.

Kathryn Interiors is an Award-Winning, Full-Service Interior Design Studio in Miami


Picture of Hi, I'm Kathy!

Hi, I'm Kathy!

I am an expert color consultant with over 30 years of experience in interior and fashion design. I help both residential and commercial clients create unique looks for their homes and businesses.
Clients often come to me seeking sharp attention to detail, reliable work, and an excellent sense of design--all of which I pride myself on delivering.

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