Interior designers share 10 parts of their job you don't see on TV

• Interior designers told Insider some of the things they wish people knew about their jobs.
• This job isn't always as fun as it seems on TV, and it requires a lot of math skills.
• Many interior designers work on their own or as part of very small teams, so they have a lot of responsibilities that can range from installing light fixtures to cleaning a carpet.

A good interior designer can take a space from bland to beautiful, but there's more to this seemingly glamorous profession than what meets the eye.

Insider spoke to professional interior designers to discover what their jobs are really like, and what they wish potential clients knew before hiring them.

Read on to see what they said.

Not trusting your designer can make a project take longer and cost more

Interior designer Joe Human of Designs by Human told Insider that his biggest pet peeve is when clients don't trust their designer or try to do all of the work themselves.

"It's hard when clients start giving advice based on what they saw on HGTV or what their friend's designer did," said Human.

He said that interfering too much with a designer's process can end up unnecessarily prolonging a project.

"The projects where the clients trust you and collaborate with you turn out the best, and they always end up done on time and on budget," said Human.

It's surprisingly stressful to create gorgeous pillow combinations

Human said that the perfectly curated pillow arrangements you see online and in magazines take some serious time and effort to get just right.

"We can spend hours picking fabrics and swapping out pillows of different colors to make the perfect combination," he told Insider. "It looks effortless in the end, but we may have tried 25 different pillows to get that look."

Picking out materials and decor isn't as glamorous as it looks on TV

Many things look more fun on television, including shopping for design materials.

"On TV, the designer goes to one showroom and picks a tile and it's within budget and in stock," said Human. "In real life, that happens about 2% of the time."

He said that designers typically visit several showrooms, do research online, and lug around heavy containers of tile and fabric samples to showrooms in order to find a match.

"We then have to convince our clients to like the sample, and then we need to create drawings, rendering, and boards," he added.

Some designers use specific paint colors and patterns for psychological reasons

Interior designer Kimberly Horton of KH Home Design told Insider that designers often use certain colors and designs to "hack" human psychology.

"Different colors affect our brain and moods differently," said Horton. "Some colors, like red, can actually raise your blood pressure. Stripes can make a room seem longer or wider, depending on their orientation."

Many designers, for example, would use soothing colors like blue in a bedroom, rather than energizing colors like red or bright yellow.

It's unrealistic to expect your whole house to be redesigned in a month

Reality television makes it seem like a total house transformation can be accomplished in a single afternoon. In reality, large-scale projects can take months, not weeks.

"Completing a whole house design with renovations in mere weeks is very difficult," Horton told Insider. "It's an unrealistic expectation, and requires a large team of people and a lot of late hours."

Many designers work solo or with small teams

Some designers are very hands-on with their clients' spaces, which may include doing a lot of the dirty work themselves.

"We don't all come with a football-sized team of staff to get this work done. Some of us work in small teams and do a lot of the heavy lifting ourselves," said Horton.

Because of this, an interior designer's job can sometimes include working in a client's home to install fixtures, move furniture, and clean up after contractors.

Having a clear design vision can help a client save money

Beverly Solomon of Beverly Solomon Design told Insider that interior designers usually price their expertise by the hour. This means that a client who doesn't have a clear vision for their space may end up spending more money.

"When the client consumes more of our time ... especially by making changes once the project has already started, we need to charge them more," she explained.

To keep costs low, Solomon recommended doing your research and having a sense of what you want before approaching a designer.

"The more the client can give us a clear vision of what they want in terms of look, feel, function, and budget, the more money they will save," said Solomon.

The final cost of a design can vary wildly based on the materials clients select

If you believe every white kitchen tile costs roughly the same, you may want to think again.

Solomon explained that clients often don't appreciate how choosing one material over another can change the final cost of a project.

"It's frustrating when clients don't understand the huge variations in price due to quality, materials, skill of labor, name brands, and other factors," said Solomon.

One advantage of working with a designer is that they can help you select more affordable materials or items that closely mimic the look and quality of more expensive materials.

Designers love the big reveal, and sometimes it's the best part of their job

Interior designer Charmaine Wynter of Charmaine Wynter Interiors told Insider that her favorite part of the job is showing clients their newly designed spaces.

"After 26 years in the business, I still love seeing the look on my clients' faces when they realize that all of the stress and anxiety from the previous weeks and months was all worth it," said Wynter.

Designing a space requires some decent math skills

The job qualifications of an interior designer extend far beyond having pillow-fluffing skills and good taste in cabinetry.

Wynter told Insider that a good designer needs to know a lot about measurements and geometry.

"It would surprise most people to learn just how much math and science skills are needed to do this job," said Wynter. "Designers are constantly calculating square footage, yards, volume, and cubic feet."

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