There are certain recognizable stages of any significant renovation: the excitement. The planning. The budgeting. The trying to keep it on schedule. The flying of the dust. The anxiety about how it will turn out. The relief once it’s over.

Ashok Bajaj is almost always at some point of that process. His Knightsbridge Restaurant Group boasts eight restaurants in the District, including Bombay Club, Rasika and Oval Room, and when he’s not in the midst of physically transforming one of them, he’s probably thinking about the next project.

Restaurants, Bajaj said, “always need upgrading.”

Your living room may look the same as it did when you moved in a decade ago, but restaurants don’t have the luxury of, or interest in, waiting around until Pinterest inspiration strikes. Trends change, furnishings wear out, new restaurants open and put the pressure on existing ones.

Rather than an obligation, though, restaurateurs often see renovation as an opportunity.

“After eight years, we want to renew the energy,” said Scott Drewno, executive chef at the Source by Wolfgang Puck, which recently reopened in Penn Quarter after a month-long top-to-bottom overhaul. “You definitely want to do something to push yourself forward.”

Forward motion is something Robert Wiedmaier is always considering when it comes to Marcel’s, his fine-dining establishment that opened in 1998 in Foggy Bottom.

“You’ve got to be constantly changing,” the chef-owner said. “My philosophy is, change is good.” In fact, while he redid Marcel’s for a grand total of about $500,000 last year, he said he tends to make tweaks — in staff uniforms, candle holders, artwork, menus — on a rolling basis.

With any large renovation, there has to be a balance between the new and the familiar for diners, Wiedmaier said. So why go to the risk of upsetting the balance?

One reason: everyday wear and tear. “You have to factor in damage,” said Wiedmaier, motioning to the white leather seating he said is constantly at the mercy of the pens in patrons’ pockets. “The place is being used all day long.”

After Bourbon Steak had been open for eight years, the floor and seating in the lounge looked worn, said former general manager Mark Politzer, who has since moved on to a vice president-level job with the Mina Group, which owns the restaurant in Georgetown’s Four Seasons hotel. The solution: A $400,000 lounge redesign and dining room refresh.

The variability in materials and in restaurants in general means there’s no established standard for how often renovations happen, said Joe Spinelli, president of College Park-based Restaurant Consultants. For his part, Bajaj said he anticipates a seven- to-eight-year gap between makeovers.

A renovation, however, might address more than what a constant flow of diners can do to a restaurant: It might give them what they’ve been asking for.

Several components of the Source’s renovation were in response to customer requests, Drewno said. Those who inquired about a chef’s table will now have an opportunity to sit at a two-person counter overlooking the new lower-level kitchen. Patrons will be able to satisfy their interest in interactive dining at a four-person hot-pot table­ in the upstairs dining room, as well as with a soup cart that facilitates tableside preparation.

The Source’s renovation included several details suggested by diners. (Rey Lopez)

Last year’s renovations at Marcel’s cost about $500,000. (Scott Suchman/For The Washington Post)

At Rasika, the buzz about the food was nearly as strong as the commonly remarked-upon din in Bajaj’s Penn Quarter Indian restaurant. Installing a new acoustic ceiling was one motivation for the $400,000-plus renovation in July, which also allowed Bajaj to bring a “richer” feel with design touches such as silk wall coverings, gold artichoke-shaped lighting and Italian armchairs.

Bajaj went straight from the Rasika renovation into one just around the corner at 701, his 25-year-old contemporary American spot. There, too, Bajaj said, he sought to keep up with what customers wanted, particularly more space for private dining.

The Source, Marcel’s, 701 and Rasika all temporarily closed their doors to complete their renovations, and that in itself can create high — maybe unreasonably high — expectations from diners, said Spinelli.

“They’re thinking it of being a brand new place,” he said.

That can be exactly what restaurateurs are aiming for.

The goal at the Source was to make it seem “like a new restaurant,” Drewno said. At 701, the grand-reopening feel covered everything from carpeting and upholstery to staff uniforms and tableware. Additionally, both restaurants feature overhauled menus.

That sort of investment in a business can reinvigorate the staff, not just diners.

Ashok Bajaj recently renovated 701, his Penn Quarter restaurant that opened in 1990. (Greg Powers)

“I can honestly say from my point of view, it’s much more exciting to come to work in a fresh environment,” the Mina Group’s Politzer said.

“What it shows in the kitchen and dining room is you care to maintain the standards,” Bajaj said. That will make employees care, too, he said.

Putting money into a restaurant projects a sense of longevity, Wiedmaier said. He wanted his staff to know that he intends Marcel’s to stay, because “down the road, I’d like to see them take it on.” (Longevity isn’t always a given, however, when a restaurateur doesn’t own the space he or she occupies.)

With any renovation, there’s the risk that diners won’t like the results. Then again, Spinelli said, “Our business is built on risk.”

On the surface, a renovation doesn’t always make financial sense, especially because it won’t necessarily translate into additional sales.

In fact, it can dampen them in the short-term. “That’s two weeks of no revenue and spending money,” Wiedmaier said of Marcel’s 2014 closure.

But he and others said that if you go into a restaurant renovation thinking about what you’re going to get out of it money-wise, you’re probably thinking about it all wrong.

Despite the work, doing renovations is “a pleasure” to Bajaj. He likes to think that “we eat with all our senses,” which is one reason why he is so hands-on in the process, down to the artifacts he brought back from India to display in Rasika.

Once every detail has been put in place, all you can do is just step back and hope for the best.

Said the Source’s Drewno, “You want it to be perfect.”