Balloons will always be a signifier of single-digit birthday parties, a playful tool for sculpting hair with static.

But thanks to social media, balloons now lend a posh, arty aesthetic to event decor, in addition to their classic, if slightly cheesy, cheerfulness.

Inflatable arrangements once simply arched over doorways at pep rallies and proms, or formed Santas and toy soldiers at holiday displays. Today they cluster into garlands or cover ceilings in “clouds” at galleries and stadiums, weddings and galas, from Lincoln Center to the Calhoun Beach Club.

Giant strands of clustered balloons, often in various colors and sizes, snake across walls or along entryways. These air-filled festoons — décor’s version of the statement necklace — add visual pop and celebratory swagger. And compared with many large-scale decorating options, they offer a lot of bang for the buck.

Like the cupcake before it, the balloon is a once-mundane party staple reinvented for the Pinterest and Instagram crowd. With the aid of digital influencers, its popularity is soaring.

When it comes to complex balloon installations, Carly Van Veldhuizen, head of Minneapolis-based Girl Friday Creative, is the go-to gal in the Twin Cities.

On a recent morning, Van Veldhuizen and her crew of four constructed a massive blue balloon garland at the University of Minnesota’s McNamara Alumni Center.

A four-nozzle balloon filler emitted a rush of air and a high-pitched whine as the Girl Friday crew filled the balloons, hand-tied them, and threaded them onto the growing garland.

Van Veldhuizen’s company is known for designing and fabricating one-of-a-kind installations for events, using unconventional materials such as coffee filters, recycled plastic straws or string. It created its first balloon installation about two years ago, at the behest of the Knot magazine. Its clients now include Target, Mall of America, Starkey Foundation and the Vikings. More than a third of their jobs involve balloons, Van Veldhuizen said.

For the opening of Studio 125, a Minneapolis event space co-owned by Bridget Borden and Kate Arends, of the lifestyle blog Wit & Delight, Girl Friday created a white balloon installation to showcase the space’s natural light and airy feel. “It elevated the entire event,” Borden said.

Growing up, blowing up

Balloons themselves have changed. No longer just primary-colored orbs, they’re ombre-hued and hand-painted, shaped like unicorns and emoji. Shiny mylar balloons come formed as numbers, letters, and whole words in script, in trendy rose gold shades. Personalized balloons can be printed with uploaded photos. Confetti balloons explode colorful bits, at seven bucks a pop.

And while installations like the one at the McNamara Center can be complicated and expensive, more price-sensitive balloon enthusiasts can find DIY kits and online tutorials.

Christina Ries, a blogger for Minnesota Parent, created her first balloon garland for her young son’s birthday party this spring.

Inspired by writer/podcaster Nora McInerny (whose Instagram photos of her wedding included a balloon installation by Girl Friday), Ries spent about $40 on balloons and an electric air pump and strung together a wall-size garland in less than an hour. She’s since created three or four more.

“They’re all the rage, so I just couldn’t resist trying my hand at it,” Ries said. “I was pleasantly surprised it was so easy to do. Now my little homespun version of the balloon garland is my favorite go-to birthday party décor.”

It’s complicated

Girl Friday installations, on the other hand, can take the crew hours, as they work around sprinkler systems, dodge electrified pigeon wire and operate scissor lifts. Weather can also present a challenge. Balloons, they’ve discovered, can withstand temperatures from below zero to 100, but heat and heat combined with humidity can wreck havoc, as can static electricity and wind.

Custom installations requiring a couple thousand balloons (their largest used 50,000) start at $1,500, and the average client spends between $3,000 to $7,000.

Van Veldhuizen says she enjoys the challenge of engineering the installations, testing several materials and techniques in advance, as well as calculating forces and quantities. One challenge she hasn’t yet solved to her satisfaction is making event décor less wasteful and frivolous.

Girl Friday doesn’t work with helium or do balloon releases, due to concerns about harming animals and the environment. At the end of a typical event, they pop the arrangements — it usually takes about 20 minutes — and funnel the pieces into one bag.

“There’s less of a footprint than people think,” Van Veldhuizen noted.

Girl Friday has donated leftover balloons by giving them to nursing homes, but it’s a challenge to find the time and transportation to recycle arrangements.

Still, Van Veldhuizen hopes to share the joy of experiencing the balloon installations more widely. They give you the opportunity “of being outside of yourself for a moment,” she said, “and feeling like you’ve been transported.”