Glenn Vanderhoof is vacationing in Hawai'i for nearly a month with just three changes of clothes.

The 38-year-old U.S. Air Force aircraft mechanic from England recently camped on the Big Island in his own tent for $10 a night, and pays $25 a night for a bunk bed at a Waikiki hostel. He dines on sandwiches and fruits from the ABC Store.

"Cheapest I can get, that's my budget," Vanderhoof said with a smile. With the cost of accommodations, food and "the occasional six-pack, you're talking about $50 a day. For this area, of course, that's very good."

In the midst of record-high hotel room rates, budget travelers like Vanderhoof have been finding a way to enjoy Hawai'i on far less than the $171-a-day that tourists spend on average. Through April of this year, statewide average daily rates for budget hotels — the cheapest category — have topped $100 a night, up from $71 for the same period last year, according to Hospitality Advisors LLC.

These travelers, often traveling with only their backpacks, appear to be largely under the radar of Hawai'i's $11 billion tourism industry, which primarily focuses on luring higher-spending visitors here.

Unlike the wealthier tourists the industry spends millions a year to attract, budget travelers mostly stay at hostels for a fraction of the price of a hotel room. They don't pamper themselves with massages and facials in posh day spas. They may stroll around Ala Moana Center, but they're more likely to spend their money at the Makai Market than Louis Vuitton.

There's little research about backpackers, including their spending habits. About 38,082 visitors stayed in hostels last year, up 6.9 percent from the year before, according to the state Department of Business, Economic Development and Tourism. But that's only 0.5 percent of the 7.46 million tourists who arrived in the Islands.

The 13 hostels in Hawai'i make up just 1 percent of the 1,266 accommodation properties in the state, according to state figures.

The Hawai'i Tourism Authority promotes Hawai'i as an active vacation spot for all travelers, but doesn't specifically target backpackers because "it's such a small segment of visitors to Hawai'i," said Rex Johnson, Hawai'i Tourism Authority president and CEO.

There's also limited hostels and camping grounds, said state tourism liaison Marsha Wienert.

Even so, Hawai'i still attracts backpackers, many of whom visit the Islands in between traveling to several other destinations, such as the Mainland, Asia, Fiji and Australia.

Olivia Harding and Emma Whittall, for example, recently left their advertising jobs in England to take a yearlong trip around the world. They arrived in Hawai'i after making several stops on the Mainland and planned to move on to Fiji, New Zealand, Australia and Thailand.

The 25-year-olds caught the bus and walked rather than renting a car and often cooked their own food in the Waikiki hostel they're staying in for $22.50 each a night. They estimated spending about $30 to $50 a day, including accommodations.

"There are a lot of attractions here that are free," said Whittall. Their plans included hiking up Diamond Head and snorkeling at Hanauma Bay.

Juha Ilander, a 38-year-old aircraft mechanic from Finland, was spending six days in Hawai'i as part of a two-month trip that included China, Thailand, Fiji and Australia. He planned to travel around the island by bus and go hiking, using recommendations from his Lonely Planet guidebook.

Ilander estimated spending about $50 a day here, including lodging, food and drinks. But travelers can spend even less in other destinations like Thailand, he said.

The Waikiki Beachside Hostel — which has 160 dorm beds and 13 semi-private rooms — has an occupancy in the 90 percent-plus range during the busy winter and summer seasons, said general manager Orlena Wong. Most of the travelers who stay there are between 18 and 35 years old, and the hostel is popular with people from Europe and New Zealand, she said.

Many hostel guests at the Backpackers Plantation Village on the North Shore are college-educated and in their 20s, said general manager Sharlyn Foo. But over the years the Plantation Village — which includes hostel beds and cabins and is popular with surfers in the winter — has hosted more people of all ages, she said.

"What I like is these people are so diverse, and some can definitely afford more and they choose not to because it's a fun way to travel," Foo said of the guests. "You can travel by yourself and yet not be by yourself."

Zena Alston left her job as an insurance underwriter in England just weeks ago and plans to travel around the world with her boyfriend until the end of September.

The 22-year-old, like many other backpackers, was interested in learning about Hawai'i's culture. But she was disappointed.

Waikiki, she said, has been "ruined."

"I think it would be a beautiful island, but having McDonald's and Starbucks on the seafront isn't quite right," she said. "It's very commercialized. There's no culture. It seems to have been trodden all over by America. You don't learn anything about the history of Hawai'i."

Alston planned to cut her O'ahu trip a few days short to 15 days, in part because of the cost and also because "I've done everything" here. She doesn't recommend traveling to Hawai'i on a tight budget.

"I'd probably say wait until you have the money to really enjoy it," she said. "I don't think this is a backpacker's place. I think this is a holiday place, where you come for a week and blow your budget."

Reach Lynda Arakawa at larakawa@honoluluadvertiser.com.