Courtesy Kevin Steele/Playa Viva
Modern tree houses blend luxury with sustainability in order to fit within their natural environments. This cylindrical tree house at Playa Viva in Juluchuca, Mexico is built with sustainable bamboo.
LeonardoPalafox/Playa Viva
The tree house suite is ocean-facing and surrounded by palm trees. Playa Viva markets itself as a resort "Where your vacation meets your values".
Courtesy Blue Forest Luxury Tree Houses
Combining organic and contemporary lines, the "Fibonacci Tree House" is inspired by the geometry of the 'Fibonacci Spiral" often found in nature.
Courtesy James Lozeau/Finca Bellavista
This sustainable tree house community in the Costa Rican rainforest is completely off the grid. Nearly 50 tree houses are connected by ziplines and suspension bridges.
Courtesy Blue Forest Luxury Tree Houses
"The Treehouse Kitchen", located in Surrey, England, is a function venue for a gourmet meal company, as well as being a private retreat.
RagnarThSigurdsson/Arctic Images/Treehotel
"The Cabin", a prefabricated tree house in northern Sweden, is so high up in the trees that it overlooks the entire Lule River valley.
Courtesy Saraii Pvt Limited
Saraai Village is an eco-tourism resort in the South of Sri Lanka built from recycled and up-cycled materials.
Courtesy Saraii Pvt Limited
The tree house platforms are discarded railroad ties, and the beds and furniture are made out of discarded electricity poles from Sri Lanka.
Courtesy Matt Livey/Blue Forest Luxury Tree Houses
Classic oak flooring and cedar lining give off a lovely wooden scent within this private hideaway designed by Blue Forest. "The Nook" tree house blends with the undergrowth and surroundings.
Courtesy Blue Forest Luxury Tree Houses
As if by magic, "A Fairytale Castle" has been constructed around a tree, with smaller trees branching up through the decking.
Courtesy Blue Forest Luxury Tree Houses
A rope bridge stretches from this "Cliffside Lodge" tree house to its owner's thatched home. The tree house features western red cedar and recessed halogen lighting.
Courtesy Treehotel
The seven tree houses at the Treehotel in northern Sweden all sport imaginative, eco-conscious designs.
Courtesy Treehotel
While "The Dragonfly" is built out of wood, its exterior is made out of sheet metal that will, over time, turn rust-brown and blend in even further with the pine forest.
Courtesy Treehotel
From the outside "The Bird's Nest" camoflages with its surroundings and looks exactly like a gigantic bird's nest. The interior, however, is a spacious environment big enough for a whole family.
Courtest Treehotel
The mirrored walls of this Treehotel were designed to reflect the pristine surroundings. The base consists of an aluminum frame around the tree trunk and the interior is made from plywood with a birch surface.
Courtesy Blue Forest Luxury Tree Houses
In this tree house the walls are fixed with hand-split oak shingles and cedar tongue-and-groove boards, and the trunk of the host tree rises up through the middle.
Courtesy Blue Forest Luxury Tree Houses
The "ecoPerch" is made with sustainable construction materials throughout and is designed to mesh with the surrounding environment.
Courtesy Blue Forest Luxury Tree Houses
While the Treehouse kitchen was built for "big kids", there is a special platform off the main structure with zip wire and rope bridges for real kids to play on.
Alex Whittle/Blue Forest Luxury Tree Houses
This two-level timber hideaway is nestled within the branches of a mature oak tree.
Alex Whittle/Blue Forest Luxury Tree Houses
"Timbertop Hangout Treehouse" is fitted with a crow's nest lookout raised high above, and a stainless steel slide.
Courtesy Blue Forest Luxury Tree Houses
"The Magic Home" features a secret revolving bookcase which reveals a spiral staircase leading up to a playroom for the kids.
Matt Livey/Blue Forest Luxury Tree Houses
"Little Acorn Treehouse" is nestled among the boughs of an enormous oak tree. The tree house was designed in natural tones to mimic the earth, tree trunk and leaves of the host tree.
CNN  — 

Many a child spent their youth scrambling up trees and building secret dens in the branches.

In an instant, plain-planked interiors propped in the trees transformed into faraway lands, forts and hideaways.

Brothers Andy and Simon Payne were no different. Growing up in Kenya, the two spent a great deal of time constructing zip wires, jungle swings and rudimentary tree-top homes.

But the Paynes never gave up on their childhood dreams of building elaborate houses in the trees, and have continued to design and build impressive, eco-friendly tree houses for the young at heart.

“A big part of the emotional reason why people decide to build a tree house is because they remember fondly the fun they had as kids,” Simon Payne tells CNN.

They now head the world’s leading tree house company, Blue Forest, named after the blueish hue of the distant pine forests in a mountainous region of Japan and born from a desire to bring people closer to nature.

Reflecting the environment

Blue Forest has built hundreds of tree houses which reflect the environment in which they rise through the use of sustainable construction materials such as timber.

“I think people love tree houses because of the warmth of timber, when you walk into the tree house you get this lovely woody smell.”

Alex Whittle/Blue Forest Luxury Tree Houses
Blue Forest's Timbertop Hangout Treehouse

The company works alongside the world’s largest forest certification system, PEFC, to ensure that its wood comes from sustainably managed land.

“You can find out exactly where the tree was grown, when it was cut down and how many trees were planted to replace it,” says Payne.

Blue Forest also encourages clients to build with high levels of insulation and use renewable energy.

However, it’s not easy for tree houses to be completely off the grid, and, according to Payne, the elements that make the tree houses the most sustainable are often the simplest.

“Although everyone in truth wants to hear about renewable energy solutions and all of that, actually insulating your building really well, using the natural resources of the sun and the wind for cooling and heating, using simple things like low-energy lighting, they probably make the biggest difference.”

Going off the grid

Courtesy James Lozeau/Finca Bellavista
In setting out to save a chunk of the rainforest, Matt Hogan and Erica Elise Andrews formed Finca Bellavista -- a tree house community in Costa Rica.
Courtesy Matt Berglund/Finca Bellavista
"People are drawn to the simplicity and the purity of living in such a pristine and beautiful area," Matt Hogan tells CNN.
Courtesy James Lozeau/Finca Bellavista
"I used to commute two hours each way in and out of the city in Baltimore and wear a suit everyday and that was very telling as to why I now live in the middle of the rainforest because it drove me crazy," says Hogan. Pictured here, Erica and Matt take a break from ziplining in the rainforest.
Courtesy Matt Berglund/Finca Bellavista
Now, Matt compares life in the rainforest to "living in one of those spa CDs of rainforest sounds". "It's like this sensory overload experience," he says.
Courtesy Matt Berglund/Finca Bellavista
"You're completely immersed in nature -- you go to bed listening to the bugs and the frogs and you wake up with bird song."
Courtesy Matt Berglund/Finca Bellavista
In just over ten years, the community has planted several tens of thousands of trees to regenerate the rainforest.
Courtesy Matt Berglund/Finca Bellavista
Finca Bellavista is a pedestrian community connected by hiking trails, ziplines and suspension bridges.
Courtesy Matt Berglund/Finca Bellavista
The community grows up to 80% of its food on site, and is completely off the grid in terms of power production, opting instead for solar power.
Courtesy James Lozeau/Finca Bellavista
Treetop homes are constructed using bamboo and locally-grown teak, and for every tree that is cut down, many more are planted.

On the other end of the spectrum, deep in the Costa Rican rainforest, lies Finca Bellavista – a community suspended in the trees.

The 600-acre plot is home to approximately 40 treetop homes, where everything is solar-powered and “waste” is non-existent.

When Matt Hogan and Erica Elise Andrews first stumbled upon this little slice of paradise in the south Pacific coastal region ten years ago, it was on the brink of being carved into a timber harvest site.

Compelled to save this chunk of rainforest, the duo slowly began to regenerate the rainforest and build a life for themselves in the trees.

“Effectively, we try to design around the natural environment, we don’t allow people to cut down trees to build their homes,” Hogan tells CNN.

Similarly, community members are encouraged to source locally grown teak or other tropical hardwoods to build their tree houses.

Homes are stilt-built around the trees or make use of hybrid designs so that the bulk of the house is supported by posts and the trees used as anchors.

There are also fully arboreal houses built in long-living, deep-rooted trees deemed suitable by an on-site botanist.

One such tree is El Castillo Mastate – a tree house suspended 90 feet off the ground. “It’s kind of the Taj Mahal of tree houses that we’ve built,” says Hogan.

Courtesy Matt Berglund/FincaBellavista
El Castillo Mastate in all its glory

Finca Bellavista is a pedestrian community, which means tree houses are accessible via zip lines, suspension bridges and 11 kilometers of hiking trails.

All water comes from gravity-fed hand-dug springs on the property. Every house is also required to have a biodigester to break down all the black water human waste.

In addition to this, there is a grey water management for the showers and sinks and a redworm compost system.

“All of it is very connected and we produce very little trash,” explains Hogan. “We recycle and utilize everything the best we can.”

Living the high life

Most homeowners retire to Finca Bellavista for a few weeks or months a year. The rest of the time their homes are rented out.

“It’s a very attractive thing for a lot of people, whether it’s for a vacation or a life change and I’d say that most of the people that ended up buying properties have done so because of the connection they have with nature,” says Hogan.

“You’re completely immersed in nature, you go to bed listening to the bugs and the frogs and you wake up with bird song,” he explains. “It’s kind of like living in one of those spa CDs of rainforest sounds.”

Blue Forest also find their clients are looking to reconnect with nature. It is this love of nature that makes sustainability a top priority – if not something of a luxury – in the tree house business.

Courtesy Blue Forest Luxury Tree Houses
Fibonacci Tree House designed and built by Blue Forest

According to Payne, high-end clients who prefer hardwood are often happy to pay a bit more for a sustainable alternative called Kebony.

Kebony uses a bio-based liquid to permanently enhance sustainable softwood, giving it premium hardwood characteristics and a dark brown finish.

“This Norwegian company has developed a really unique method for modifying what is just pine, a fast-growing sustainable species, and giving it the same characteristics as teak,” he explains.

Not-so sustainable?

It’s not always easy to meet a client’s needs in the most sustainable way possible.

“The hardest thing is when people want stone finishes,” says Payne. “We use higher-end suppliers, we don’t buy the kind of cheapest materials which end up coming from China and places like that and are probably not very sustainable.”

Similarly, Hogan explains how homeowners are starting to build with steel as it lasts longer than wood.

“There are some people that don’t necessarily trust the long-term viability of certain types of wood in our very challenging environment,” he says.

Payne adds: “We kind of do the bit we can on every job, and then certain jobs are just more sustainable than others, that’s the truth.”