How to build a backyard treehouse

Kids in treehouse

Blanche Clark

Posted April 06, 2021

A treehouse is a great place for a child’s imagination to run wild, as long as it’s built with their safety in mind.

Best-selling children’s author Andy Griffiths has fond memories of afternoons at his cousin Dave’s place “lost in imaginative play” on a single platform in an oak tree. 

From that simple memory Andy has gone on to create the bestselling Treehouse series for children, fuelling their imaginations with crazy antics such as money-making machines, flesh-eating piranhas and exploding eyeballs. “Even just the idea of a treehouse is exciting – perhaps there’s an inner monkey in all of us just aching to get out,” Andy says. 

If you have a child who has read the Treehouse books and now wants a treehouse in your backyard, RACV trade training manager Andy Anderson says there are building and safety issues to consider first. He says building a treehouse presents more challenges than a standalone cubby house, and the design will depend on the tree.  

“The mistake is to attach the structure to both the ground and the tree. That is a recipe for disaster,” he says. “Trees and the earth naturally move away from each other and wind and tree growth will end up tearing the treehouse apart.”  

He suggests doing your research, keeping the design simple and consulting a carpenter or handyman with building experience if you’re unsure. “As adults, we tend to overdo things because we want it to look impressive, whereas as a kid, just being a metre off the ground is a big thing.” 

Five things you need to know about building a treehouse

Safety first

Build the treehouse low to the ground and away from power lines. The Royal Children’s Hospital’s Kids Health Information fact sheet on backyard and playground safety advises a maximum height of 2.5 metres and that anything over 1.5 metres high is not suitable for children under five years of age. 

Make sure the ground underneath the treehouse is safe and cleared of debris. Don’t build a treehouse over a concrete path or driveway.

Kids Health Information recommends an impact-absorbing surface under any climbing equipment, including treehouses, and a depth of at least 300 millimetres if you use woodchips.

Choose the right tree

Melbourne arborist Mark Haywood recommends consulting an expert to check the health and structure of the tree. “Sometimes you get forks in the tree, which might look great for a treehouse, but it’s actually a weakness in the tree, which can lead to a branch snapping off in a storm,” he says.

Mark, who owns Arborise Tree Care, says avoid digging around the roots because that can make the tree unstable. “If you are going to build a platform, don’t put too many nails or bolts in the same area or you could cause the equivalent of ring-barking and kill the tree,” he says. He also suggests making sure the tree is free of pests, including bee and wasp nests, and thorns.

Get your kids involved in the project. Photo: Getty
Check your neighbours are comfortable with your plans. Photo: Getty

Check with neighbours and council

Depending on the height of your treehouse, it’s prudent to check your neighbours are comfortable with your plans, especially if the treehouse overlooks their property. It’s also wise to discuss your plans with your local council first. 

In 2007, the Victorian government amended all planning schemes in Victoria to exempt cubby houses from planning-permit requirements, but treehouses were not specifically mentioned. Port Phillip Council, for example, says if a treehouse is located on private land and is less than 2.4 metres high and less than 10 metres square, it would not normally require a building permit. 

But Port Phillip Mayor Louise Crawford notes that under a community amenity law a permit is required to “destroy, damage or remove” a “significant tree”. “Depending on the size of the treehouse, it is likely residents would select a ‘significant’ tree to support the structure and as such, building and/or installing a treehouse would be considered damaging the tree,” she says. “We would encourage anyone intending to build a treehouse to speak to council so we can assist them with their project.”

Choose the right materials

RACV’s Andy Anderson says outdoor timbers, such as treated pine, should be used when building a treehouse, and screws or bolts rather than nails. “Nails should never be used to hold things together. A tree that moves constantly will pull those nails out in no time. A screw or a bolt has a lot more strength.”

You should make sure it’s easy and safe for children to get into the treehouse. Andy suggests either a rope ladder or steps that are screwed to the trunk rather than attached to the ground.

Involve your child 

Andy says the greatest value in building a treehouse will come from involving your child in the project. “It’s a chance to spend time with them. Let them contribute to the design and then enjoy the satisfaction of spending a day or so together building the structure.”

The Complete Guide to Treehouses (Black & Decker): Design & Build Your Kids a Treehouse, is available through online bookstores.