Building Near Trees? Read This First

If you're renovating, extending, or planning a new house, beware the tree regulations that could stand in your way

Rebecca NaughtinNovember 5, 2016

Well before graduating, Naughtin had already experienced the realities of working in an architectural office, initially working with architect Ivan Rijavec and then following in the studio of Harmer Architecture. Although computers are now at the forefront of architecture, Naughtin was part of a team which was keen to engage with the latest technology. The Spatial Information Architecture Laboratory, headed by Professor Mark Burry at RMIT and responsible for the restoration of Antonio Gaudi’s Sagrada Familia in Barcelona, formed an important part of Naughtin’s architectural trajectory. “We also worked with Frank Ghery’s studio and MIT. During that period I would have travelled at least half a dozen times to the United States and to Europe.” A trip with Professor Shane Murray, now dean of architecture at Monash University, was a study tour with leading cultural tour company Australians Studying Abroad (ASA). “At that point, I started to become more discerning, perhaps more critical of what I saw, seeing things more objectively.” So when Naughtin graduated from RMIT University with a first class honours, she was both more than capable and confident of taking up a full-time position with Bruce Allen Architects, suitably located at Stanhill, designed by architect Sir Roy Grounds. And with experience, as well as a desire to be more involved in the design process, Naughtin decided to form her own practice, Rebecca Nuagtin Architects (RNA) four years later in 2012. Although her administrative skills were sharpened and put to good use with her colleague architect Bruce Allen, she was keen to develop relationships with clients. “I would like to say that I have a good sense of humour, something that I think is important when you’re an architect. But that’s not to say that I don’t take my work and each client very seriously. It’s also important in my profession to be transparent,” says Naughtin. Another skill identified by Naughtin as being important is the ability to foresee issues or problems well before they arise, whether these be design-related, structural or cost-related. Naughtin also has the ability to ‘read’ clients, understanding what they are really hoping to achieve, as opposed to what they may initially present as being important to them, or alternatively something seen in a magazine or on television. “Delivering an endless wish-list is all doable. But it’s not something that will sustain a relationship or deliver the most appropriate outcome.” Naughtin and her team have built up a reputation for the residential work they have produced in the years since RNA was established. Capable of handling larger projects, be they commercial, institutional or educational, Naughtin sees the importance of starting with domestic work. “A house gives you the opportunity to solve the minutest problems. It’s an extremely complex area that takes time and enormous emotional commitment, for both client and architect. But it’s the satisfaction that it brings, when you know that every possible issue has been addressed and the client knows they have been given much more than was initially expected,” adds Naughtin. Text by Stephen Crafti

Trees can easily be overlooked during the design process, but they can become critical items later on. And don’t think you’re off the hook if you’re not planning to remove any trees to make way for your extension, renovation or new build. Building anywhere near a tree of significance (even if it’s not on your land) can bring with it regulations that might force you to change your design or limit your ability to build at all. It’s best to know where you stand with trees on or near your property early, before the design process gets underway – it will save you from headaches later.

Halo Interior Design

Do your homework early
Before you get started on planning your new or renovated home, call up your local council and ask about their tree protection policies or ‘Tree Protection Local Laws’. This will inform you of all the different aspects of dealing with trees within or near your site. Sometimes these documents can be a little user unfriendly, however, so let’s have a look into some of the key elements.

Box™ Design & Build

Name that tree
The first step is to identify what kinds of trees you have, especially those standing in the way of your proposed home or extension. This is typically required to be the botanical name of the tree, written in italics (Angophora costata, for example). There are many great books, apps and tree databases available that can help you identify trees. Hiring an arborist is a sure way to guarantee you’ve identified a tree in question by the correct name.

Fredrick Dawson Design Consulting

Assess its significance
Once you have identified the species of the tree, you then need to determine if the tree is a ‘significant’ or a ‘canopy’ tree. Different councils will have different requirements and definitions of what these entail, so it is best to check before making the assessment.

Significant trees can often be listed on a register available through the council. These trees have a top priority to be retained and having them on your property or on your neighbour’s can impact your design drastically if you are planning to build too close to them.

Baldridge Architects

Canopy trees can often be determined through measurements outlined by the council. The measurement of the trunk is typically taken from the DBH (diameter at breast height), which can be anywhere between 1.3 and 1.5 metres in height, depending on which council area you live in. You will then need to take the circumference you’ve gotten with the tape measure and convert it to a diameter. With this measurement you should be able to determine whether your tree is a canopy tree.

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C.O.S Design

The root of the issue
If your tree is determined to be either a ‘significant’ or ‘canopy’ tree and you are planning on building anywhere near it, you’d be better off to consult an arborist about your options for moving forward.

Restructure Studio

The arborist will determine the structural root zone, tree protection zone and crown drip line. They will then need to determine whether these will be accurate to your specific case. This is because these zones are determined through industry-standard formulas and can’t take into account conditions specific to your property.

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Strachan Group Architects

Some of the most important factors determining the assessment will be:

What species is the tree?
How does it react to various environmental conditions?
Does it have far-spreading roots?
Is it tolerant of heavy pruning?
Does it react well to compaction or water logging?

Then there are the site-specific conditions:

Are certain areas around the tree compacted, paved or impermeable?
Are there water sources nearby that would have attracted the root system to an area not near your proposed building?

These are all conditions that could affect what your tree protection zone and structural root zone actually are.

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Inspect and measure
Once again, an arborist will need to determine the relevant conditions and tree species attributes and then prove them to the council, ensuring the tree will not be damaged or distressed by your proposal. One technique to determine exactly where the roots are is through ‘air spading’. This involves excavation of the soil through a specially designed air-pressured hose, helping to prevent damage to existing roots.

Your arborist will then document the extent and health of the roots and may even invite a council arborist to come and inspect the tree themselves. More traditional methods of excavation, such as using a spade, crowbar or trenching, can severely damage roots and cause damage to the tree.

Black Bear Builders, Inc.

Infrared or thermal imaging technologies can also be used without damage to existing roots, though the accuracy of these can been questionable and the cost quite expensive. This is all dependent on which operator and equipment is used.

Kenneth M Wyner Photography Inc

Live and let live
Finally, if it is determined that your proposal does fall within the tree protection zone, a tree protection plan will need to be established outlining how your design is going to minimise any disturbance to the subject tree. This could be though certain construction techniques, management of the site during construction, cantilevering structures, permeable surfaces and so on. A joint discussion with your arborist, architect and builder will determine the best outcome for your design.

Tree in your way? Don’t cut It down just yet

Arkin Tilt Architects

If you absolutely want to ensure that your tree is not damaged during the construction process, bonds can in fact be placed on trees and are in some cases required by councils. This is a way to ensure that no damage occurs to your trees. In all cases it is best to consult experts in the field when dealing with trees in or around your property to ensure you, your architect, arborist and builder all have the same intentions of retaining your trees and potentially incorporating them into the design process.

YOUR SAY
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