Everything You Need to Sort Out Before Your Pergola Goes Up
pergola can completely transform how you use your outdoor space - turning a plain backyard into somewhere you genuinely want to spend time, whatever the weather. But the pergola itself is only part of the story. The preparation that happens before a single post goes into the ground has more influence on the final result than most people appreciate. Get it right and the whole project comes together smoothly, looks exactly as you imagined, and lasts the way it should. Skip the preparation and you're setting yourself up for complications that are far harder to fix once construction has started. Anyone who has looked seriously into building a pergola in Perth or anywhere else with a demanding outdoor climate will know that the groundwork - literally and figuratively - is where the project either sets itself up for success or stores up problems for later.
This article walks through the key preparation steps that make a pergola project go well: from planning permissions and site assessment through to ground preparation, services, and thinking carefully about how the structure will connect to your existing outdoor space. Some of it is practical groundwork. Some of it is decision-making. All of it matters.
Whether you're planning a freestanding pergola in the middle of the garden or an attached structure coming off the back of the house, the preparation principles are largely the same - though the specifics vary with site, size, and structure type.
Start With the Planning and Approvals Question
Before you do anything else, find out what approvals your pergola requires. This is the step most people want to skip, and it's the one that causes the most expensive problems when it's ignored. Pergola regulations vary considerably between local councils and jurisdictions - what qualifies as a permitted development in one area may require a formal building permit in another, and the rules typically depend on factors like the size of the structure, its height, how close it is to property boundaries, and whether it's attached to the house.
A quick call or online check with your local council will clarify what's required. If a building permit is needed, factor the application time into your project timeline - waiting until you're ready to build to discover you need a permit that takes several weeks to process is a frustrating and entirely avoidable delay. If you're in a heritage area or subject to a body corporate, there may be additional design or materials restrictions to navigate as well.
Getting approvals sorted at the very beginning of the project also means that your design decisions are made within the correct parameters from the start, rather than having to be revised later to comply with requirements you weren't aware of.
Assess the Site Properly Before You Commit to a Design
A thorough site assessment before finalising your pergola design is one of the most valuable things you can do. It sounds obvious, but many people design the pergola they want and then try to make the site fit, rather than letting the site inform the design. The result is often a structure that doesn't quite work - positioned where it catches the worst of the afternoon wind, shading areas of the garden that would have been better left open, or sitting awkwardly in relation to the house and existing landscaping.
Spend time in the space at different times of day and in different weather conditions. Where does the sun fall in the morning and evening? Where does shade naturally occur during the hottest part of the day? Which direction does the prevailing wind come from, and is there a position that would offer better natural shelter? How does the proposed pergola location relate to the view from inside the house - will it enhance or interrupt it?
The answers to these questions should meaningfully influence where the pergola goes, how it's oriented, and what kind of roofing or screening it has. A pergola that's positioned and designed with the specific conditions of the site in mind will be used and enjoyed far more than one that wasn't.
Check What's Underground
One of the most important pre-construction checks for any pergola project is locating underground services in the area where posts will be footed. Gas lines, water pipes, electrical conduits, and irrigation systems can all be present at depths that bring them into conflict with pergola footings - and striking one during excavation ranges from expensive and inconvenient to genuinely dangerous.
In most places there are free or low-cost services that can identify the location of underground utilities before excavation work begins. It's a straightforward step that takes very little time and eliminates a significant risk. Even if you're confident there are no services in the area, it's worth the check - services are sometimes installed in unexpected locations and are not always where plans suggest they should be.
If your garden has an irrigation system, mark out the location of all pipes and heads before construction begins so that the pergola footing positions can be confirmed as clear. Relocating an irrigation line before construction is a minor task; repairing one that's been severed by a post hole is more involved and disruptive.
Sort Out the Ground Surface Beneath the Pergola
The surface underneath the pergola is a decision that's much easier and cheaper to make before the structure goes up than after. Once the posts are in and the pergola is built, adding or significantly changing the paving or ground surface becomes more complicated and more expensive - you're working around posts and footings rather than having a clear, open area.
Think about how the pergola will be used and what surface suits that use. A dining or entertaining area calls for a hard, level surface - paving, concrete, or decking - that's practical underfoot, easy to clean, and suitable for furniture. A pergola used more as a garden feature or walkway might suit a gravel or decomposed granite surface, which is more relaxed in character and less expensive to install. Whatever you choose, the surface should be planned and ideally installed as part of the project rather than as a separate phase.
If the area beneath the pergola currently has lawn or garden beds, these need to be removed and the ground prepared properly before the surface goes down. Laying paving directly over lawn or loose topsoil produces an uneven surface that settles, shifts, and looks poor within a season or two.
Think About Drainage From the Start
Drainage is one of the most common afterthoughts in outdoor construction projects, and one of the most expensive problems to fix retrospectively. A pergola with a solid or semi-solid roof covering creates a surface that collects rain and needs somewhere to direct it. A paved area underneath the pergola needs to be graded correctly so that water runs off the surface and away from the house rather than pooling.
Before construction starts, consider where roof water from the pergola will go. Will you connect guttering to the house drainage system? Direct it to a water tank? Allow it to disperse across the garden via a channel drain at the edge of the paved area? Each option has implications for the construction details of the pergola and the surrounding hardscape, and these are much easier to build in from the start than to add later.
The grading of the paved surface also needs to be established during ground preparation, before paving goes down. A fall of around 1 in 60 - roughly 1.5 centimetres per metre - is generally sufficient to move water off a paved surface effectively without being noticeable underfoot.
Plan Your Electrical and Lighting Needs Early
A pergola with good lighting and, if relevant, power for an outdoor heater, ceiling fan, or speaker system is infinitely more usable than one without. But adding electrical services to a completed pergola is significantly more complex and expensive than incorporating them during construction - conduit needs to be run underground to the structure, and wiring needs to be concealed within the posts and beams rather than surface-mounted on a completed frame.
Think carefully before construction about what electrical capability the pergola will need, both now and in the foreseeable future. Even if you don't plan to install a ceiling fan immediately, running a conduit to the position where one might eventually go costs almost nothing during construction and saves a significant amount of disruption later. The same logic applies to outdoor power points and speaker wiring.
Lighting in particular deserves careful thought. The difference between a pergola that's pleasant in the evening and one that's genuinely atmospheric often comes down entirely to the lighting design. Get a sparky involved early in the project to discuss options and make sure the electrical rough-in is done correctly before the structure is finished.
Consider How the Pergola Connects to the Rest of the Garden
A pergola that sits in isolation from the rest of the garden tends to feel like it was added as an afterthought rather than designed as part of the space. The most successful pergola projects are ones where the structure feels integrated - where the materials, scale, and positioning relate thoughtfully to the house and the surrounding garden.
Before construction, think about how pathways, garden beds, lawn edges, and existing features will need to be adjusted or extended to accommodate the new structure. Will the pergola create a visual boundary that needs planting to soften it? Will the change in surface level require a step or a transition edge? Is there an existing tree or garden feature that needs to be relocated or removed before work starts?
These are not afterthoughts - they're part of the project. Addressing them before construction begins means the finished result looks considered and complete rather than like a structure that was dropped into the garden without thinking about what surrounds it.
Preparation Is Where the Project Is Really Won
It's easy to focus all your excitement and energy on the pergola itself - the design, the materials, the way it's going to look. And that's completely natural. But the quality of the preparation work that happens before construction is what determines whether that vision becomes reality without complications, delays, or costly surprises.
Approvals, site assessment, underground services, ground preparation, drainage, electrical planning, and integration with the broader garden - each of these is a piece of the puzzle that's much easier to address before the build than after. Treat the preparation phase as seriously as the construction phase and you'll end up with a pergola that performs as well as it looks.
Working with an experienced team from the planning stage through to completion makes all of this significantly more straightforward. Professionals who build a pergola regularly will anticipate the preparation requirements that first-timers don't know to think about - and that foresight is one of the most valuable things they bring to the project.
