Choose a pergola size by testing the usable layout beneath it. Measure your furniture, show how people move around it and place the posts from the exact product drawing. A larger roof area is not automatically a better fit if a post interrupts the main route or the structure crowds the house.
Measure three different things
Keep the available site, the structure's overall dimensions and the clear space between posts separate. A patio measurement does not tell you where a base plate can be fixed, and a nominal size label does not provide every installation dimension. Use the selected model's drawing when discussing foundations or placement with an installer.
The Australian POWER+ selector offers several sizes and configurations. Use it to shortlist candidates, then compare drawings for those exact options. Do not combine a dimension from one model with a post layout from another.
Draw furniture in its working position
| Activity | Show on your sketch |
|---|---|
| Dining | Table, occupied chairs, chair pullback and serving route |
| Lounging | Sofa depth, side tables and the route around the seating |
| Two activities | A clear connection between zones without crossing occupied seats |
| House-side position | Door opening, steps and the route past the structure |
| Future side accessories | The side opening and any space required for their operation |
Compare shape as well as area
For a simple planning example, a 3 × 4 metre rectangle has 12 square metres of nominal area, while a 4 × 4 metre square has 16. That arithmetic does not describe the exact clear interior of a product. The extra area is useful only if it falls where your layout needs it.
A rectangular table may work better when the longer roof direction follows the table. A square arrangement may give more balanced circulation around a lounge. Rotate the furniture and the candidate footprint on the sketch before deciding that you need a larger kit.
Run a full-size test
Use removable markers to represent the proposed posts and furniture on the patio. Open the house door, pull out the chairs and walk from the house to the garden. Try carrying a tray or moving the largest item you expect to use. This is a layout exercise, not permission to drill or install anchors.
Mark anything that does not work and identify the cause. A furniture change may solve a circulation problem without changing the pergola. A fixed door or structural obstacle may require a different configuration instead.
Confirm the site separately
Once the layout works, have the supporting surface, foundation arrangement and selected configuration assessed. The local FAQ discusses site-dependent foundation requirements; a visually level patio alone does not establish structural suitability. Any applicable local approval requirements also need their own check.
Save the final sketch with the model, size, drawing revision and intended accessory locations. That gives the supplier and installer the same starting point, while leaving exact construction dimensions to the approved product and project documents.