The single most common reason a pergola gets sent back is not quality. It is that it did not fit. On a quarter acre you can afford to guess. On a city lot you cannot.
Measure the footprint, not the roof
Listings quote the roof size, because that is the bigger, better sounding number. A 12x14 pergola has a roof that measures roughly 12 feet by 14 feet, but the posts sit inside that, and the roof overhangs them.
What you need is the flat usable area of your yard. Measure it at ground level, corner to corner, and write both numbers down.
Subtract your clearance
Now take away the space you need to actually live around the structure:
- Two feet on any side you walk past. Less than that and you are squeezing between a post and a fence every time.
- Three feet on the side with the dining chairs. A chair needs room to push back from the table.
- Nothing extra on a side that sits against a wall, if you are using a wall mounted or lean-to design.
Whatever is left is your real maximum. Compare that to the footprint on the product page, not the roof size.
Look up
People measure the ground and forget the sky. Before you order, check for overhanging branches, the gutter line, the height of your ground floor windows, and any service cable crossing the yard. Standard pergola height is around seven to eight feet at the eaves. If a branch sits at six, you have a problem that a tape measure on the lawn will never reveal.
Check what you are standing on
Concrete, pavers and compacted gravel are all fine. Lawn is workable if it is level. The failure case is a yard that falls away across the footprint, which is more common than people think because you do not notice a gentle slope until you put a straight edge on it.
Lay a long board across the space and put a level on it. If one end is more than a couple of inches off, level the ground or build a base before the pallet arrives, not after.
A worked example
Say your yard is 16 feet wide and 20 feet deep. One long side is the house wall, the other is a fence you walk along, and you want a dining setup underneath.
Take two feet off the fence side for walking. Take three feet off the far end for chairs. You are down to a usable 14 by 17. A 12x14 freestanding pergola fits comfortably. A 14x16 technically fits and will feel like furniture in a hallway.
When it is close, size down. A pergola that leaves room around it looks deliberate. One that fills the yard wall to wall looks like a mistake.
Before you order
Two numbers written on paper: your usable footprint after clearance, and the product footprint from the listing. If the first is bigger than the second, order it. If it is close, send us both numbers and we will tell you honestly whether it works.
See also: measuring and permits.