When someone mentions building an arbor, pergola or patio cover we all get a picture of an outdoor structure in our head. The problem is those pictures can look very different, which makes communicating what you want to a builder or contractor more challenging.
Although we can’t be responsible for how those terms are used by all trades, we can share the main differences between an arbor, pergola, and patio cover from a professional’s perspective. Here are three questions to ask to determine if a structure is an arbor, pergola, or patio cover.
1. Freestanding or Attached?
This question is the first and best way to start distinguishing between these outdoor structures. If your project is freestanding, then it is either a pergola or patio cover. A patio cover can also be attached like an arbor (we’ll go into that difference in question two). Arbors will have posts or columns on one side and be connected to a home/building on the other side. This can be a point of confusion because many blogs, images, and descriptions refer to arbors as being freestanding arches or gateways to a garden or backyard. However, when you say the word “arbor” to a professional builder or contractor they are assuming you want your structure attached to your house or another structure.
2. Roof or Rafters?
Pergolas and arbors use posts connected by joists and rafters for shade and stability, but those rafters don't keep rain or the elements out. Even if fabric or other materials are in between the rafters, if rain can get in from the top then it is considered a pergola (if freestanding) or arbor (if attached). Patio covers consist of framing over-layed with shingles or a roofing material to keep the elements out.
3. How Big is the Structure?
This is sort of a trick question: there are no size guidelines differentiating arbors/lattices, pergolas, and patio covers. All three structures can be small or expansive based on what you want. Some may argue that smaller freestanding structures are considered arbors, but unless the structure is attached to a home or building it is still considered a pergola.
Here’s a simple definition of each structure
based on the questions above:
An outdoor structure of any size that uses joists and rafters for shade with at least one side attached to a home or another building.
A freestanding outdoor structure of any size that uses joists and rafters for shade.
A freestanding or attached outdoor structure of any size open on the sides with framing and a roof that protects from rain and the elements.