How Big Can I Build My Wooden Pergola, Lean-To, or Gazebo?
- Bjørn Content Team
- Feb 24
- 3 min read
When customers ask us this question, what they’re really asking is:
“Am I limited by the kit — or by my imagination?”
The short answer?
You can build as large as you can imagine — as long as you use the right brackets and keep your spans properly supported.
Let’s break it down by structure type.
Wooden Pergola Kits: Virtually Unlimited in Both Directions
With a wooden pergola kit from Bjorn, you can expand in both width and depth.
That’s because our bracket system includes:
Standard 4-corner bracket kits
Extender kits
5-way brackets
Additional foot brackets
These components allow you to create multiple sections in either direction.
What is a “section”?
A section is simply a horizontal span of lumber between two vertical supports.
For example:
A 12' x 12' pergola = 1 section
A 12' x 24' pergola = 2 sections (two 12' spans)
A 24' x 24' pergola = 4 sections
If you'd like to build a 12' x 24' pergola, you would:
Purchase a standard pergola kit
Add one pergola extender kit
That creates two supported 12’ spans — maintaining structural integrity while doubling your footprint.
With the right combination of hardware, pergolas can be expanded infinitely in both directions.
Lean-To Kits: Expandable in Width
Lean-to structures are typically used for:
DIY carports
Horse sheds
Garden sheds
Equipment storage
Most lean-to builds don’t require excessive depth. In fact, the majority of builds fall under 14' deep, which comfortably fits vehicles, equipment, or livestock shelter needs.
Because of this, our lean-to kits are designed to:
Expand infinitely in width
Maintain proper structural support in depth
If you need more width?Add extender brackets and create additional sections.
While most customers don’t require expansion in both directions, we’ve had increasing requests for that flexibility — and we’ve begun designing hardware to meet those needs.
Gazebo Kits: Expandable in Depth
Our DIY gazebo kits are commonly used for:
Backyard pavilions
Outdoor entertaining spaces
Garden structures
Greenhouses
Sheds
Gazebo kits allow widths up to 20 feet with a standard kit configuration.
For most backyard builds, that width is more than sufficient.
Where expansion typically occurs is in depth.
For example:
If you're building a 20' x 20' gazebo, here’s how that works:
The 20' width is supported within the design.
The depth follows our 12’ span rule (more on that below).
To achieve a full 20' depth without unsupported spans over 12’, you would select a 2-section gazebo kit from the dropdown option on the product page.
This creates:
(2) 10' spans
Proper vertical support
Long-term structural stability
You can add up to four sections (three extender kits) for even larger builds.
The One Rule That Matters Most: The 12’ Span Rule
No matter what structure you’re building, this is the guiding principle:
Keep horizontal spans of lumber 12 feet or less — unless you add vertical support underneath.
Why?
Because wood — even strong 6x6 lumber — will sag over time if unsupported across longer distances.
Yes, 6x6 posts resist warping better than 4x4 posts.But even 6x6 lumber is still wood.
Keeping spans at 12’ or under ensures:
Long-term structural integrity
Reduced sagging
Fewer wood replacements over time
A cleaner, more professional finished look
If your desired width or depth exceeds 12’, simply create multiple sections using extender kits.
Real-World Example
Building a 12’ x 24’ Pergola
Create (2) 12’ sections
Use a standard kit + pergola extender kit
Building a 20’ x 20’ Gazebo
Select a 2-section gazebo kit
Creates (2) 10’ spans in depth
Same logic applies to lean-to structures when expanding width.
So… How Big Can You Go?
You can build your pergola, lean-to, or gazebo as large as you can imagine — provided you:
Use the correct brackets
Break large spans into 12’ (or smaller) sections
Add vertical supports where needed
Our bracket systems are designed to scale with your vision.
Whether you're building:
A backyard pergola retreat
A large-scale entertaining pavilion
A multi-bay carport
A custom horse shelter
Or a statement-making gazebo
The size isn’t the limitation.
The only real limit is how you section and support it.
And with Bjorn Woodworks — that’s completely in your control.**
