Building a Pergola

It depends who you talk to: I’ve heard them referred to as pergolas, arbors, colonnades, a trellis, and (no joke) “one of those garden thingies.”  

Whatever they’re called, I enjoy building them. I like the balance of macro work (digging holes, cutting timbers) and micro work (awesome layout tricks, scroll cuts). There’s just enough of each to tickle my carpenter’s ganglia without sending me to Bedlam.  

What’s more, after having built several of them I can tell you the ROI (return on investment) is awesome. A nice pergola creates a look and a space that enhances a backyard experience—even when you’re not eating dinner or playing with the kids beneath it. You can see them out the window, when walking in from the driveway, or as you mow the lawn. And while the pergola explained here is built as a stand-alone, weaving one into an existing patio or sitting area is also ideal. (See Sidebar, “Making the Connections”.) Then of course, there’s the outdoor living aspect: There is nothing like kicking back on a lazy summer evening under a pergola, dining al fresco, and spending time with family and friends. And, if you can safely weave in an outdoor fireplace situation—man, there’s a lot to love. 

If you’re a builder or remodeler, building pergolas is typically pretty profitable. A pergola is practically the definition of a luxury item, and budgets usually enable me to use nice materials and take the time required to build them well. It’s a nice departure from razor-thin margins and brain-surgery retrofits.  

A key element to building this kind of project as a freestanding unit is full-size templating. The template is what I call a “sandbox.” It’s great. I use it to mark layout, confirm proper sizing and location of the structure, and to anchor the posts. When it comes time to trim the structure I can leave the sandbox or remove it. And, there’s no string to fuss with.  

Defining Design

Proportion is key to designing a pergola that fits the space, especially in tight quarters.  

There are four design rules I like to follow, otherwise pergolas can be more of an inductive (seat-of-the-pants) rather than deductive (following a prescribed plan) process. You don’t have to be Da Vinci, but it takes a decent eye to “Goldilocks” the proportions: Too skinny and tall looks like a tower; too short and wide looks like a table. The girder should be 80 inches minimum from the ground, the same as an interior doorway. If there’s a ceiling fan, I want 88 inches under those blades, if not more. Finally, for cantilevering past the posts, my feeling is that anything less than 12 inches looks less than graceful. The pergola shown here has 18-inch overhangs. 

If you have to nestle the unit in a small space like a backyard nook, site lines from the house, interior windows and other egress points should be investigated and considered.  

In a larger space, working in basic units (8 feet, 10 feet etc.) is a little easier because there are fewer reference points to show that something is out of balance or otherwise encroaching on another visual element of the landscape. And, I build in design elements so that I can make on-the-fly tweaks to the basic design as the unit comes together. More on that later …