Arvada Pergola Footings

Most people diagnose a shade structure by looking up. Is the beam sagging, is the frame out of square, did that corner always sit like that. Fair enough, but by the time you see it from the house, it has been going wrong for a couple of years. The early evidence is six feet lower, where wood or steel meets concrete.

Crouch at each post for two minutes. That's the whole inspection. A rust track down the concrete, a sliver of daylight under one edge of a base plate, a collar standing prouder than its neighbors, a ring crack in the patio. Each one is a specific problem with a specific cause, and every one is cheaper now than after the frame racks itself out of square.

Look down, not up

A pergola is a light structure with a punishing job. It has to stay square through wind off the foothills, through heavy wet spring snow sitting on the slats, and through ground that changes volume under it every year. All of that funnels into a handful of small connections at the bottom of the posts. That's why the story gets written down there first.

Around Olde Town it's mostly age and water: older patios, posts set right onto slab or into a shallow hole, and twenty years of runoff finding the same low corner. Out in Candelas, Leyden Rock, and Whisper Creek the failures come younger, because plenty of those structures got built into backfill and graded fill that hadn't finished settling. A three-year-old pergola with one low corner isn't a bad pergola. It's a footing standing in dirt that's still moving.

What you find at the bottom of the post

Almost no weight, which is the whole problem

Heavy buildings resist wind by being heavy. A pergola has nothing to offer there. Wind pushing under an open roof creates lift, and if the connection at the bottom of each post can't take tension, the structure tries to pick itself up in the gusts and works loose one storm at a time. Loose leads to racked, and racked is a frame that won't come back square no matter what you do below it.

So the footings work in two directions. Down for the load, which is easy. Up against uplift, which nobody plans for. That means real depth, steel in the pier tied to hardware cast in rather than drilled later, and a post base rated to resist tension instead of just keeping wood from sliding. Looks like overkill for something holding up shade. In February it isn't.

The two-minute check, one post at a time

• Level two faces of the post, then step back and sight down the beam line
• Look for a rust track or stain running down from the base plate
• Try to slide a business card under each edge of the plate
• Press a screwdriver into the bottom inch of wood and see if it gives
• Check whether water sheds away from the post or collects at it
• Note any crack circling or radiating from the post
• Photograph each base the same way, and repeat next spring

When to do this work in Arvada

Fall is the best window for setting or resetting footings. Ground drills clean, holes stand open, and the yard recovers before you want the patio back. Spring works and is messier, since a rig on saturated ground leaves marks you'll look at all summer.

Winter isn't off the table. The top layer freezes and the auger deals with it. Frozen bearing material is the hard line; nothing gets poured onto it. So cold-month work means drilling and placing the same day, with warm mix water and protection over the fresh concrete. If the goal is shade by June, get the holes in during fall or early spring. Concrete needs its time, and your pergola builder needs posts standing before he can frame.