Snow load on the Palmer Divide: why your covered patio must be engineered

If you live up on the Palmer Divide — Larkspur, Monument, the high ground between them — your backyard gets buried under far more snow than Denver does. That's not just a shoveling problem. It means a patio cover built to Denver's numbers can sag, crack, or come down on you. Here's why, and what a cover built right for up here actually looks like.

The Palmer Divide makes its own snow

The Palmer Divide is the high ridge that runs east from the Front Range between Castle Rock and Colorado Springs, topping out around 7,000 feet. When storms hit it, the land forces the air up, and rising air drops more snow. Weather folks call it upslope.

The result up here is dramatic. Larkspur averages around 75 inches of snow a year, and some winters top 90. Denver averages closer to 55. A single storm that leaves 3 inches in Castle Rock can drop a foot in Larkspur, and spring storms in March, April, even May can pile on 12 to 24 inches at once. That late-season snow is the heavy, wet kind — the kind that breaks things.

Above 6,000 feet, the required snow load jumps

Here's the part most homeowners never hear about. Building codes don't use one snow number for the whole region. They set it by elevation, because higher ground holds more snow. The higher you live, the stronger your roof has to be — by law.

In Douglas County the design snow load starts around 30 pounds per square foot at Denver-area elevations, then climbs about 5 pounds for every 500 feet you go up. By the time you reach Larkspur, sitting near 6,700 feet, the required load is well above where it started — close to double the Denver number. That's not a suggestion. It's the minimum a roof has to be built to hold.

Why a Denver-built cover fails up here

Picture two identical patio covers. One sits in a Denver suburb. One sits in Larkspur. Same beams, same posts, same design. The Denver one is fine. The Larkspur one is under-built — because it's holding far more snow than it was ever sized for.

It usually doesn't fail the first winter. It fails the year a big wet spring storm finally lands all that weight at once. Beams that were "fine" for years suddenly bow, a post punches into soft ground, and the whole thing drops — sometimes onto a hot tub, a grill, or the patio set. We've been called to look at sagging covers that an out-of-area crew built to flatland numbers. The fix is almost always a tear-off and rebuild. It's heartbreaking, and it's avoidable.

What proper engineering looks like

A cover built right for the Palmer Divide isn't fancier-looking — it's just stronger where it counts. Three things matter most:

• Beam and rafter sizing. The horizontal members carry the snow. For the higher load up here, that means deeper, stronger beams and rafters spaced closer together. An engineer runs the actual numbers for your span and your elevation — not a rule of thumb.
• Post footings in our clay. Our soil out here is expansive clay that swells when wet and shrinks when dry, so footings have to go below the frost line — generally three feet down — and be sized so the posts don't sink or heave. A cover is only as strong as what's holding up the posts.
• Roof pitch that sheds. The more a roof is pitched, the more snow slides off instead of stacking up. A steeper, well-pitched cover sheds weight on its own. A near-flat cover holds every pound — which is exactly the wrong move up here.

It has to be engineered and permitted — that's a good thing

Any roof that carries snow in Douglas County has to be engineered to the local load and permitted, and an inspector checks it. That stamp means someone qualified did the math for your specific spot. It protects your family, and it protects you when you sell — a covered structure without a permit becomes a problem at closing.

We pull the permit, get the engineering done to your address and elevation, and build to it. No guessing, no "it'll probably hold."

Bottom line: snow on the Palmer Divide is heavier and deeper than most people realize, and the code knows it. If you're putting a cover over your patio in Larkspur or Monument, have it engineered for up here — not for Denver.