Fort Collins, CO Questions
Fort Collins Deck Questions and Answers
Plain answers on what decks, covers and pergolas cost in Northern Colorado in 2026, which jobs need a permit in Fort Collins and the county, how deep footings go, what snow and wind a deck is built for, and how composite and wood hold up here.
What is the average cost of a deck in Colorado?
A new deck in the Denver market averages $9,640, and most land between $5,055 and $14,243, according to Angi's 2026 figures for Denver, the TV market Fort Collins belongs to. Per square foot that is about $22 to $55 installed. Pressure-treated wood sits at the low end, capped composite like Trex at the high end, and stairs, railings, height and covers push a deck up the range. Quotes vary by site.
How much would a 14x20 deck cost in Fort Collins?
A 14 by 20 foot deck is 280 square feet, so at Angi's Denver-area rate of $22 to $55 per square foot installed it comes to roughly $6,160 to $15,400. A low, freestanding pressure-treated deck with one short stair lands near the bottom; a composite deck attached to the house, with aluminum railings and a full stair to the yard, lands near the top. The City's deck permit adds $110 plus sales tax.
Do you need a permit to build a deck in Fort Collins?
Usually yes. Fort Collins requires a permit for any deck that is attached to the house, more than 30 inches above grade at any point, larger than 200 square feet, or serving the front door, and for replacing joists, posts, beams, stairs or guard railing. The permit costs $110 ($38.50 plan check plus $71.50 permit) plus sales tax. A small, low, freestanding platform can be exempt.
What is the most expensive part of building a deck?
Labor and the structure under the boards. Modernize puts labor at 50 to 60 percent of a deck's total cost, and much of that time goes into footings, posts, beams and joists that nobody sees. After that, the decking material and the railing are the biggest line items: composite boards and aluminum or cable railing cost several times more per foot than pressure-treated wood.
How deep do deck footings have to be in Fort Collins?
At least 30 inches for an attached deck and 12 for a freestanding one, per the City's deck guide (revised June 24, 2026). Width matters as much: the City's chart, at 1,500 psf soil, sizes each round pier by the deck area its post carries, from 12 inches across at 20 square feet to 16 at 40, 22 at 80 and 31 at 160.
Is composite or wood better for a deck in Northern Colorado?
Composite usually holds up better here, and wood costs less up front. Fort Collins sits at about 5,000 feet with strong sun, dry air and freeze-thaw winters, which dry out and check unsealed wood; cedar and pressure-treated decks need sealing every year or two. Capped composite skips the sealing and carries 25 to 50 year limited warranties from Trex, but its boards cost roughly twice what pressure-treated lumber does (Modernize) and it runs hot in direct sun.
When is the best time to plan a deck in Fort Collins?
Plan in winter, build in spring through fall. Interest in deck builders across the Denver market peaks in August, and in covered patios in May, so spring calendars fill first. Design, the City's plan review and HOA approval can all happen over the winter, and footings can be dug whenever the ground isn't frozen.
How much would a 20x20 deck cost?
A 20 by 20 deck is 400 square feet, so at the Denver-market rate of $22 to $55 per square foot installed (Angi, 2026) it runs about $8,800 to $22,000. Angi's national figure for replacing a 20 by 20 deck is $10,000 to $11,000. Composite, a second-story height or a roof push it toward the top of the range.
What does a pergola cost installed?
Angi's 2026 national average is $4,253 for a 100 square foot pergola, with most between $2,118 and $6,433, or $30 to $60 per square foot. Wood pergolas in the Denver area run $25.60 to $52.20 per square foot installed (handoff.ai). Louvered aluminum systems cost $55 to $125 per square foot.
Do you need a permit for a pergola in Fort Collins?
Yes if it is attached to the house, taller than 8 feet at any point, larger than 120 square feet, or closer than 3 feet to a lot line, per the City's Residential Pergola Guide (March 30, 2026). A pergola built on top of a deck, or one made of aluminum or composite, also needs engineered plans. The permit is $110 plus sales tax.
What is the ground snow load in Fort Collins?
35 pounds per square foot by default for homes, per the City's building code page, with frost depth at 30 inches. Loveland publishes 35 psf as well; Johnstown and Severance publish 30 psf. Larimer County's January 2026 table uses strength-level values: 55 psf up to 5,000 feet of elevation and 70 psf at 6,000 feet.
How tall does a deck railing have to be in Fort Collins?
Guards are required wherever the deck is 30 inches or more above grade, measured 3 feet out from the edge, with openings under 4 inches (4-3/8 inches on stairs). Larimer County's handout sets the guard at 36 inches minimum. Cable railings in Fort Collins need cables no more than 3 inches apart and posts no more than 4 feet apart.
Can I build a deck over a basement egress window well?
Yes, with clearance. The Fort Collins deck guide requires 36 inches of clear height from the top of the window well to the underside of the deck structure, so the escape window still works.
Does a deck need a light on the stairs?
Yes. Fort Collins requires a wet-listed exterior light at the top landing to light the stairs, and a new fixture has to be shielded and aimed down (dark-sky compliant) under a local amendment.
Can composite decking be shoveled?
Yes, with a plastic shovel. Trex says metal shovels can chip the surface and void the warranty, and that calcium chloride or rock salt can be used for ice if it is rinsed off when the weather allows.
Does Larimer County's wildfire code apply to my deck?
It applies across unincorporated Larimer County, which the county's 2025 Wildfire Resiliency Code (effective January 1, 2026) declares a wildland-urban interface area. For covered construction the deck walking surface must be noncombustible, Class A rated, fire-retardant-treated wood or ignition-resistant material, with composite allowed at a Class B rating minimum. Smaller additions and alterations have exceptions, so check with the county.
Is enclosing a covered patio a different permit?
Yes. Fort Collins treats enclosing a covered patio as a residential addition, not a patio cover, so it goes through the addition permit process rather than the $110 cover permit.
How long does a deck permit take in Fort Collins?
The City doesn't publish a fixed review time on its permit page. Plan check fees are due when you apply, plans are submitted as PDFs, and inspections are scheduled once the permit is issued. Ask Building Services at 970-416-2740 for the current turnaround.
Does a contractor need a license to build a deck in Fort Collins?
Yes. Fort Collins licenses contractors working in the city, and its deck guide lists the license classes allowed to build decks: A, B, C, C2, D, D2 and MM (MM can't build two-story decks). Homeowners building their own deck sign a homeowner affidavit instead.
Go deeper: deck cost, pergola cost, covered patio cost, deck permits, pergola permits, footings and snow load, railing code, wildfire code and composite vs wood. Towns covered: service area.
Still have a question?
Ask it in the quote form along with the address. The quote is free.