Deck building and repair in Bozeman, Montana

How it works

1. Call or send a request

   Give us the address and describe the project, or what's wrong with the deck you have now.

2. We connect you

   We hand it to an independent deck builder who covers Bozeman and the surrounding valley.

3. They call you back

   The builder visits, measures, and quotes you directly.

Who calls us?

Homeowners across the Gallatin Valley: in Bozeman itself, in Belgrade next to the airport, in the fast-growing neighborhoods around Four Corners, and out west in Manhattan. Bozeman is the Gallatin County seat and had 53,293 residents at the 2020 census, up 43 percent from 2010. A lot of that growth is newer houses that came with a patio door and a single step, and older homes near downtown and Montana State University whose decks were built decades ago and are wearing out.

What can a deck builder do for you?

• New decks. Treated framing on footings dug below frost, with wood or composite boards on top, from a small landing to a two-level deck. See deck building.
• Composite and PVC decks. Boards that skip the stain-and-seal routine, on framing laid out for them. See composite decks.
• Repair and replacement. Swapping soft boards, fixing a sagging beam or a bad ledger, or tearing out a failing deck and starting over. See deck repair.
• Railings and stairs. Guards in wood, aluminum, cable or composite, and stair runs that stay solid through freeze and thaw. See railings and stairs.
• Covered decks and pergolas. A roof or pergola for summer shade and a dry spot in shoulder season. See covered decks.

Why are Bozeman decks built heavier than you might expect?

Snow. The City of Bozeman's published design criteria set a deck live (snow) load of 46 pounds per square foot, the same figure as the city's ground snow load. In plain terms, a deck here has to be framed to carry a good load of snow sitting on it, not just people and furniture. That affects joist size and spacing, beam size, and how many footings the deck needs. The city's average snowfall is a little over 91 inches a year, so a deck that's never shoveled can carry a lot of weight by February.

What else is hard on a deck in the Gallatin Valley?

• Deep frost. Bozeman's design criteria call for footings 36 inches deep for one-story buildings and 48 inches for two-story buildings, measured to the bottom of the footing. Your builder should confirm which depth the building department wants for your deck.
• Hard cold. Bozeman's record low is −46°F. Fasteners, finishes and boards go through big swings and many freeze-thaw cycles every year.
• Wind. The city lists a 115 mph basic design wind speed. Tall privacy screens and pergolas need to be built to resist it.
• Strong sun at altitude. Bozeman sits at about 4,820 feet. South- and west-facing wood boards dry, check and fade fast, and stain doesn't last long.
• Earthquake design. The city's criteria put homes in Seismic Design Category D0, one more reason the connection between a deck and the house matters.

When should someone look at your deck?

• Boards that bounce, feel spongy, or break apart around screws
• Joists or a beam that visibly sag after a heavy snow
• A railing post that moves when you lean on it
• Stairs that rock, or stringers that are dark and soft at the bottom
• The deck pulling away from the house, or a gap at the ledger
• Footings that have heaved, tipped, or left posts sitting crooked
• Rusted joist hangers, missing bolts, or nails backing out

Do you need a permit for a deck in Bozeman?

Usually, inside city limits. A third-party summary of City of Bozeman rules says only freestanding decks no more than 30 inches above grade are exempt, and that attached decks, decks higher than 30 inches, covered decks and decks over 300 square feet need a building permit from the city's Building Division. Belgrade runs its own building department for property inside its city limits. Outside the cities, the rules are different, so ask your builder who has jurisdiction for your parcel. The Bozeman deck guide explains each case and links to the sources.

Wood or composite?

Both get built here. Treated wood or cedar costs less at the start and is simple to patch, but high-altitude sun and dry air mean it needs cleaning and a new finish on a regular schedule. Composite and PVC cost more but don't rot and don't need stain. The framing underneath is treated lumber either way, and in a 46 psf snow-load town, that framing deserves as much attention as the boards. A builder can help you decide based on which way the deck faces and how much upkeep you'll actually do.

Is wildfire a concern for decks here?

On lots near timber or grass, yes. Gallatin County's emergency management office lists removing vegetation and debris from under decks among its wildfire risk-reduction steps, and the county offers free in-person home wildfire assessments. If you back onto the foothills, ask your builder about keeping the space under the deck clear and using noncombustible materials closest to the house.

When do Gallatin Valley decks get built?

Mostly from spring thaw into fall, when the ground can be dug and concrete poured. Builders' schedules fill quickly once the snow is gone, so if you want to use a new deck this summer, start talking in winter. Design, material choices and the permit application can all happen while the ground is still frozen.

Are you a deck company?

No. Bozeman Deck Builders is a referral service. We connect you with an independent builder who works at your address, and that builder handles the design, quote, permits, construction and warranty. Read our tips on hiring a deck builder before you sign anything.

Areas we cover

• Bozeman
• Belgrade
• Four Corners
• Manhattan

Planning ahead? Read our Bozeman deck guide.