Freeze-thaw and snow
NOAA's engineering weather data for Spokane records an average of about 72 freeze-thaw cycles a year and lists a 50-year ground snow load of 42 pounds per square foot. Exterior concrete has to handle repeated freezing, piles of plowed snow, meltwater and deicers. Air-entrained concrete, correct finishing, no added water at the site and careful curing give slabs the best chance. Ask your contractor what mix they'll use and whether it's air-entrained.
Frost depth and flatwork
A joint City of Spokane and Spokane County codes policy sets frost depth at 24 inches below finished grade unless a soils investigation supports a different depth. Driveways and patios aren't usually founded that deep, so a compacted, well-draining base is essential. Saturated soil under slabs freezes and heaves. Drain water away from slab edges and keep downspouts from dumping onto concrete.
Deicers and sealing
Deicing salts damage concrete, especially new and decorative concrete. Sand gives traction without chemical damage. Sealing exterior concrete helps resist freeze-thaw and deicer damage; reseal as recommended.
Cold-weather pours
Concrete must not be placed on frozen ground or allowed to freeze while curing. Contractors use heated water, accelerators and insulated blankets in cold weather. Many schedule flatwork for spring through fall.
Snow removal
Metal plow blades and snow blower augers can chip concrete edges and decorative surfaces. Use a plastic shovel on new or stamped concrete.
Driveway approaches
Replacing a driveway approach usually needs a permit from the City of Spokane or Spokane County.
Before you hire
Ask Spokane concrete contractors what mix they'll use, whether it's air-entrained, how they'll prepare the base and drainage, how they'll cure the slab, and whether they recommend sealing. Use L&I's contractor lookup to check their Washington registration, bond and insurance.
Cracks and repair
Seal cracks before winter so water can't get in and freeze. Sections that tilt toward the house should be lifted or replaced. Widespread scaling, crumbling or heaving usually means replacement. Surface damage on a sound slab can sometimes be resurfaced.
Garage aprons and steps
Garage aprons and entry steps take the worst of snow, ice and deicers that drip off vehicles and boots. Proper air entrainment, sealing and a slope that drains away from the garage help them last. Steps on shallow footings can heave; ask how the contractor will support new steps.
Timing
Most Spokane flatwork is scheduled between spring and fall. Book early in the year.
Decorative concrete
Stamped and colored concrete can work in Spokane with an air-entrained mix, a good sealer and careful winter care without salt.
Utilities
Call 811 before excavation, and point out private lines such as irrigation and landscape lighting, which 811 doesn't mark.
Drainage and ice
Slope driveways and walks so meltwater runs off rather than pooling and refreezing into ice sheets. Downspouts that empty onto walkways create ice every winter night; extend them to discharge onto soil or a drain instead.