Concrete footings in Juneau AK - a base set deep enough that frost can't get under it

Across the US, an installed residential strip footing usually costs about $5 to $19 per linear foot, counting concrete, labor, digging and forms. That's a national figure, not our price. Depth, steel, access and cold-weather protection move it here, so I look the job over in person and give you a written estimate.

If the deck is attached to the house, yes, because the city requires a building permit for attached decks, porches, terraces and patios, filed online with the Permit Center. The city lets a small freestanding deck go without one when it's under 200 square feet, less than 30 inches off the ground, and has no roof or railing. The application includes a foundation plan, and the city offers a standard one. We're fully licensed and insured, and when a permit's needed we file it and book the inspections through our Civic Access account, while for footings under anything else we ask the Permit Center before we start. On a downtown lot, check the city's avalanche maps too, since building there falls under its avalanche-area rules.

Deep enough that frost can't get under them, and the exact depth for your spot comes from the city's building staff. One footing maker gives the same instruction and points installers to local officials for the number. I confirm the depth with the city before we dig a single hole, because a footing that frost can reach gets lifted in winter and dropped in spring.

Yes, with planning, and cold here doesn't only mean winter. A Michigan concrete guide treats air at or expected to drop below 40°F as cold weather, because fresh concrete can freeze before it gains strength, and early-fall and late-spring nights get there. That guide says to pour only on thawed ground and keep new concrete at 50°F or above for at least 3 days under insulated blankets, straw or a heated enclosure. Ask any crew which of those they plan to use, and I'll tell you ours at the estimate.

Frozen ground, mostly, swelling under a footing that sits too shallow and dropping it again in the thaw. Alaska extension guidance says concrete foundations should be properly reinforced to limit that cracking and to keep radon out, and reinforced against earthquakes in line with local or state codes. It also says to close the building in and heat it through winter so the heaving and settling don't get excessive. That's why the steel gets its own lines on our estimate.

A straight tube suits a standard pier, while a bell-bottom form spreads the load over a wider base. One supplier says that wider base reduces settling in softer soil and can cut the number of piers a job needs. I'll tell you which one fits once I've seen your ground and what it has to hold.