Keep a North Shore cabin sound by choosing one winter plan: heat held no lower than 55°F with someone checking inside, or a full drain-down, then walking the lake-facing side every spring for wind and freeze-thaw damage. Before adding a deck, shed or entry, check the permit office: Lake County, the Town of Duluth and Two Harbors differ.
Closing up: keep the heat on, or drain it down
A cabin that sits empty through a Northland winter needs one of two plans, and a half-and-half plan is how pipes split. The first keeps the heat on. Iowa State University Extension says to leave the heat set no lower than 55°F when you're away in cold weather, and to open cabinet doors so warm air reaches pipes on outside walls (Iowa State Extension).
A power outage or an empty propane tank undoes that plan, so pair it with a temperature alert or a neighbor who goes inside. Either way, shut off and drain the lines to outdoor faucets. University of Minnesota Extension advises draining and shutting off pipes you don't use in winter, especially the ones that lead outside (UMN Extension).
The second plan is a full drain-down, for a place closed until spring. Shut the main valve or the well pump, turn off the power or gas to the water heater before draining it, open every faucet, and flush the toilets. Traps and toilet bowls always hold some water, so owners who drain down pour nontoxic RV antifreeze (propylene glycol, never automotive antifreeze) into each one. Wells, pressure tanks and tankless heaters have their own drain steps in the maker's manual; if yours aren't clear, have a plumber or well contractor walk you through the first one.
| Item | Closing in fall | Opening in spring |
|---|---|---|
| Water system | Pick one plan: heat held at 55°F or higher, or a full drain-down. Drain outdoor faucets either way | Close the drains, refill slowly, and watch every fitting and the water heater before turning its power back on |
| Doors and locks | Latches catch, weatherstripping is whole, and anyone who needs in has a code or key | Doors that drag or won't latch after the frost moved the steps; daylight under the sweep |
| Gutters and roof edge | Clear gutters after the leaves fall | Ceiling stains under the eaves; roof damage goes to a licensed roofer |
| Deck, steps and railings | Push on every post and rail before snow | Heaved posts, loose treads and soft boards, lake side first |
| Caulk and paint | Seal open joints on the lake-facing wall on a dry day | Peeling sills and trim joints that opened over winter |
| Mice and pests | Take out food; close gaps where pipes and wires enter | Droppings, chewed insulation and nesting in drawers |
| Smoke and CO alarms | Test them; note the dates | Test again and replace dead batteries |
What lake wind and freeze-thaw do to a shore cabin
A cabin on the shore takes its weather from the lake side first. Wind drives rain sideways into trim joints, window sills and the gap under door thresholds, and lake fog keeps that siding damp longer than the sheltered walls. Freeze-thaw then pries those wet joints wider each winter. That's why the lake-facing wall of a cabin in Knife River or Larsmont can need caulk and paint years before the back wall does, and why deck boards and railings on that side soften first.
Weekend heating has its own risk. University of Minnesota Extension explains that ice dams form when the upper roof is above freezing while the eaves stay below it, so melt runs down and refreezes at the edge, and the lasting fixes are an airtight ceiling and more insulation (UMN Extension). A cabin warmed up hard for a ski weekend and then left can set up exactly that.
Extension also warns that working on a roof in winter risks injury and roof damage, so a leaking roof goes to a licensed roofer. What we handle is the rest of the list: repairs to trim, siding patches, doors that bind, rotted sills, and loose deck boards and railings. Our planning range for deck board and railing repair is $800–$3,500, depending on how much framing is still sound.
Keeping an eye on it while you're away
The cheapest protection is a named person with a key who goes inside after big storms and power outages, not someone who drives past. A sensor that texts you when the temperature drops, and a water sensor by the water heater, add a second layer; check that they still report during an outage.
Access matters for repairs too. A keypad deadbolt or a lockbox lets a repair crew in on a weekday without you making the drive; our planning range for a lock or deadbolt replacement is $95–$220 per door. Text photos of each item before a visit, and group the whole list into one trip; the shore's building season is short. Also ask your insurer what it expects of a seasonal home in winter, such as heat held at a set temperature or the water shut off.
Permits for cabin projects on the shore
Along the North Shore, the office that issues permits can change within a few miles, so settle it before a project is drawn:
| Place | Office | What needs a permit |
|---|---|---|
| Knife River and Larsmont (Lake County, outside city limits) | Lake County Planning and Zoning | Land use permit for any permanent structure over 3 ft tall, such as a deck, shed or greenhouse, and for changing a building's outer dimensions. Fences 6 ft and under need none |
| French River (Town of Duluth) | Town of Duluth | Structure Land Use Permit for any building project, including one with a basement |
| Two Harbors (city) | City of Two Harbors | Building permit for a deck attached to a building or more than 30 in above grade, with 60 in frost footings and two inspections |
Outside city limits, Lake County requires a land use permit for any structure over 3 feet tall that's meant to stay, and it names decks, sheds, outhouses, greenhouses and steel containers, plus changes to a building's outer dimensions such as an enclosed entry or dormers (Lake County Planning and Zoning). Fences 6 feet and under need no permit and can sit on the property line with the better side facing out.
Two more county rules catch cabin owners: clearing vegetation within 50 feet of a waterway or 20 feet of a bluff is strictly regulated (think of the view cut that comes with a new deck), and when you apply for a permit the county checks the septic inspection, which comes due sooner for vacation rental homes and bedroom additions.
In French River, the Town of Duluth requires a Structure Land Use Permit for any building project, including one with a basement (Town of Duluth). Inside Two Harbors, the city requires a building permit for any deck attached to a building or raised more than 30 inches.
Its handout calls for frost footings at least 60 inches deep, a ledger lag-bolted or through-bolted to the rim joist or solid blocking with approved flashing, 36-inch guardrails that stop a 4-inch sphere, and inspections of the footings before concrete and of the framing (City of Two Harbors). For a cabin job, we check what your address needs, and who the office requires to pull the permit, before we quote.
What temperature should a cabin be kept at over the winter?
No lower than 55°F if you leave the heat on, which is the setting Iowa State University Extension recommends for a home left empty in cold weather. Hold it day and night, open sink cabinets on outside walls, and drain outdoor faucets. That plan depends on the heat never quitting, so add a temperature alert or a regular check.
If nobody can check on the place, a full drain-down is the safer plan.
Do I need a permit to build a deck at a Knife River cabin?
Usually. Knife River is outside Two Harbors city limits, so Lake County's rules apply, and the county requires a land use permit for any permanent structure over 3 feet tall, naming decks first. A very low platform may not reach that height, so ask Lake County Planning and Zoning before assuming it's exempt.
Setbacks from the shore, bluffs and property lines depend on your zone district, and vegetation clearing near the water is strictly regulated.
Should I drain the plumbing at a cabin I close for the winter?
Yes, if nobody will keep the heat on and check it. Shut the main or the well pump, turn off the water heater's power or gas before draining it, open every faucet, flush the toilets, and put nontoxic RV antifreeze in the traps and bowls. Drain outdoor faucets even if the heat stays on.
Follow the maker's steps for a pressure tank or tankless heater, or have a plumber show you the first time.
What should I check first when I open a cabin in spring?
Check the water first: close the drains, refill slowly, and watch every fitting, the water heater and the ceilings below plumbing for drips before you settle in. Then walk the lake-facing side for opened caulk joints, peeling sills, loose railings and heaved deck posts, and test every door, since frost moves steps and footings.
Look for stains under the eaves and for mice. Photograph what you find before you fix anything.
Opening up and finding a list? Call or text (715) 919-7956 with photos, or send your list, and tell us where the cabin is so we can confirm the permit office. You'll get a flat written quote before work starts.
Next steps. Our home repairs and odd jobs page covers the work itself. Based in Duluth, serving Superior.
Keep reading: Plaster or Drywall? Wall Repair in Older Twin Ports Homes and How to Hang Shelves and TVs on Plaster Walls in Duluth.