Plan plumbing for winter
NOAA's engineering weather data for Boise records about 78 freeze-thaw cycles a year. When remodeling a bathroom, keep water lines out of exterior walls where possible. If a fixture must go on an outside wall, insulate and air seal the wall carefully, and keep pipes on the warm side of the insulation. A frozen pipe inside a finished tile wall is an expensive repair.
Heated floors
Tile floors are cold in a Boise winter. Electric radiant floor heating under tile is a popular upgrade; it needs a dedicated GFCI-protected circuit and a thermostat. Ask the contractor and electrician about installation and operating costs.
Ventilation in a semi-arid climate
The National Weather Service describes Boise as semi-arid, and indoor air can be dry in winter. But showers still produce a lot of moisture, which condenses on cold windows, exterior walls and attic sheathing. A properly sized exhaust fan, ducted outdoors with insulated ductwork through cold spaces, prevents frost and mold in the attic. A timer or humidity sensor helps the fan run long enough.
Basement bathrooms
Many Boise homes have basements, and adding a bathroom there is a popular project. Basement bathrooms may need a sewage ejector pump if the fixtures are below the level of the main sewer line, and the slab will usually need to be cut for drains. Basements also need careful moisture control: check for water entry before finishing, insulate exterior walls properly, and provide good ventilation.
Dry air and materials
Dry winter air can shrink grout and caulk and move wood vanities. Use quality grout and sealants, and choose vanity materials that handle seasonal changes.
Permits
Bathroom remodels involving plumbing, electrical or structural work in Boise need permits from the City of Boise or Ada County. Basement bathrooms often involve several inspections.
Before you hire
Ask Boise bathroom remodelers for an itemized proposal, how they'll keep plumbing out of cold walls, which waterproofing system they use, how they'll vent the fan, and what their workmanship warranty covers. Look up the contractor's Idaho registration with DOPL.
Water heaters and bigger showers
Boise's cold incoming water in winter makes water heaters work harder, and a remodel that adds a larger shower, a rain head or a soaking tub can outrun an existing tank. Ask your plumber to check whether your water heater can keep up, and whether a larger tank, a tankless unit or a heat pump water heater makes sense for your house.
Accessibility and aging in place
Many Boise homeowners remodel with the long term in mind: a low-curb or curbless shower, grab bars anchored into blocking, a handheld shower on a slide bar, a bench, comfort-height toilets and slip-resistant tile. Planning these during the remodel costs far less than adding them later.
Schedule
If it's your only bathroom, plan where you'll shower during the work, and ask for a written schedule that shows inspections and material lead times.