Missoula/Bell Field in NOAA's engineering data
NOAA's engineering weather data places the Missoula/Bell Field station at an elevation of 3,189 feet. For that station it gives a 1% summer design temperature of 89°F, with a mean coincident wet-bulb temperature of 62°F, and a 99% winter design temperature of 0°F. In an average year at Missoula/Bell Field, NOAA counts about 0 hours with the wet-bulb temperature above 73°F, and about 15 hours above 67°F.
That is the public weather record for the station. Everything below concerns a single room in your own house: how to describe the bathroom you want, what to ask the people who bid on it, and how to read what they hand back.
Measure before you shop
A tape measure, graph paper and an hour will save you from falling for a vanity that cannot fit. Draw the room to scale and mark:
- the center of the toilet drain, measured from the wall behind it and from the nearest side wall;
- the width and depth of the tub or shower, and which end the valve sits on;
- the window, its height off the floor and whether it falls inside the wet area;
- the door, the way it swings and anything it hits;
- every outlet, switch, light and the fan grille.
Take photos of each wall and of the floor around the toilet. With that sheet in hand, a showroom visit becomes a short list of things that fit rather than a long list of things you like.
Where the plumbing can and cannot go
Pipes set the shape of a bathroom budget. Keeping the toilet, sink and shower drains in their present spots is usually the cheapest plan, because a moved drain means opening the floor and finding a route with enough slope back to the main line. Ask each bidder to look at the space below the bathroom, whether that is a basement, a crawlspace or a finished ceiling, before pricing any move.
Supply lines raise their own questions. Ask where the shutoff valves for the new fixtures will be, whether old valves will be replaced while the wall is open, and what pipe material the plumber plans to use. If any supply line runs in an outside wall, ask whether it can be rerouted to an inside wall or insulated while the framing is exposed.
The shower floor and what sits under it
The base of a shower takes daily soaking and foot traffic. You have three broad options, and each bidder should say which one they are pricing:
- A one-piece pan of acrylic, fiberglass or composite, set in a bed and connected to the drain. Quick to install, with limited sizes.
- A tiled floor over a sloped mortar bed with a membrane, which can be built to any size or shape.
- A foam tray system with a bonded membrane and a matching drain, which gives a tiled look with factory slopes.
Whichever you choose, ask how the drain connects to the waterproofing, how a curb or threshold is sealed, and whether the floor is flood-tested before tile goes down. Ask to be there for the test, or for a photo of it with the date.
Walls in the wet area
Tile, stone and solid panels are surfaces. Behind them, a sheet or liquid membrane, or a board system with taped seams, does the waterproofing. Ask how high it runs, how the niche and any bench are wrapped, and how the valve body, the shower head arm and the window frame are sealed. A window inside the shower needs a sill that sheds water into the shower, not into the wall.
Fan, duct and control
General advice for any bathroom: an exhaust fan earns its keep only if the air it pulls leaves the house. Ask the remodeler:
- What airflow the fan is rated for, and how that was matched to the room and any separate toilet space?
- Where the duct ends: a roof cap or wall cap outdoors, not an attic or soffit?
- How long the duct is, what it is made of and how many bends it has?
- Whether a duct running through unheated space will be insulated?
- What control keeps it running after you leave: a timer, a humidity switch or both?
Quiet units get used. Ask for the sound rating on the model being quoted.
Montana's construction contractor license
Since January 1, 2026, Montana has required construction contractors to hold a license from the Montana Department of Labor & Industry. Contractors with an active Montana registration on December 31, 2025 were converted to the new license.
Questions to put to each remodeler about that rule and the work around it:
- Does the department's construction contractor license apply to this bathroom job, and if so, what is the license number?
- Which city or county permits does the work need, and who pulls them?
- What state license, if any, covers the plumbing and the electrical work, and who holds it?
- Are the plumber and electrician on your payroll or subcontractors?
Ask for proof of liability coverage and workers' compensation, and call your insurer if you have questions about your own homeowner's policy during the job.
Setting written bids side by side
Hand every remodeler your scaled drawing and the same written list. A bid you can compare names:
- demolition, haul-away and how the hallway and floors will be protected;
- each drain or supply line that moves, listed separately;
- the shower base type and the waterproofing product, by name;
- tile, panels or stone by product and size, with the area covered and the grout;
- the vanity, top, faucet, toilet, valve and trim with model numbers;
- the fan model, duct route and control;
- lighting, outlets and any heated floor;
- permits, inspections, cleanup and the written warranty.
Ask how many days the room will be out of service and, if it is your only bathroom, how the crew plans around that. Ask how damage found behind tile or under the floor will be photographed, priced and approved before work goes on. Tie each payment to a finished stage rather than a date on the calendar.