Windows in Montana fail differently in a wet western valley than on a dry, windy plain. Condensation, rotten sills, and ice on the inside glass are the mountain and valley report. Whistles, grit in the tracks, and a sash racked out of square are the plains report. Both can be true in a town that sits on the edge of a chinook. Count the elevation that is failing before you let the whole house become one order.
Log, timber, and thick older walls change the install. A full-frame replacement opens a hole that may not be square and may not be standard. Insert work leaves a frame that is a mistake if the sill is soft. Feel the wood. Storm panels and weatherstrip are honest repairs when the glass is intact and the sill is dry. A meeting rail that misses on a windy night is not a tube of sealant, especially on the Hi-Line where the gust does not let up.
Ask how the sill sheds water and what fills a deep gap. A new unit on a punky sill repeats the stain. South glass in a high valley takes a strong sun and a hard night, and that swing shows up as seals that fog and trim that checks. Ask for whole-unit figures as a spec, not as a promise that the house will use less of anything. You want fewer abandoned rooms and less water on the stool. That is the result you can see.
Cabins that sit closed up reveal the worst sills when they are opened in the spring. Full-time houses show the failure all winter as ice and a furnace that cannot catch the windward room. Say which life the building has. If a claim is open, photograph the bad elevation before the trim is painted. The lee side is a comparison, not the place to start spending the scope.
Say how many openings, which rooms, and whether the sills are soft. Name the town. Have the deductible only if the policy is already part of this. The next swing will put the water back on the glass. Call the number on this page.