Windows in Milwaukee leak heat for the whole heating season, fastest on the lake side. Original sash in Cream City openings whistle from the first cold week and never get a mild month off. Weight pockets pull air. Brick and stone sills crack, and the joint under the stool wets the plaster. A storm that will not latch is a nightly draft while the boiler runs. Fogged glass is a dead seal, not rot.
East walls take lake wind and wet snow. North walls take the long temperature drop that makes a bedroom unusable no matter what the thermostat says. Paint will not stop water already behind the casing. If the plaster under the stool bubbles only after lake storms, call it a leak. Nightly sweat on the glass is condensation or a failed seal, not automatically a leak. A painted-shut sash in a sleeping room is its own urgency.
Openings in old brick are rarely a catalog size, and the wall is thick. Ask what happens to the stool, the apron, the brickmold, and the storm. Ignore the masonry joint and the new unit leaks in the first driving snow. Divided lites on a facade may be something you mean to keep. Cords, weights, and locks are still the right repair when the wood is sound. Say which of those you actually need.
This climate runs a draft for months, so a small gap is not a small thing. Hardware can wait. A hole you feel with your hand cannot. Interior trim and exterior wrap change the look of a duplex facade when only one unit is being done. If you share the building, say so. Name the openings that fail, not every window in the house, or the call swells past the heat loss you meant to stop.
Lead with draft, leak, fog, or a sash that will not move, and name the lake side if that is the wall. Milwaukee will pull heat through that gap until spring. Call the number on this page.