By the end of a South Shore winter, most windows are hazy on both sides. Outside, salt spray from the roads dries into a film. Inside, condensation runs down the glass and leaves mineral marks along the bottom edge.
Spring is the best moment for a full wash: glass inside and out, frames wiped, and sliding tracks vacuumed. Salt and grit in the tracks are what make patio doors stiff, and they wear out seals if they're left all year.
Between washes, a little prevention goes a long way. Run the bathroom and kitchen fans, crack a window after showers and cooking, and wipe condensation off the sills in the morning during the coldest months.
A second wash in the fall, before the light gets short, keeps the house bright through the darker season. Window cleaning pairs naturally with a grand ménage, so many households book both together.