What to look for from inside
Daytime condensation on the room side of the glass is often a humidity issue. Fog or mineral film between panes usually means a failed insulated-glass seal. Drafts at the lock or meeting rail, soft drywall at a sill, or a sash that will not stay open are reasons to have a contractor look — not reasons to accept the first 'whole-house special' pitch. We will not invent energy-savings percentages.
