Windows
Replacing windows
What building codes ask of windows, what changes in an older or historic house, and how to judge condensation and warranties before you replace.
10 answers
- Condensation on the Inside of Windows: Causes and Fixes Water or frost on the room side of the glass means humid indoor air is meeting a cold surface. How to tell a humidity problem from a window problem.
- Egress Window Requirements for Bedrooms and Basements The 2024 model-code minimums for an escape window (5.7 sq ft of opening, 24 in high, 20 in wide, sill no higher than 44 in) and when a replacement is exempt.
- Lead Paint on Old Windows: How to Know If It's a Hazard Why painted windows in pre-1978 homes are a common source of lead dust, what EPA's newer dust rule changed, and how inspections differ from risk assessments.
- Replacing Windows in a Historic Home or Historic District National Register listing alone does not restrict a private owner; local historic district rules can. How window review works and who gets tax credits.
- Replacing Windows in a Manufactured or Mobile Home Manufactured homes follow HUD's federal code, not the IRC. What it requires of escape windows, wind-zone ratings, safety glass and labels before you replace.
- Storm Windows vs. Replacement Windows: How to Decide What low-e storm windows do over old single-pane windows, what federal research found on savings, and the conditions that point to full replacement instead.
- When Building Codes Require Tempered Glass in Windows The code's hazardous locations for glass near doors, tubs, stairs and large low panes, how to spot the safety-glass mark, and what replacement glass must meet.
- Wildfire-Resistant Windows: What the Codes Require How windows fail in a wildfire, the glazing rules in the International WUI Code and California's 2025 WUI code, and what to ask before replacing windows.
- Window Fall Prevention: Sill Heights, Stops and Guards Why screens do not stop falls, the code's 24-inch and 72-inch thresholds, and when replacement windows must come with an opening control device.
- Window Warranties Explained: Full, Limited and Lifetime What federal law requires a window warranty to disclose, what 'lifetime' can mean, and why glass, frame, finish and labor are often covered separately.
ENERGY STAR sets its window criteria by climate zone, and it bases them on ratings certified by the National Fenestration Rating Council (ENERGY STAR). A window that qualifies in Minnesota is not judged by the same numbers as one in Florida, so the rating to look for depends on where the house is.