I'm buying a house - what should I check about the windows before closing?

Buying a house is exciting, and windows are one of the most important things to evaluate before you close — they're expensive to replace and have a huge impact on comfort and energy bills. Here's what to look for during your walkthrough.

Start with the glass itself. Look for any fogging, condensation, or a hazy film between the panes. This is called seal failure (or "blown seals"), and it means the insulating gas has escaped and the window is no longer performing efficiently. It won't get better on its own — the sealed unit needs to be replaced. On a sunny day, look at the glass from an angle to spot this more easily.

Check the frames and operation. Every window should open, close, and lock smoothly. Stiff or painted-shut windows are a red flag — they may indicate deferred maintenance or, worse, that someone painted over them to hide rot or damage. On wood or wood-clad frames, press gently on the corners and sill with your finger. Soft or spongy wood means rot, which can spread and affect the surrounding wall structure.

Look at the seals around the frame. Check the caulking and weatherstripping where the window meets the wall, both inside and outside. Cracked, missing, or peeling caulk lets in air and moisture. In Ottawa's climate, even small gaps cause significant heat loss and can lead to ice damming and interior moisture problems over winter.

Consider the age and energy performance. Most windows have a manufacturing date stamped on the frame or between the glass panes. Windows older than 20-25 years are likely single or early double-pane, and won't meet modern ENERGY STAR standards for Ottawa's Climate Zone 6. Ask the seller for any records on past replacements. If the house still has original 1990s or earlier windows, budget for replacement — it's a strong negotiating point.

In Ottawa specifically, the combination of -30°C winters and hot humid summers is brutal on windows. Watch for frost or ice on the interior glass in winter photos (sometimes visible in listing photos), which signals poor insulation value. Also check basement windows carefully — they're often the oldest and most neglected, and frequently have moisture or rot issues.

On the practical side, count the windows and note any specialty shapes — bay windows, skylights, or oversized picture windows. These cost significantly more to replace than standard sizes. A full house replacement in Ottawa typically runs $8,000–$15,000 for 10–15 standard windows, so knowing what you're working with helps you negotiate or plan your budget.

If you spot concerns during your walkthrough, it's worth having a home inspector specifically note window conditions in their report. That gives you documentation to negotiate a price reduction or ask the seller to address issues before closing.

If you'd like a professional window assessment after you take possession, Ottawa Window Pros offers free consultations — we can walk through the house, identify what needs replacing, and prioritize based on your budget.