How long do windows last?
Updated August 2026
Windows last 20–40 years, but the frame and the glass age on two different clocks. The frame is the long-lived part: vinyl runs 20–40 years, aluminum 20–25, and wood 30-plus if it is kept painted and dry. The insulated glass unit, the sealed double or triple pane, is the weak link, and its seal typically fails at 10–20 years, letting the panes fog even while the frame is fine. So a window can look sound and still need attention decades before the frame is done. Seal failure and frame material are what set where any window lands.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| Vinyl frame | 20–40 years | Low-maintenance and rot-proof; can warp under extreme heat |
| Wood frame | 30+ years | Longest-lived if painted and sealed; rots fast if water gets in |
| Aluminum frame | 20–25 years | Strong but conducts heat and cold, so it sweats and drafts |
| Fiberglass / composite | 30–40 years | Stable and durable; a premium newer option |
| Insulated glass seal | 10–20 years | The first thing to fail; fogging means the seal is gone |
| Neglected sills and flashing | Cut years off | Water at the sill and frame is what rots and warps windows early |
Signs yours is near the end
- Fog, haze, or condensation trapped between the panes that never wipes away
- Noticeable drafts, or a cold edge you can feel with your hand in winter
- Sashes that stick, will not stay up, or no longer latch and seal
- Visible rot, soft spots, or peeling paint on wood frames and sills
- Cracked, hardened, or missing glazing and caulk around the frame
- Rising heating and cooling bills traced to the windows and a sun-faded interior
How to add years
Frames outlast their glass when water stays out and the seals stay fresh. Re-caulking and re-glazing the frames every few years keeps rain from reaching the wood and stops drafts before they force the heat to run harder. Keep sills and weep holes clear so water drains instead of pooling, and repaint wood frames on schedule, since bare, wet wood is what rots a window early. A drafty window is often a worn weatherstrip or a failed seal, not a lost cause, and the drafty-window guide sorts a quick fix from a real replacement. Run through the sashes, seals, and hardware once a year using the windows maintenance checklist. When the glass fogs across most of the house or the frames are rotting, the replacement-timing guide covers when new units, at $500–1,000 each, finally pay off in comfort and energy savings.
What it costs to replace: plan on $500–1,000 per window installed. Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
OnOtto tracks your window seal checks age and service history, and warns you before end of life instead of after the flood.
Track your home's systems, free for 30 daysFrequently asked questions
Can you fix a foggy double-pane window without replacing it?
Sometimes, but it is a compromise. Once the seal on an insulated glass unit fails, moisture gets between the panes and fogs them, and the insulating gas is gone. Defogging services drill the pane, dry it, and reseal it for $75 to $150, which clears the haze but does not restore the lost energy efficiency. A better long-term fix is replacing just the glass unit (the sealed pane package) while keeping the existing frame, often $150 to $400. Full window replacement only makes sense if the frame itself is failing too.
Are foggy windows a sign I need all new windows?
Not necessarily. Fog between the panes means one seal has failed, and you can replace that single glass unit while keeping the frame, which is far cheaper than a whole window. Whole-house replacement makes sense when many windows fog around the same time (they were installed together and age together), or when the frames are rotting, drafty, and hard to operate on top of the fogging. If it is one or two units on an otherwise sound set of windows, fix those individually and leave the rest alone.
Do vinyl or wood windows last longer?
It depends on upkeep. Wood frames can last 30 years or well beyond, and in historic homes far longer, but only if they are kept painted and dry; let water in and they rot within a decade. Vinyl frames last 20 to 40 years with essentially no maintenance, never rot, and never need painting, though they can warp under extreme heat and cannot be refinished. For a low-effort, low-cost window, vinyl wins. For longevity, looks, and the ability to repair rather than replace, well-maintained wood has the edge.