Window installation takes 1–2 hours for one window, 1–2 days for 10–15 windows, and 4–6 days for a full house with 20–30 windows.
Most homeowners ask this question after they’ve already decided to get new windows. They want to know how long workers will be in their home and how much time to clear from their schedule.
The answer comes down to five things: window type, window size, floor level, frame condition, and weather. Once you know how each one affects the job, you can set a realistic timeline before you call a contractor.
TL|DR
- Window installation takes 1–2 hours per window, 2–3 days for 10–15 windows, and 4–6 days for a full house with 20–30 windows.
- Bay windows and bow windows take 3–4 hours each roughly 3x longer than a standard double-hung window.
- Upper-floor windows take 20–30% longer to install because crews need ladders or scaffolding to work safely.
- Hidden frame rot or water damage adds 1–3 hours per window and is the most common cause of window installation delays.
- Cold temperatures below freezing slow caulk curing and shorten working hours, which extends winter window installation timelines in Western Idaho.
How Long Does It Actually Take to Install a Single Window?
One standard window takes 1–2 hours to install from start to finish. That includes pulling out the old window, checking the window frame for rot or damage, fitting the new unit, sealing it, and cleaning up.
If your window is a basic double-hung window on the ground floor with no damage around the rough opening, you’re looking at closer to one hour. If there’s frame damage or a tricky fit, add another 30–60 minutes.
How Long Does It Take to Replace Multiple Windows?
A professional crew can install 5–7 standard windows per day, or 3–4 complex windows per day. If you have 15 windows, you’re looking at 2–3 days with a solid crew. A mix of standard and complex windows say, bay windows on the front and double-hung windows everywhere else stretches the timeline.
| Number of Windows | Window Type | Estimated Time |
| 1 | Standard double-hung | 1–2 hours |
| 5–7 | Standard | 1 day |
| 3–4 | Complex (bay, bow) | 1 day |
| 10–15 | Mixed | 2–3 days |
| 20–30 | Mixed | 4–6 days |
Factors to Consider When Replacing Windows
Window type, window size, upper-floor access, hidden frame damage, and bad weather are the five things that add the most time to a window installation job.
Window Type
Bay and bow windows take 3–4 hours each about 3x longer than a standard double-hung window. Bay windows and bow windows have multiple connected window panes and more complex window framing.
They weigh more and need more than one person to position correctly. If your home has a large bay window at the front, block out half a day for that unit alone. Casement windows, awning windows, and picture windows usually take 1.5–2.5 hours depending on size.
| Window Type | Average Install Time | Why It Takes That Long |
| Double-hung window | 1 hour | Simple frame, single unit, easy access |
| Casement window | 1.5–2 hours | Hinged frame needs careful alignment |
| Awning window | 1.5–2 hours | Top-hinged operation requires precise leveling |
| Sliding window | 1.5–2 hours | Track alignment adds time |
| Picture window | 2–3 hours | Large glass, heavy unit, two-person lift |
| Bay window | 3–4 hours | Multiple units, angled framing, structural support |
| Bow window | 3–4 hours | Curved frame, 4–6 connected units |
| Sliding glass door | 2–3 hours | Wide opening, heavy frame, track installation |
Window Size
Large picture windows and sliding glass doors take 2–3 times longer to install than a standard bedroom window.
A big picture window can measure 60 inches wide or more. Getting that into an opening accurately, without cracking the insulated glass unit (IGU) or damaging the window frame, takes time and needs two people. Larger glass also means more work at every stage:
- More weatherstripping to cut and fit around the frame
- More flashing tape to apply across the exterior edges
- More exterior caulk to run without gaps
- More low-expansion foam to fill the rough opening without bowing the frame
- More time to check level and plumb before securing
What Floor the Window Is On
Upper-floor windows take 20–30% longer because workers need ladders or scaffolding to reach them safely.
Setting up a ladder safely, climbing with tools, and positioning a window from height all add time. If your second-floor windows face a narrow side yard, expect the upper end of that range.
| Floor Level | Access Method | Added Time |
| Ground floor | Direct access | No added time |
| Second floor | Extension ladder | +20–30% per window |
| Third floor | Scaffolding | +30–50% per window |
| Basement egress | Ground excavation | +45–60 minutes per window |
Frame Damage Found During Removal
Hidden frame rot or water damage adds 1–3 hours per window and is the most common cause of installation delays. You don’t always see it until the old window comes out. The installer needs to repair:
- Rotted sill plates at the base of the window opening
- Damaged jack studs on either side of the rough opening
- Compromised head jamb wood above the window
- Water-damaged sheathing behind the exterior casing
- Soft or crumbling window sill wood along the bottom edge
Watch for these signs before your installation day:
- Soft or spongy wood around the existing window frame when you press on it
- Paint peeling on the interior wall directly below a window
- Visible water stains on the window sill or interior casing
- Gaps between the window frame and the surrounding wall
- A window that’s hard to open or close due to a warped frame
- Condensation or fogging between the glass panes
Weather Conditions
Rain, snow, or extreme heat can delay window installation by 25–50%. Silicone caulk and foam backer rod both have temperature ranges for proper adhesion. Most crews pause work in rain rather than install over a wet rough opening.
| Weather Condition | Impact on Installation | Delay Range |
| Rain | Open rough openings can’t get wet | Job paused entirely |
| Snow | Slippery conditions, cold sealant | 25–50% slower |
| Below 40°F | Caulk and flashing tape won’t adhere properly | Job rescheduled |
| Above 95°F | Silicone cures too fast, crew fatigue | 10–20% slower |
| High winds | Hazard on ladders, scaffold instability | Upper-floor work paused |
Schedule Your Window Installation
The Window Source of Western Idaho installs windows across Boise, Meridian, Nampa, Caldwell, and the full Treasure Valley. Every job comes with a 10-year labor warranty and a lifetime product warranty. Call us today to schedule your free estimate.
FAQs
How long does window installation take for 10 windows?
Ten standard double-hung windows take about 1.5–2 days for a professional crew. Add another half day if the job includes bay windows, upper-floor access, or frame repairs.
Can all my windows be installed in one day?
Yes, if you have 5–7 standard windows with no frame damage and ground-floor access. Bay windows, bow windows, or upper-floor windows needing scaffolding push that past one day.
What slows down window installation the most?
Hidden frame rot or water damage behind the old window adds 1–3 hours per window and can’t be skipped without causing air leaks and water infiltration long-term.
Does cold weather affect window installation in Boise?
Yes. Most exterior caulks and flashing tapes stop adhering correctly below 40°F. The Window Source of Western Idaho plans winter installs around daily temperature forecasts to make sure every air seal holds.
Do I need to be home during window installation?
Be available at the start and end of the job. Stay reachable so the crew can get fast decisions if they find frame damage or a rough opening that needs repair.