Assess Current Windows
1-2 hoursIdentify single-pane, failed seals (fog between panes), rot, and air leaks. Check for lead paint in pre-1978 homes.
Field context
This workflow is part of 4 niche fields
Free step-by-step window replacement for homeowners replacing windows. Plan window replacement with calculators and checklists covering assess current.
Identify single-pane, failed seals (fog between panes), rot, and air leaks. Check for lead paint in pre-1978 homes.
Compare insert (retrofit) vs full-frame replacement, vinyl vs fiberglass vs wood, and U-factor/SHGC ratings for your climate.
Measure width and height at three points — order smallest dimension minus 1/4 inch for insert fit.
Remove old window, prep opening, set new window level and plumb, shim, screw, and foam insulate gaps before trimming.
Estimate energy savings from efficient window upgrade. · Track post-installation energy bill changes.
Budget $300-$800 per window for materials and install.
Calculate total window area for energy analysis.
NFRC label ratings explained for US climates.
| Rating | Measures | Northern Climate | Southern Climate |
|---|---|---|---|
| U-factor | Heat loss | ≤ 0.27 | ≤ 0.40 |
| SHGC | Solar heat gain | 0.25-0.40 | ≤ 0.25 |
| VT | Visible light | 0.50+ | 0.40+ |
| Air leakage | Drafts | ≤ 0.3 cfm | ≤ 0.3 cfm |
Window replacement ROI is 10-20 years on energy savings alone — justify with comfort, noise reduction, and home value.
Retrofit insert windows save 40% on labor vs full-frame when existing frame has no rot or damage.
Standard expanding foam can bow vinyl window frames — always use window-and-door low-expansion foam.