California Window Insulation 2026 — Energy-Saving Without Replacement
Replacing windows costs $10K-$30K. Window insulation kits add R-value for under $50. Real options.
If your windows are single-pane or older double-pane, full replacement is $10,000-$30,000. Window insulation kits add real R-value for under $50 per window.
Quick Comparison
| Pick | Best For | Approx Price |
|---|---|---|
| Window Film Kit | Frost King Window Insulation Kit | $15-$25 |
| Weather Strip | M-D Building Products Foam Weatherstrip | $8-$15 |
Our Picks
Heat-Shrink Window Film
{inline(P['frost_king'], 'Frost King kit')} adds R-1 to R-2 to single-pane windows. 30-min install per window. Removes seasonally.
Weatherstripping
Self-adhesive foam around window frames. Stops drafts. Same effect as $1,000+ window replacements for $10/window.
Permanent Solutions
Cellular shades + insulation kit + weatherstripping = full window replacement effect at 5% the cost.
Need help with installation? Book a service appointment or get a free quote. Same-day available across California.
Frequently Asked Questions
Window film really work?
Yes — measurable temperature difference. Removes seasonally.
Replace single-pane windows?
If you can afford $10K-$30K, yes. Otherwise insulation kits + cellular shades.
How long does film last?
Heat-shrink: one season. Reusable insulating panels last years.
Winter guides from our crews
What to buy for holiday lights, heat, hot water and rain season, written by the California installers who put it in.
- Weatherstripping and Door Sweeps
- Smart Thermostats That Fit
- Permanent vs Plug-In Lights
- Lights Tripping the GFCI?
- Tankless vs Tank in Winter
- Safe Space Heaters
- Garage Heater Guide
- Gutter Guards Before Rain Season
- Rain-Season Drainage
- Heated Bathroom Upgrades
Get it installed
