Why This Matters
Low-e coatings on double-pane windows are optimized for winter heat retention. In summer, they still allow significant solar heat gain. Window film corrects this seasonal imbalance.
Near Temescal Regional Recreation Area in Berkeley, west-facing windows at low afternoon sun angles drive the highest interior temperature increases. This is especially problematic for multi-family residence installations, which condos and apartment buildings benefit from film to reduce hvac load and improve tenant comfort.
California's Title 24 energy code sets minimum window performance standards for new construction. Window film can bring older homes up to — and beyond — those standards at a fraction of the cost of window replacement.
The Solution
Low-e retrofit film is the most cost-effective upgrade for older single-pane windows. It adds a low-emissivity layer that dramatically improves thermal performance without full window replacement.
Perforated film solves the privacy-versus-light tradeoff for street-facing rooms. The micro-hole pattern maintains outward visibility from inside while blocking the view from outside during daylight hours.
Retrofits existing glass with a low-emissivity coating for improved thermal performance.
Climate & Solar Performance
Properties near Temescal Regional Recreation Area in West Berkeley, Berkeley experience afternoon heat gain conditions that make window film particularly effective. Low-E Retrofit Window Film is specifically engineered to address this solar exposure.
Effective against afternoon heat gain
Rated for multi-family residence protection
Professional installers available in Berkeley
10–15 year manufacturer warranty
Installation Guide
Most window film manufacturers require professional installation to honor the warranty. DIY application voids coverage on most premium products.
Install time
30–45 min
Per window
$150–$400
Cure time
30 days