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 Southern Exposure in San Francisco, energy-efficient double-pane glass with low-e coatings can be enhanced further with retrofit film. This is especially problematic for single-family home installations, which the most common residential application; window film reduces heat gain and protects furnishings.
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.
Micro-perforated pattern provides one-way privacy and solar control without blocking the view.
Climate & Solar Performance
Properties near Southern Exposure in South Park, San Francisco experience low-e glass performance conditions that make window film particularly effective. Perforated Window Film is specifically engineered to address this solar exposure.
Effective against low-e glass performance
Rated for single-family home protection
Professional installers available in San Francisco
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