Why This Matters
Single-pane windows — still common in California homes built before 1980 — have almost no thermal resistance. Low-e retrofit film can cut their solar heat gain by 40–60% at a fraction of the cost of replacement.
Near Ra Solar in San Francisco, south- and west-facing windows receive the most direct solar load and benefit most from 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
The installation process is non-invasive: clean the glass, apply the film with a slip solution, squeegee out air pockets, and trim to fit. No construction, no permits, no disruption.
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 Ra Solar in Mission District, San Francisco experience south & west exposure conditions that make window film particularly effective. Perforated Window Film is specifically engineered to address this solar exposure.
Effective against south & west exposure
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