Why This Matters
Heat gain through glass is cumulative. A room that gains 5°F per hour through unfilmed windows will be 15–20°F above set point by mid-afternoon — forcing the HVAC system to work significantly harder.
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 historic or older home installations, which older single-pane windows benefit most from low-e retrofit film to improve thermal efficiency.
The marine layer that covers coastal California in the morning burns off by midday, leaving afternoons with intense, direct sunlight. West-facing rooms without film are at their hottest between 2pm and 5pm.
The Solution
Ceramic film is the premium choice for homes where view clarity and signal transparency are priorities. Non-metallic particles absorb heat without the mirror effect of metallic films.
Low-e retrofit film is specifically designed for older single-pane windows. It adds a low-emissivity layer that dramatically improves thermal performance — the most cost-effective upgrade for pre-1980 California homes.
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 historic or older home protection
Professional installers available in San Francisco
10–15 year manufacturer warranty
Installation Guide
The best time to schedule installation is in the morning, before the glass heats up. Hot glass causes the slip solution to evaporate too quickly, making it harder to position the film correctly.
Install time
30–45 min
Per window
$150–$400
Cure time
30 days