Why This Matters
The afternoon sun angle in Southern California between June and September is low enough to drive direct solar radiation deep into west-facing rooms. Standard window treatments block the view; film blocks the heat.
Near South Hall in Berkeley, west-facing windows at low afternoon sun angles drive the highest interior temperature increases. This is especially problematic for home office installations, which glare control and uv protection are critical for home offices with screen-facing windows.
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
Residential window film is the most targeted solution for solar heat gain: it addresses the problem at the source — the glass — rather than compensating with more cooling.
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.
Retrofits existing glass with a low-emissivity coating for improved thermal performance.
Climate & Solar Performance
Properties near South Hall in South 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 home office protection
Professional installers available in Berkeley
10–15 year manufacturer warranty
Installation Guide
A qualified installer will assess your window orientation and glass type before recommending a film grade. They'll identify your highest-gain exposures and match the right film to each.
Install time
30–45 min
Per window
$150–$400
Cure time
30 days