Solar Screens, Film or New Windows in Austin?

In Austin, the window problem is mostly heat coming in. A west-facing bedroom on a July evening can stay hot hours after sunset because glass let in a whole afternoon's sun. There are three main fixes, at very different price points.

The number that matters: SHGC

The Solar Heat Gain Coefficient on a window's NFRC label measures how much solar heat passes through. Lower means less heat. Existing clear single-pane or early double-pane glass has a high SHGC, and modern low-E glass designed for hot climates has a much lower one. Exterior shading lowers the effective heat gain even more, because it stops sunlight before it reaches the glass.

Option 1: exterior solar screens

These are mesh screens mounted outside the window that block a large share of sunlight before it hits the glass.

• Cost: the lowest of the three options.
• Pros: very effective on west and south windows, no construction, and easy to remove or replace.
• Cons: they darken rooms, change the exterior look, can reduce winter solar warmth, and some HOAs regulate them.
• Best for: rentals, budget-limited upgrades, and problem windows in otherwise sound frames.

Option 2: interior window film

These are thin films applied to the glass.

• Cost: low to moderate.
• Pros: invisible from outside (historic-district friendly), with options for glare and UV control.
• Cons: less effective than exterior shading because heat is absorbed at the glass. Check with the window manufacturer, because some films can void warranties or stress certain glass types.
• Best for: historic homes, HOAs that dislike screens, and glare control.

Option 3: low-E replacement windows

New windows with low-SHGC glass, better frames and proper installation.

• Cost: the highest. HomeGuide's national guide lists $4,500 to $22,500 for 10 to 15 windows.
• Pros: they solve heat gain, drafts, failed seals and operation problems at once, and they last for decades.
• Cons: the highest cost, and they need an express permit in Austin for size-for-size replacement. In historic districts, original windows may be protected.
• Best for: failing windows, single-pane aluminum units, or a planned exterior renovation.

Side-by-side

Historic homes

In Austin's local historic districts, exterior changes to contributing properties need review, and original windows are among the most protected features. Interior film or restoration with interior or exterior storm windows is often the easiest path. See Hyde Park.

ECAD and selling

For Austin Energy-served homes 10 years or older inside city limits, the ECAD energy audit is shared with buyers. Window and shading improvements can show up favorably on the audit.

Rebates

Check Austin Energy's residential rebates and whole-home efficiency programs before buying. Programs change, and some have included shading measures. Federal window credits ended after 2025.

A smart order of operations

1. Treat the worst west- and south-facing windows first.
2. Add attic insulation and air sealing.
3. Replace windows when they're failing or during a renovation.
4. Right-size HVAC after envelope improvements. See our HVAC guide.

Installation tips

• Get solar screens custom measured so they fit tight, since gaps let in light and bugs.
• Ask about fire-egress requirements for bedroom windows. Screens should be removable.
• Check HOA rules on screen color, as some subdivisions limit frame colors.
• For replacement windows, ask for the NFRC label values in writing for each window type.