Energy · 7 min · 2026-05-01
Energy savings from exterior shade
How projection, fabric openness and louver angle cut solar heat gain before it hits the glass.
What actually moves the bill
A 10–13 ft awning projection on west glass, a 3–5% overhead blind on a conservatory, or closed Helio blades at solar noon all reduce HVAC load. Use the solar heat-gain calculator at /tools/solar-heat-gain with the product specs and the pergola cost tool for budget.
Questions people ask
- Is exterior shade better than interior blinds?
- Yes for heat. Interior treatments manage glare after the energy is already inside. Exterior systems intercept radiation first.