How Custom Drapery Can Lower Your HVAC Energy Costs

Energy Saving

by Jeanette Chasworth of The Color Whisperer

Most homeowners focus on their HVAC system when trying to reduce energy costs, but windows are one of the largest sources of heat gain and loss in a home. In fact, untreated or poorly treated windows can significantly increase the load on your heating and cooling system.

The Role of Drapery in Insulation

Drapery can act as an additional insulating layer at the window, but only if it is properly designed. Many store-bought panels are either unlined or use low-quality, thin linings that provide minimal thermal resistance. Without a substantial lining—such as thermal or blackout materials—the fabric does little to slow heat transfer. As a result, solar heat gain in the summer and heat loss in the winter pass through the window area with minimal reduction.

Why Full Window Coverage Matters

Coverage is another critical factor. Most ready-made panels are not wide enough to fully span the window opening when closed, which leaves gaps between panels or at the edges. These gaps allow for convective airflow, meaning conditioned indoor air escapes while unconditioned outdoor air enters. Even small openings can reduce the effectiveness of the barrier and increase HVAC runtime.

Installation Details That Affect Performance

Proper installation also plays a role. Custom drapery often includes returns—where the fabric wraps back toward the wall—helping to limit air movement at the sides of the window. When combined with adequate fullness (the correct fabric-to-window width ratio), this creates a more continuous barrier that reduces both radiant heat transfer and air leakage.

Potential Benefits for HVAC Efficiency

When drapery is correctly specified and installed—with appropriate lining, full coverage, and sealed edges—it can help stabilize indoor temperatures and reduce the frequency and duration of HVAC cycles. The result is improved energy efficiency, increased comfort, and less strain on your system over time.

A Whole-Home Approach to Energy Savings

If you’re evaluating ways to improve efficiency beyond the mechanical system itself, window treatments are a practical area to consider. While HVAC equipment plays a major role in home comfort, addressing heat gain and loss through windows can also contribute to overall energy performance.

Have Energy Related Questions?

Contact the energy experts at Air-Tro for even more energy saving tips at 626-357-3535. We’ve been keeping California comfortable since 1969.