Description

Just about any window attachment that is adjustable can be automated: shades, screens, awnings, shutters, and draperies. Automation includes motors, sensors, controls, and timers. Motors can raise-and-lower, tilt, or both. Both controls and power can be wireless, the former using radio frequency technology and the latter using battery technologies. Today’s window attachment motors and batteries are typically concealed and protected in the roller tubes of the attachment and operation of the newer motors is approaching “noiseless" operation.

Powering window attachments

There are three options for powering motorized attachments: battery (direct current or DC), outlet (may be DC or alternating current— AC), and inwall (AC). Battery power has the advantage of being wireless and not involving an electrician, but it is better suited to smaller or lighter window attachments. And even with long-life lithium batteries, periodic replacement is required (rechargeable batteries powered by a small solar photovoltaic panel are becoming available for exterior window attachments).

Outlet power is convenient because an electrician does not need to wire the attachment. In new construction, outlets can be concealed along the margin of the window or more typically up at the top of the window behind a valence or the head cassette of the attachment. “Fishing” of lighter gauge DC wiring is generally easier than larger-gauge AC wiring. DC motors (low voltage) require a transformer to step down and convert the AC house current. In general, DC motors are better suited to low to medium lift requirements.

Inwall power is AC house wiring direct to the motorized window attachment. Inwall power is best accomplished when wall cavities are open, during construction or major renovation. AC motors are well-suited to heavy lifting and can even service multiple window attachments.

Controlling motorized window coverings

When motorized window coverings are controlled by sensors, timers, or programs, the system is automated. Controls for motorized attachments can be either individual or grouped. Options include everything from battery-powered, hand-held remote control to mesh network, smart phone app-driven systems to full integration with a home's automation system.  Programmable operation can be based on light intensity or temperature. Wind sensors can be included in exterior window attachment systems, which will then automatically retract when high winds threaten exterior attachments. Manufacturers of window attachment automation systems give detailed guidance on all the options and specifications for motors, power sources, and controls based on the type and size of window attachments.

New tubular motors like the one shown in this photo fit inside the axle tube around which the shades or awning is wrapped. These tubular motors are quite powerful, quiet, and durable. Tubular motors are capable of as much as 200 pounds of lift!
Photo: NuImage Robusta Awning by Futureguard, Auburn ME

Overall Thermal Performance

Each adjustable window attachment’s thermal performance can be improved by optimal operation. Several studies (see References) have shown significant improvement in both the thermal performance of adjustable window attachment operation as well as reduced lighting energy consumption when automation is employed. Savings can be achieved both from remote handheld user operation of motorized attachments asnd from automated operation employing sensor-activated window attachments. 

Key Benefits

• Ease of operation, convenience
• Continued optimal operation during absence (security)
• Safety (no cords)
• Energy savings

Key Drawbacks

• Cost
• Learning curve for programming
• Size limitations
• Not available on all attachment types

Aesthetics

• Clean installation (hidden motors, no cords)

Tips/Cautions

• Batteries must be changed every 12 – 36 months (if battery-powered)
• Particularly for large exterior attachments, wind sensors are a good idea