A home automation system automates your whole house, triggering events and routines involving light fixtures, security components and the heating/cooling system based on the time of day, temperature or any other condition that you select. For instance, when a sensor detects a vehicle in your driveway, your home automation system could turn on your lights.

An automation system controls a collection of "subsys-tems." A subsystem is a system that—even when operating by itself—provides benefits to a homeowner. Common subsystems include lighting, security, entertainment and heating/cooling systems, as well as devices like motorized drapes and basic appliances. A home automation system puts two or more subsystems under the control of one central controller, so that the press of one button can issue several commands to a variety of different electronic products.

A popular example: Pressing an "Away" button on a keypad might arm the security system and set back the thermostat to an energy-saving level. Pressing the "Home" button does the reverse.

Central Themes
Most whole-house systems consist of two key components: a CPU (central processing unit) and user interfaces. The CPU, normally hidden in a closet, basement or other inconspicuous place in the house, serves as the brains of a home automation system. Subsystems, like lighting controls, communicate with the automation system via the CPU. Homeowners use interfaces such as keypads, touchscreens, handheld remotes or a PC to interact when necessary with the various systems linked to the automation CPU.

The similarities of home automation systems stop here. Each automation system differs in its degree of intelligence, ease of programming, level of flexibility, intuitiveness of operation, communications media employed, price and other features.

To help you make sense of the scores of viable options, we’ve divided the current fare of home automation systems into two very broad categories: moderate and high-end. Of course, you should not ignore the ultra-affordable option of a simple pre-wire. Sophisticated structured cabling systems can be installed for less than $1,000 in a 2,000-square-foot home, and they provide tremendous benefits.

Moderate Systems
This category includes systems that typically range in price from $1,000 to $3,000 (not including installation) and offer basic control features for two or more integrated subsystems—lighting and security, for instance. Dial-in access to the home automation system, which allows a homeowner to control integrated components from any touch-tone phone, is another standard feature among mid-priced systems. With systems that fall in this price range, it’s also reasonable to expect such amenities as flood sensors, voice annunciators, dialers that automatically call a monitoring station or a homeowner’s pager in an emergency, and possibly a keypad with a built-in intercom.

Often missing from moderately priced systems are the controls that allow sophisticated dimming of lights, and the ability to integrate components such as audio/video gear.

The modular security system from Caddx starts at under $500 and lets homeowners add such functions as climate and lighting control.

User interfaces in this category might consist of keypads, standard telephones and/or a PC. Often, the simplicity of the user interface helps keep these systems inexpensive.

Mid-range systems install much like security systems, which keeps the installation fees under control. In fact, many moderately priced home automation systems started out as advanced security systems. The added elements that make these systems "automation worthy" are extra inputs and outputs for integrating a programmable thermostat, and perhaps an X10 interface for communicating with lights and appliances over the home’s AC powerlines.

Generally, the moderate systems do not interface with entire subsystems—HVAC controllers and sophisticated lighting, for example. Rather, they tend to connect directly to the appliances to be controlled—lights, thermostats, pool pump and so on. This method of integration minimizes elaborate programming requirements, which makes up a large chunk of the expense of high-end systems.

The modest capabilities and price tags of moderate systems don’t undermine their reliability. Companies like Home Automation Inc. and Apex have, for years, manufactured top-notch mid-range systems that have been installed in thousands of houses. Also, such well-known manufacturers as Napco, Ademco, ITI, DSC and Caddx offer home automation systems that are as sturdy as the security systems for which they’re famous.

Perhaps the biggest benefit of moderately priced systems is that they can be installed unadorned at a very low cost. Homeowners can then add bells and whistles later at their own expense.

High-end Systems
High-end whole-house systems typically range in price from about $5,000 to more than $50,000 (not including installation). Most come loaded with customized—or customizable—functions and top-of-the-line user interfaces. What distinguishes the high-end systems from their more affordable counterparts is that they can integrate virtually any subsystem into a seamless home control network—not just security, lighting and HVAC, but also entertainment, telecommunications, and sprinkler and pool/spa systems. High-end systems can do virtually anything, but configuring and installing them doesn’t come cheap.

Sleek touchscreens and A/V integration put Panja products ($5,000-$10,000) at the high end of the automation market.

Some high-end systems are sold with the subsystems themselves. Lightolier, Lutron Electronics, LiteTouch, Smart LLC and Vantage, for instance, are famous for their sophisticated lighting controllers, but they all offer other key components for a complete home automation system. Panja and Crestron, on the other hand, make systems with optional lighting control "modules." Still others, like Smart Systems Technologies and Leviton, offer moderate-to-expensive (starting at $5,000) fully integrated systems that include security, lighting, temperature and audio control in one package.

Effective whole-house lighting control with sophisticated dimming capabilities often contributes the biggest expense to a high-end home automation system. Integrated control of audio/video gear is another costly component. The advanced equipment required to tackle lighting and A/V normally demands many hours of programming and installation by an experienced home systems integrator.

Because of all the different features and functions high-end systems include, users need sophisticated interfaces to simplify control. The preferred interface of most high-end systems is a touchscreen, because several "pages" of "buttons" can be designed specifically for each household. The LCD technology of touchscreens is expensive, and so is the programmer’s time for creating designs conforming to a family’s needs.

Other interesting interfaces that have appeared recently include keypad stations with built-in temperature sensors and intercoms. Panja and Crestron have both introduced these types of next-generation user interfaces, and you can expect other manufacturers to follow suit.