January 2000
Revised February 2004 Home Automation Options for Existing Houses: "No New Wires" Solutions  There is no doubt that the needs of today's consumers for information technology in their homes have dramatically increased in the last five to ten years. People everywhere are dealing with a much greater volume of information than ever before and they need the capabilities to process it much faster than ever before. This acceleration shows no sign of slowing—quite the contrary.
The demand for home automation services to serve these needs is significant. A random national survey of 1,000 households conducted by the Consumer Electronics Manufacturers Association (CEMA) in Arlington, Virginia found that nearly three-fourths of American adults know about home automation systems and a majority are interested in owning products that use technology to manage a wide range of tasks. The best choice for builders of new houses seems to be installing upgraded wiring while they have the chance during construction. Despite the fact that installing upgraded wiring in existing structures is generally cost-prohibitive, home automation features, especially those that deal with communications, can be added to existing homes. Three types of products are currently available for retrofit home automation upgrades: power line carrier, infrared, and radio frequency. In addition to these three options, there is a phone line network being developed by the Home Phone Network Alliance (HomePNA). With these products, remodelers, owners of single-family houses, and managers of existing rental apartments can opt to incorporate home automation features to control security, entertainment, lighting, windows, lawn sprinkling, and energy management. The most common method is power line carrier (PLC) systems. PLC transmits coded communications signals over the same wires that are used for AC power in a house. PLC products from the X-10 company are widely used examples. While X-10 is a trademarked name and a proprietary communications protocol, many companies make X-10 compliant products. Just about any type of appliance or light that uses AC power can be remotely turned on or off by using either external modules that plug into an outlet or modules that fit inside an electrical box. An X-10 control panel might have six switches and several remotely controlled devices to turn on or off lights or appliances. Also available are interface cards that will fit into a computer to work with control software. A common problem with some versions of this technology, however, is electrical noise on the power line. Some manufacturers say they have found a way around this by automatic gain control circuitry. But sometimes this circuitry causes a loss of sensitivity to command signals. Other PLC communication products for home automation applications are less likely to have errors while communicating and offer higher data rates than X-10, so more complicated functions can be controlled. These products use a technique called spread spectrum. One variation from Intellon conforms to the Consumer Electronics Bus (CEBus®) standard of the Electronic Industries Association. The other variation is from Echelon. The company sells its proprietary method directly to manufacturers. In addition to PLC systems, there are wireless devices that can also work in existing houses. Infrared (IR) is a wireless method used for short-distance remote communications, such as controlling entertainment products or connecting a computer to a printer. But IR has limitations, since the signals cannot go through walls or around corners. The wireless method getting more attention in recent years is Radio Frequency (RF) transmission. RF has been used for wireless home security systems and for some other products that transmit signals over short distances in a house. Wireless vendors are working on a standard to make radio transmission surpass the speed of landlines. Wireless networks are being used for computer local area networks and transmission of audio files to digital audio players. The use of affordable wireless systems is increasing in home automation. Also coming onto the home scene are digital subscriber lines (DSLs) that could give new life to the copper wire that telephone companies have in place all over the country. DSL lines, which use existing copper wires, would give homeowners increased speed of access to the Internet in the same way that high-speed T1 lines give to businesses. Homeowners' demand is significant for these types of devices. A national study from Parks Associates, "Networks @ Home: Multiple-PC Households," found that RF-based networking ranks just ahead of phone line networking as a first choice in "no-new-wires" data networking. Power line networking is a strong second choice for most multiple-PC households, according to the survey. With any developing technology, it is usually a good idea for remodelers or homeowners to consult with several sources of information to determine what course of action is best for their situation. A good place to start is the ToolBase Hotline at (800) 898-2842. | 
