I think I saw a program on Modern Marvels Doomsday something recently that explained that these wireless systems are extremely easy for experienced computer hackers to use to get into your WAN. Is this true? Out clients allow us to install what we will with the tacit understanding that their security is paramount.

RESPONSES TO A. PENNY:
KEITH LANE: The cost of running wire for sensors in buildings is 50%-70% of the cost of the sensor. Wireless communications could eliminate much of that cost. As the wireless technology improves and the costs of the individual points comes down, the feasibility and cost of going wireless will continue to improve.

JIM KOHL: Wireless does merit careful consideration in new construction. It is a misconception to think that wireless hardware automatically carries a high-cost premium — and any differential can often be offset by labor savings. Accounting for the labor to relocate sensors can make total cost of ownership comparable or even lower than using wired controls.

TIM KUHLMAN: This all depends on the type of building, building construction methods and how far along a building owner has come in integrating a building management system with the rest of the IT system. In a single occupant building the IT group has most likely planned for a pervasive wireless network. However, in a multi-tenant building it isn’t practical to have a building management system supported by the local tenants. In this case a wired solution is more practical.

STEVE TOM: While I think the cost advantage of wireless controls is much greater in a retrofit application, they can be less expensive to install in new construction as well, particularly when you’re using battery powered zone sensors or thermostats. Higher up the control chain you need external power for the controller and actuators, and pulling communication wires does not usually add much additional cost over the expense of providing power wiring. If you can run the device on a battery, however, there is no wiring required and the installation cost can be significantly lower.

While wireless has some advantages in existing structures, in a new building would it not be less expensive to install a digital control wire between fixtures? The cost of installing cable must surely be less expensive that wireless control systems.