Structured Home Wiring

Future Wire your Smart Home:
From planning to installation for
audio, home theater, security,
surveillance & home automation.

Planning a Security System / Burglar Alarm

The first step when installing any alarm system is to determine what you will install and where. Below is a typical floor plan from a home builder that has been marked up to indicate where alarm components will be installed. These simple plans are the type that builders normally provide to people looking to build a new home and can sometimes be found on the builder's web site. Marking up a copy of these plans is a good place to start to determine how many window & door sensors and motion detectors you will need to protect the entire home.

Sample Alarm Wiring Plan

P: Main Alarm Panel
K: Keypad
Input Devices
M: Motion Detector
D: Door Sensor
W: Window Sensor
G: Glass Break Sensor
L: Liquid/Water Sensor
24 Hour Input Devices
F: Fire/Smoke/Heat Sensor
Output Devices
H: Horn/Siren
S: Strobe Light
Alarm Security Wiring Plan First Floor
Alarm Security Wiring Plan Second Floor
Alarm Security Wiring Plan Basement

The first major decision is to determine if you want to have sensors for every window in the home or are motion detectors good enough to provide coverage. A quick look at these floor plans shows that wiring sensors for every window more than doubles the amount of wires that you will need to run.

A typical entry level panel is limited to 8 zones. Even higher end panels need expander cards to support more than 8 zones. Even if you have more than 8 sensors you can still use an 8 zone panel. You will just need to wire multiple sensors to a single zone. When a zone with multiple sensors is tripped, you will not be able to determine which sensor is the cause. Also, if there is a fault/error with a multiple-sensor zone it will be more difficult to diagnose.

Here are some examples of 8, 16, & 32 zone setups.

8 zone: - Assumes Fire detectors are handled separately
  • Living Room Motion Detector
  • Family Room Motion Detector
  • Dining Room Motion Detector
  • Basement Motion Detector
  • Front Door
  • Back + Garage Door
  • Dinette Glass Break Sensor
  • Water Sensor
16 zone: - The above 8 zone layout plus window sensors (multiple windows per zone)
  • Dining Room Windows
  • Living Room Windows
  • Family Room Windows
  • Kitchen/Laundry Windows
  • Owner's Bedroom/Bathroom Windows
  • Bedroom 2 Windows
  • Bedroom 3+4 Windows
  • Basement Windows
32 zone: - With 32 zones, every sensor indicated in the floor plan above will have its own sensor.

There are other considerations when combining sensors into a single zone. Alarm systems can be activated with some zones disabled. For example, if you activate the alarm at night when you sleep you want the doors and windows protected, but you do not the motion sensors active. You probably want the motion sensors disabled so that you can walk around the house without setting off the alarm. Therefore, you should not combine the window & motion sensors from the same room into a single zone. During a hot summer night you may want to leave the windows in your room open, but not any of the downstairs windows. Again, these windows would need to be in separate zones so that you could leave upstairs windows open but have the downstairs windows protected.