Alarm System Design Basics

When someone decides to install a burglar alarm system, there are two motivations to be considered:

  • Property Protection (primarily for use when home is not occupied)
  • Personal Protection (for use when home is occupied)

Property protection

Property protection is the easier of the two types of protection to evaluate. It is primarily “objective” as it takes into consideration the operating statistics of burglaries and the observed methods of operation of burglars.

90% of burglars gain entrance through unlocked doors and windows. Once inside, the first action a burglar takes is to open an exit door to ensure he can escape quickly in the event he is “discovered” during the burglary. After he has made sure that the can get out easily in the event of detection, the burglar will move throughout the home “scouting” for the best items to take. Favorite areas include master bedrooms and media rooms.

A good basic strategy to design a system to protect your property is to protect:

  • All doors that go outside the house
  • Interior door to garage (if connected to the house)
  • Interior motion detector or glassbreak detector
  • Covering stairways that go between different levels of the home 
  • Covering hallways that lead to bedrooms
  • Covering daylight basement areas

Motion Detectors are used to prevent movement from one area to another.  If you have indoor pets (dogs or cats) that are left inside when you are away, great care should be used in both the placement and number of detectors. Motion detectors cause over 90% of false alarm activations and should be used very sparingly. If you cannot use motion detectors because of your pets, it is good to protect one or two interior doors to prevent burglars from having free access and movement throughout the house.

Glassbreak Detectors are sometimes used in areas with a large number of windows. Pets do not affect the glassbreak sensors but it is important to remember that the window must be broken; opening the window does not trigger the system. A glass break sensor will cover a 25-foot area of window but will not cover more than one room. It is also not effective if there are curtains or blinds covering the windows.

Property protection serves to prevent successful burglary attempts. By triggering the alarm sirens, the burglar usually leaves the premise immediately and loss is minimized.

Personal protection:

Personal protection is more difficult to evaluate because it is a “subjective” analysis. Each person has their own level of protective comfort, which is a product of their experience. A person who has been burglarized will have different criteria than one who has not. Men and women often have different levels of protective comfort and security needs. The challenge for the burglar alarm system designer is to design a system that gives the homeowner a system that makes them feel safe, while still keeping the system easy to use as well as being in a comfortable price range.

It is very difficult to give good design advice for personal protection without seeing the home and talking to the homeowners. My experience over the years has been that salesmen (who are paid on a commission basis) tend to sell the customer more protection than they need, creating a greater possibility of false alarms, difficulty of use and unnecessary expense.

All major alarm system manufacturers provide emergency features built into the alarm keypads that operate the system that allow the homeowner to alert the central monitoring station to Emergency Police, Emergency Fire and Emergency Medical  conditions.