Understanding Building Construction is a crucial part of firefighter safety. New Jersey utilizes (5) five types of construction using a Roman numeral format. They are;;
- Type I Fire Resistive (Highest)
Type II Non Combustible
- Type III Ordinary
- Type IV Heavy Timber
- Type V Wood Frame (Lowest)
The higher the construction type the greater its fire resistance.
Type of construction is further categorized as Protected Construction, Type A and Unprotected Construction, Type B. It’s important to note that this designation applies to the “passive” fire resistance of a building, i.e. the use of concrete, gypsum or spray applied fire resisting materials to protect structural elements and not whether or not a building contains active fire protection systems such as fire sprinkler, fire standpipe or fire alarm systems.
For example a Type IA Building would be of Protected Fire Resistive Construction affording a (3) Hour Fire Resistance rating of the structural frame. It should be noted that most single and two family homes are constructed of Type VB unprotected wood frame construction, the lowest, which carries a fire resistance rating of (0) zero hours. In general the permissible height and area of a building is limited by the occupancy classification and the type of construction.
Information regarding a buildings construction type is available from the jurisdictions building or construction department. Firefighters can use this information for preplanning in understanding how a building may perform under fire conditions.
Additionally we must be keenly aware of the methods and materials used in the construction of a building. Firefighters must be ever vigilant of unprotected lightweight and truss construction, a hazard to all firefighters. Numerous firefighters have been killed or injured where lightweight and or truss construction failed under fire conditions. It’s important to keep in mind that these construction methods are used in commercial and residential buildings.
The New Jersey Uniform Fire Code provides for the posting of a standard “Truss Insignia” for buildings employing truss construction, the exception being one and two family dwellings. If truss construction is known to exist in a building that is not appropriately marked this should be promptly referred to the local Fire Official/Fire Marshal for corrective action.
Some municipalities have also undertaken a program to indentify lightweight construction in one and two family dwellings by way of a special insignia applied to the cover of electrical meter enclosures. Check with your local Fire Official/Fire Marshal to find out if such a program exists in your community.
Here are two documents for your reference. Post them in your firehouses.