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Carolina Fire Rescue EMS Journal for a quick knockdown. If not, defensive operations with lots and lots of water for an extended period of time can be expected. These buildings may also have the floor joists fire-cut. A fire-cut is where the ends of the beams are cut at an angle inside the masonry wall to allow the floor(s) to fall into the building to maintain wall stability. We may also find bowstring trusses in the roof or arched roofs. Heavy timber construction happens today in some church sanctuaries using laminated lumber to get the heavy timber look, or assembly occupancies looking for a natural feel to their structures. As these buildings age as well, the modifications made include unprotected steel assisting the structural components already there. Some components may be removed as well, and that leads to structural collapse. This building is a true double-edged sword — it will take some time to get going and stay structurally sound for a long period of time, but when the fire takes over — heat generated by those timbers creates problems for any exposures in the area.
Type V – Wood Frame Wood Frame construction is the most familiar to all of us. A large part of our living, training
and learning occurs in these structures. It’s where we’ve “cut our teeth” and learned our trade, for the most part. Besides, residential structures outnumber everything else.The evolution here came from log cabins, to balloon-frame, then platform, and now lightweight construction. Small dimension lumber used for most frame houses. We now find wooden I-beams used in floor assemblies; although they are a strong weight-bearing material, they fail miserably under fire conditions. Documented cases show where houses are collapsing as the first-due apparatus arrives on scene. Now found are aluminum studs, laminated timbers, aluminum joist hangers, gusset plates and all kinds of truss assemblies. Be aware that air handling units are in attic spaces, adding to the dead load the trusses have to support — especially with fire burning underneath. Outer skins range from wooden grooved plywood siding, wooden siding with boards, Masonite® siding, aluminum or vinyl siding and finally brick. One of the most common size-up mistakes I hear is a “residential structure with masonry construction.” Masonry is a component — not a style of construction.The brick you see is a veneer — a single layer of brick for looks only. Although
there are some Type III - Ordinary construction single family buildings, knowing your buildings is vital to you and your crew’s lives. Now added to all this basic information are more changes: green construction with reusable materials, hybrid construction methods where several of the different types of construction are melded within a single building and construction methods that get lighter and cheaper. Add to that buildings
under construction, renovation and demolition — those are hazards on their own. With all this, how is it possible to keep up? Diligence and study — on duty and off — allows us to perform at our best. Knowledge is one of the best tools to have. This is only the tip of the proverbial iceberg. We all have to keep up with changes, and building construction is no different.Take time to really look at the buildings you protect, already standing and under con-
struction.The more we learn about the battleground we fight on, the better we will survive and pass on that information to the next generation of firefighters. Captain Coffey currently serves as one of the training officers of the High Point Fire Department. He has been an instructor with the NC Community College system and the Office of the State Fire Marshal since 1990. He can be reached at mpcoffey@hotmail.com.
Huntersville Fire Department Station 3
Garner & Brown Architects PA 1718 East Boulevard , Charlotte NC 28203
704•333•1051 www.garner-brown.com
North Carolina
2520 N. Wesleyan Blvd. Rocky Mount, NC 27804 Phone: 877-358-3473 Fax: 252-972-6846 sales@fireconnections.com www.fireconnections.com
South Carolina
725 Patrick Industrial Lane Winder, GA 30680 Phone: 800-965-6227 Fax: 770-868-4455 salesinfo@firelineinc.com www.firelineinc.com