By Gregory Havel
From our Firefighter I and II classes, we can recall the five “types” of建筑建筑that are used by the building and fire codes. These are based on the amount of combustible materials in the structure.
- Type V or wood frame has combustible materials anywhere in the structure, including load-bearing and non-bearing walls, floors, roofs, trim, and furnishings
- Type IV or heavy timber has combustible (but not easily ignitable) columns, beams, floors, roofs, trim, and furnishings; the load-bearing and exterior walls are masonry
- Type III or ordinary has combustible interior partitions and load-bearing walls, floors, roofs, trim, and furnishings, with exterior walls of masonry
- II型或不可燃料具有可燃的装饰和家具；可能具有可燃的不容纳分区墙。它可能具有可燃的阻塞以支撑橱柜，栏杆等
- Type I or fire-resistive is permitted combustibles as trim and furnishings
Today, these five建造types are no longer as clear-cut as they used to be because of the addition of lightweight and manufactured lumber materials, as well as the use of materials that were formerly found only in Type II or I建造。建筑法规官员认为这些是“混合动力”，并将根据使用的最可燃组件对它们进行分类。在结构钢上支撑的轻质桁架和木框建筑是一种混合体，将被归类为V型（照片1）。
(1)
The distinction between the building construction “types” is further blurred because of改建和翻新。通常使用符合建筑代码的最轻和最便宜的材料来重塑建筑物，而不是将新材料与原始结构中使用的材料相匹配。这导致将未受保护的结构钢引入II型和IV型建筑物中。以及制造的木材，I型咖啡师和木桁架的引入到了世纪以上的III型和V建筑物中（照片2）。
(2)
These “hybridized” buildings will no longer have thebehaviorthat we expect of them under fire conditions. The behavior of the fire itself will change: it is likely to spread faster and burn hotter than we might anticipate in a building of this age and type.
Rather than focusing on the type of construction that we see from the street upon our arrival, we need to focus on what we know of fire behavior in buildings, the probable routes of fire spread, and the probable speed with which it will spread.
The key points to this approach are:
- 可燃：承载负载的组件在多大程度上可燃？这些将在III型，IV和V型中找到。如果有疑问，我们应该假设承重的组件是可燃的。
- Lightweight: To what extent are materials “lightweight” I-joists, wood trusses, manufactured wood, or steel stud and truss assemblies? These can be found in any Type. If in doubt, assume that load-bearing assemblies are lightweight, with no inherent fire resistance.
- 混合动力：除了I类型外，任何类型的建筑物都可以是混合动力。如有疑问，假设它是一种杂种。
- 除了真正的IV型外，任何类型的结构中都可能存在隐藏的（空隙）空间。如有疑问，我们应该假设存在隐藏的空间，并且它们是相互联系的。
- 洒了: A true Type IV built since 1880 has an automatic fire sprinkler system. Any other type may have sprinklers. This note is a “must” on our preincident plan.
- 自1880年以来，额定的墙壁或地板天花板组件将存在于IV类型中。任何其他类型也可能具有这些。如果建筑物已经改建（没有建筑物？
Photo 3 shows the above information in a chart.
The key to using this approach is to use it inpreincident planning, so that we can best predict the paths of fire extension, the routes that the products of combustion will follow, and the best locations at which to stop the fire.
如果我们在一个陌生的结构中到达一场大火，我们没有preincidentplan, for the protection and safety of firefighters we must assume that the structure is:
- Combustible, of lightweight and manufactured materials, with hybrid components
- Surrounded with interconnected concealed spaces
- Unsprinklered
- Constructed without rated walls and floor-ceiling assemblies
As these assumptions are found to be not true, we will have more options available to us in fighting the fire.
当发现这些假设是正确的时，我们将有相同的选择来抗击我们在原始中使用的火灾事件行动计划, and we will have exposed our personnel to no unnecessary risk.
将本文作为PDF下载这里。
格雷戈里·哈维尔（Gregory Havel）is a member of the Town of Burlington (WI)Fire Department; retired deputy chief andtraining officer; and a 30-year veteran of thefire service。他是威斯康星州认证的fire instructorII, fire officer II, and fire inspector; an adjunct讲师在fire serviceprograms at GatewayTechnical大学;和安全Scherrer Construction Co.，Inc。Havel拥有圣诺伯特学院的学士学位；在设施管理和建筑建设方面拥有30多年的经验；并已在FDIC介绍课程。
MORE CONSTRUCTION CONCERNS
