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KYLE FLEMINGParticipantKYLE FLEMINGI agree with your answer and description DE Ed Shadoin. Firefighters must understand all aspects of roof construction to operate safely and effectively. Roofs are high-risk areas where fire can quickly compromise structural supports. Recognizing roof types and materials—like trusses, metal, or tile—helps assess collapse risk and identify safe ventilation points. Lightweight systems can fail rapidly under heat, increasing danger. This knowledge improves decision-making, reduces injury risk, and enhances overall operational safety during firefighting efforts.
KYLE FLEMINGParticipantKYLE FLEMINGDue to the roof being the most vulnerable part of a structure during a fire, a firefighter must be familiar with all the aspects of roof construction. Understanding roof types, materials, support systems, and potential collapse indicators helps firefighters assess structural integrity, choose safe ventilation tactics, and avoid hazardous areas. Roofs can conceal fire spread within voids or truss spaces, leading to sudden collapse if not properly evaluated. Knowledge of roof construction is essential for effective firefighting, ventilation, and ensuring firefighter safety on or beneath the roof.
KYLE FLEMINGParticipantKYLE FLEMINGThank you DE Ed Shadoin for your educated response. I agree. Pre-stressed concrete systems are more vulnerable to sudden failure because they rely on high-tension tendons to maintain strength. If these tendons are damaged by corrosion, fire, or improper tensioning, the structure can fail abruptly. Unlike traditional reinforced concrete, which allows more gradual failure, pre-stressed systems are less forgiving. Even minor cracks can lead to a loss of pre-stress and rapid structural compromise. Proper design and maintenance are critical to ensure safety.
KYLE FLEMINGParticipantKYLE FLEMINGDue to relying on high-tension steel strands to maintain their structural integrity, prestressed concrete systems may be more vulnerable to failure than ordinary reinforced concrete in fire conditions. When exposed to heat, these steel tendons lose strength and can rapidly relax or snap, causing sudden and complete failure of the concrete element. Unlike ordinary reinforced concrete, which may fail gradually and provide warning signs, prestressed systems can collapse without visible indicators.
Additionally, the tensioned steel is often under extreme stress, and once compromised by heat, the stored energy can be released violently. This makes prestressed concrete particularly dangerous for firefighters operating beneath or near these elements during a fire.
KYLE FLEMINGParticipantKYLE FLEMINGYour knowledge in this subject is superior, DE Ed Shadoin. I agree. Steel is a strong, durable, and versatile material with an excellent strength-to-weight ratio, making it ideal for efficient, long-span structures. Its resistance to pests, fire, and rot adds to its durability, and its recyclability supports sustainable building practices. However, steel can corrode without proper protection and offers poor thermal insulation, which may impact energy efficiency. It also tends to be more expensive and requires skilled labor for welding and assembly. Despite these challenges, its structural benefits make it a preferred material in many modern construction projects.
KYLE FLEMINGParticipantKYLE FLEMINGSteel offers several advantages in construction: it’s strong, lightweight relative to its strength, and allows for rapid, flexible design and assembly. It performs well under tension and compression and is ideal for large-span structures. However, in fire service contexts, steel has critical disadvantages.
While noncombustible, it loses strength rapidly when exposed to high heat, potentially failing at temperatures as low as 1,100°F. Steel also expands when heated, which can cause connections to deform or structural elements to push outward, leading to collapse. Additionally, unprotected steel lacks inherent fire resistance and requires insulation or fireproof coatings to meet safety codes. Firefighters must recognize that steel-framed buildings can appear stable yet collapse without warning under fire conditions.
KYLE FLEMINGParticipantKYLE FLEMINGI agree DE Ed Shadoin, firefighters must understand building collapse mechanisms, especially in masonry construction, to operate safely and effectively. Masonry materials are strong under compression but weak under tension, making them prone to sudden failure during fire or structural compromise. Fire, water, and added loads can quickly weaken these structures. Recognizing signs like cracks, bulging, or spalling helps firefighters anticipate collapse and adjust tactics. This knowledge supports safer decisions in entry, ventilation, fire attack, and rescue, ultimately protecting crews and saving lives.
KYLE FLEMINGParticipantKYLE FLEMINGFirefighters must understand the mechanism of building collapse in masonry construction because these structures can become highly unstable under fire conditions. Masonry, especially unreinforced, is brittle and prone to sudden failure when exposed to heat, water, or structural stress. Fire can weaken mortar joints, cause thermal expansion, and lead to cracking or wall separation. Parapets, veneer walls, and freestanding sections are particularly at risk of collapsing outward, endangering crews operating nearby. Recognizing early signs of collapse—like bowing walls or falling bricks—allows firefighters to adjust tactics, avoid hazardous zones, and operate more safely. This knowledge is critical for making informed decisions during firefighting operations and ensuring firefighter survival.
KYLE FLEMINGParticipantKYLE FLEMINGI agree that wood has many disadvantages in construction, including its tendency to warp, swell, or shrink due to moisture and its natural defects like knots, splits, and insect damage. That is unfortunate scenario that you described DE Ed Shadoin, because of the collapsing of the building’s roof overhead. Especially with the older homes in South Florida, keeping a keen eye on the construction and the sound the building is making while fighting fire, search and rescue, and salvage & overhaul are very important for the safety of the crew.
KYLE FLEMINGParticipantKYLE FLEMINGSome of the disadvantages to wood construction are high flammability, susceptibility to rot and insect damage, structural weakness over time, and vulnerability to moisture-related warping or decay.
Furthermore, I have not personally dealt with a work-related call pertaining to wood-construction other than knowing the fire spread throughout attics due to open space between apartments in a multi-family complex. Due to the possibility of high flammability, as compared to other materials, there could be some reignition of fires if not properly searched with overhaul. Sometimes you might be laying in your bunk after the fire, and having to return to the residence to put out a fire you have already fought due the wood construction of the trusses in the attic. Always be vigilant when a fire could possible spread to other living quarters.
KYLE FLEMINGParticipantKYLE FLEMINGI agree with this statement. It accurately describes the common types of building movement—settlement, heaving, and lateral displacement—and explains that some movement is expected in all structures after construction. Foundation settlement is indeed the most common, and recognizing its symptoms is essential, especially for fire service personnel. Signs such as distorted frames, sloped floors, cracked walls or glass, and malfunctioning doors or utilities are critical indicators of potential structural instability. Understanding these movements and their effects helps firefighters assess building safety and make informed decisions during emergency operations, reducing the risk of injury or collapse.
KYLE FLEMINGParticipantKYLE FLEMINGBuilding settlement refers to the downward movement of a structure’s foundation, which can compromise structural integrity and pose hazards during fireground operations. There are two primary types of settlement:
– Uniform Settlement: Occurs when the entire structure settles evenly. This type is generally less concerning, as it maintains the building’s alignment and structural integrity.
– Differential Settlement: Happens when different parts of the structure settle at varying rates, leading to misalignment and potential structural issues.
Symptoms of settlement include distorted building frames sloped floors, cracked walls and glass, improperly functioning doors and windows, and damaged building utilities and systems.
Firefighters must be vigilant for these signs, as they can indicate compromised structural stability, increasing the risk of collapse during fire incidents. Recognizing these symptoms is crucial for ensuring firefighter safety and effective incident response.
KYLE FLEMINGParticipantKYLE FLEMINGI agree with the explanation, DE Shadoin. It clearly distinguishes fire partitions, enclosure walls, and curtain walls based on their purpose, fire resistance, and construction. Fire partitions subdivide interior spaces and don’t require full continuity or high fire ratings. Enclosure walls are designed to prevent vertical fire spread and are used around shafts and stairwells, requiring higher fire ratings. Curtain walls are non-load-bearing exterior walls used in high-rise construction, primarily for environmental control, not fire protection. The material distinctions are also well noted.
KYLE FLEMINGParticipantKYLE FLEMINGFire partitions, enclosure walls, and curtain walls serve different functions in building design and fire safety.
Fire partitions are interior walls designed to limit the spread of fire within a building. They typically have a fire-resistance rating of at least one hour and separate spaces like corridors, dwelling units, or tenant spaces. They may extend from floor to ceiling or to a fire-rated ceiling assembly.
Enclosure walls are fire-rated walls used to enclose vertical openings such as stairwells, elevators, or shafts. These walls usually require a higher fire-resistance rating (often two hours) and must form a continuous barrier from the floor to the roof to prevent fire and smoke from moving between floors.
Curtain walls, in contrast, are non-load-bearing exterior walls, often made of glass and aluminum. They are primarily architectural and do not inherently provide fire resistance unless specifically designed and rated to do so. They must be properly sealed to prevent fire spread.
KYLE FLEMINGParticipantKYLE FLEMINGFor egress, the fire service specifically focuses on enclosed exit stairs and protected stairways. These stairs are designed to provide a safe, fire-resistant means of escape during emergencies. They are typically constructed with fire-rated walls and doors to prevent the spread of fire and smoke into the stairwell, ensuring occupants have a clear, protected path to exit. Materials used are usually noncombustible, like concrete or steel with fireproofing. These stairs must be continuous, unobstructed, and meet minimum width and headroom requirements to allow for quick and safe evacuation. Open or unenclosed stairs are generally not permitted for egress because they expose occupants to hazards. Firefighters rely on these protected stairwells for both evacuation and operational access during incidents.
