A Commonsense Approach to Building Construction

BY MICHAEL J. LOPINA AND TOM TULIPANO

Although much has been written on building construction and fire behavior, there seems to be a growing debate on when we should go in or stay outside the building on the fireground based on building construction and fire behavior. We want to be aggressive, interior attack firefighters, but certain modern features such as lightweight construction cause us to pause and take note of what we are getting into. It is not our intent to get into whether you should or shouldn’t go inside; it is to make you aware of what to look for before making that decision. Are you going into a “routine” room-and-contents fire in a one-story 25-foot × 50-foot frame “bungalow” (photo 1) or into a frame that has been added onto several times, resulting in numerous void spaces, which, once involved in fire and allowed to burn unchecked, can trap or kill firefighters (photo 2)?

(1) A typical “bungalow”-style house; bungalows can be of ordinary (Type III, such as this one) or frame (Type V) construction. A unique hazard associated with an enclosed porch such as that seen here is that failure of the picture window from the living room to the porch can cause fire to get behind and trap crews entering the front door. Recognize this hazard during your size-up. (Photos by Michael J. Lopina unless otherwise noted.)

(2) This small ranch on a slab (identified by the absence of window wells around the house) has been added onto several times, almost tripling the size and adding numerous void spaces. Such add-ons have a history of trapping and killing firefighters.

SIZE-UP

Another aspect of size-up and building construction is identifying what you are looking at. You must understand what you have before you know what you can do. A good size-up should include, at the very least, the following: height (two-story, and so on); construction type (wood-frame, ordinary, lightweight); dimensions (25 × 50); direction of apparatus; fire location, if known (fire on the second floor, smoke from the rear); and action.

Departments have used this type of radio size-up for many years to “paint” a quick, but descriptive, picture for all incoming companies and the dispatch center. It takes 15 to 20 seconds to put it together: “Engine 1 is on the scene. We have heavy fire on the second floor of a two-story frame 25 × 40. We are northbound leading out.”

This identifies the first company on the scene and tells the incoming truck companies what type of ladders they will need for second-floor windows and that vertical ventilation is needed for a top-floor fire. The radio report also tells other companies what type of fire conditions and how much fire they may be faced with [25 × 40/3 = 333 gallon-per-minute (gpm) fire flow if the second floor is fully involved].

Finally, the first engine reported its direction of travel. This tells other incoming companies which way to approach, especially the first-due truck so it can take the front of the building. Direction of travel given in a size-up seems to be exclusive to the Chicago Metro area, but it is an integral part of the size-up process, as it tells subsequent responding companies which way to approach the fire scene. This is justified further in that many of Chicago’s side streets are one way and one lane wide. By letting other companies know it is “northbound,” the first-in engine has set the groundwork for the remaining apparatus to position themselves accordingly and properly.

It is also common practice for the first engine to pull past the fire building to give the front of the building to the “ladder” company. If this is done and the direction of travel is not given, there is potential for the truck company or next-arriving engine to come in from the opposite direction and not be able to position properly or, worse, block the first engine from finishing its leadout. Once regarded as “just something Chicago does,” including this information has been recognized as a way to maximize use and reduce congestion of initial-arriving apparatus and has been integrated into many suburban Chicago departments’ size-ups.

Furthermore, we report that a structure is “a wood frame” on arrival, but is saying just “wood frame” enough? We know that Type V identifies balloon or platform-frame construction, which may include lightweight materials. There are very easy clues that tell the difference between platform and balloon-frame construction. Balloon frames were homes built prior to about 1940 in which the wall studs run the whole height of the building, creating a void space from foundation to attic. This is also the reason the windows in these types of homes are in line from floor to floor. If the windows did not line up, there wouldn’t be any wall support. Balloon-frame homes usually have masonry or older type of stone foundations and occasionally concrete poured (photo 3).

(3) This house of balloon-frame construction presents the hazards of not only continuous runs from the basement to the attic but also of fire spread because of the subdivision of the structure from a single-family to a five-unit apartment building.

LIGHTWEIGHT CONSTRUCTION

What about lightweight construction? Although lightweight homes are still built the same as platform-frame construction (but with engineered materials), should another classification be established for them? Whenever it is known that lightweight construction is present, it should be reported immediately. This information may come during the initial radio size-up for all to hear or from the roof crew (truss roof) or the interior crew during overhaul (truss floor/ceiling) when the building is being exposed.

Identifying lightweight construction isn’t always that easy, but here are some clues that may help:

• The obvious source of this information would be your building preplans or walk-throughs. Nothing is better than seeing firsthand how something is built.
• Homes that just appeared in the middle of nowhere (“tract homes”) for which builders provided only a few floor plans and, in many cases, used lightweight construction. If any one of them has lightweight materials, assume they all have them.
• In a building with a large open floor plan (span 20 to 25 feet or more) unsupported, suspect some type of engineered (or lightweight) material to carry that span.
• Any homes or townhouses with intricate roofs and numerous gables or dormers are probably of truss construction. The roof is the most time-consuming component to build; therefore, many companies choose to use truss construction because the trusses arrive at the site preassembled. Homes with heavier roofing materials, such as slate or clay tile, are enough to give you pause that lightweight trusses probably are present.

During our radio size-up, do we report a 1½-story building as a two-story or a 2½-story as a three-story? Some would ask, “What’s the difference?” What about that half story? A story is defined as a level of a home that has full-height walls. The half story would indicate that the top floor is in the roof line and has windows. The windows may be on the gable ends or in dormers. The one-half story may be finished off to accommodate bedrooms. Access to this space may be difficult, depending on the size and pitch of the staircase in older-type homes. Some homes may have a second staircase leading to the second floor from the rear kitchen/entrance. When homes are 2½ stories or taller and have a first- to second-floor staircase run on an exterior wall, the stairs leading to the attic space (if present) are usually in a different location. A staircase positioned on an exterior wall doesn’t allow for enough headroom height to walk from the first floor all the way to the attic space. Therefore, you may find the stairs that lead to the attic in a rear bedroom/closet or closer to the center of the home adjacent to a hallway.

More importantly, though, the one-half story tells us of the presence of knee walls or collar ties that will act as ceiling joists, creating void spaces behind the knee walls and above the collar ties/ceiling joists. A fire in this void space that goes unchecked may take hold of the whole upper floor before you know it and does not become evident until fire is through the roof or the roof collapses.

The one-half story also tells the truck company opening the roof that they may need to extend their ventilation opening downward to open up above the knee walls. This is especially true if interior crews are having a hard time making the attic space because of high-heat conditions. It is important to recognize the presence of this void space, and companies need to be aggressive opening up the interior walls as well as in conducting vertical ventilation.

LIGHTWEIGHT WOOD FRAME

What if it is lightweight wood-frame construction? In older communities, most frame buildings are built with dimensional lumber and, therefore, can generally stand up better even under moderate fire conditions if attacked aggressively and properly. What if Engine 1 arrived and had the same fire conditions in a lightweight frame? Will its tactics change? The answer should be yes. Numerous firefighter deaths have occurred in the early stages of operation because lightweight construction was not identified and its early collapse potential was not considered. The point is this: Would you enter a fire building you know to be of lightweight construction as aggressively as you would one that has dimensional lumber? The simple fact is that dimensional lumber has a larger mass-to-surface ratio area than lightweight structural components and, therefore, holds up better under fire conditions. We have given up mass for shape.

While performing the initial size-up, take the time to understand the building and identify the type of construction. Another part of your initial size-up over the radio should be whether the building is occupied (lived in, not necessarily only if civilians are home or not), vacant (the building is structurally sound but currently no one lives in it), or abandoned (the building is obviously not lived in and has fallen into a state of disrepair). Knowing this information should dictate your strategy and the type of initial attack you will make, depending on the location and extent of fire. All of these buildings still need to be searched, but do not enter them aggressively; first consider construction type, current occupancy conditions (as defined above), and—most importantly—fire involvement.

ORDINARY CONSTRUCTION

Buildings of ordinary (masonry/Type III) construction are defined as those that have exterior masonry walls but may have interior structural components (walls, columns, roofs, floors, beams) that are of combustible materials (photo 4). These structures can be residential, commercial, or mixed occupancies. Many times, this type of construction is mistaken for a frame house that has a brick veneer (photo 5). Company officers size up these brick veneer homes incorrectly because they didn’t take the time to look at the entire building or they did not have sufficient training to understand how to identify ordinary construction. When we asked people to identify a house with brick veneer or—worse—a frame house, too many responded that it was ordinary construction. When asked what makes it ordinary, they state either because it has some brick or, in the case of the frame, because all of the houses are the same, “ordinary” construction. This reply highlights the lack of emphasis placed on the importance of recognizing building construction and how to accurately identify the five types.

(4) This former firehouse is of ordinary masonry construction. One of the dangers of commercial buildings of ordinary construction for the roof teams is the coping found along the parapet. Most of the time, this coping has come loose and is easy to knock off the wall. Personnel making the roof should never stand on the coping when coming off a ladder or tower basket. (Photo by Tom Tulipano.)

(5) This house has a brick veneer over the front (Division A) side. There is actually no structural benefit from this brick; it is purely for show. Additionally, this house is all lightweight frame. Under extreme fire conditions, the brick veneer could potentially suffer complete detachment and crush unsuspecting personnel who did not properly identify the construction features/hazards.

In many communities across America, most downtown districts and multiple dwellings are of ordinary construction and usually are no more than three to four stories in height. These buildings generally have a flat roof, thus creating a cockloft, which is the void space between the top of the interior ceiling rafter and the bottom of the roof joist. This space may be a few inches to several feet, depending on the roof pitch. Another feature that may not be readily identified with these buildings is limited access to basements as a result of coal chutes, bulkhead doors, and flush sidewalk doors. Basements may connect to adjoining buildings by under-sidewalk passageways (photo 6). Roof or floor collapse is generally the biggest hazard with these types of buildings; such a collapse may cause the exterior walls to collapse.

(6) This storage space is under a sidewalk in downtown Lockport, Illinois. At one time, this vault ran on each side of the street for three blocks. Although this one no longer connects to other buildings, others do, which presents a unique fire spread problem. It also allows firefighters to get water on a basement fire by breaching the sidewalk if they cannot make entry to the structure.

One of the greatest collapse hazards is the outward collapse of a masonry parapet. If the building is heavily involved in fire, establish collapse zones and maintain them throughout the incident. Collapse may not always occur, but it is likely. When a building suffers a significant fire, anticipate and plan for the collapse of the building to ensure the safety of the firefighters operating at the incident (photo 7).

(7) This building suffered collapse of the roof and the third floor during an extra-alarm fire in 2008. Although the walls remained intact, companies had been repositioned into proper collapse zones in anticipation of the walls collapsing.

RENOVATED BUILDINGS

Renovated buildings pose a significant safety threat to firefighters because significant changes made on the inside are not always apparent from the exterior, which looks the same. Sometimes, this work is obvious from the exterior (photo 8); sometimes, it is not (photos 9, 10). Knowing that alterations and renovations have occurred should cause you to pause and reevaluate your strategy and tactics when there is a fire in the building.

(8) This building is undergoing a massive remodeling. If this were in your response area, you would have no excuse for not knowing that the remodeling is taking place. Note such projects while out running fire alarms or EMS assist calls or on your weekly drill night. You would be killed if you were to attempt to fight fire in this building as if it were a building of “traditional” ordinary construction. (Photo by Hank Sajovic.)

(9) The new interior of the building in photo 7. Forty years from now, who will know this building is now lightweight construction? Looking at it from the outside, nobody would. Once it is finished off, nobody would. Take notes and photos, and pass them on.

(10) A single-story building of ordinary construction that had a second floor added. No effort was made to remove any of the former roof; it remains intact under the second floor. This is a type of void space that will kill and has killed firefighters.

Once the local fire department has become aware that a building has been significantly altered, there should be no excuse for members in that department not to be aware of the hazards created by the alteration or renovation. It is also the fire department’s responsibility to keep passing the information along to its newest members. Hopefully, these discoveries take place while the work is in progress during preplan/fire inspections and not when the building is on fire!

In many cases, the building’s exterior walls remain and some, if not all, of the interior structural components (roof/floor joists) were replaced with lightweight structural components (photo 11). The building in photo 8 will pose a significant hazard to firefighters if it ever burns again.

(11) Another view of the building shown in Photo 8. How is this building going to behave if it burns again? Again, get out there and document this! (Photo by Hank Sajovic.)

Imagine you are the roof team and cut a ventilation hole to find dimensional lumber for the joists and cut another hole and learn that you are standing on partially laminated I-beams or that the entire second floor is made up of lightweight wood trusses as in photo 11. Many times, these alterations are done without our knowledge, which is the reason it is imperative that your department or fire district be involved with the local building department so that these changes can be tracked, added to formal preplan documents, and passed onto future generations of the fire service. Too many firefighters have been injured or killed by code-compliant and illegal alterations. Keeping this information secret is a disservice to those firefighters. Pass it on!

Another easy-to-identify sign that an alteration has occurred is newer windows on an older building or window/door openings that have been bricked in. Although it doesn’t necessarily mean that major changes have taken place, it should keep you on guard that this building may have additional hazards as the result of alterations or renovations. Write down the specific hazards you see, or take photos when possible to document the changes. They can then be used in future training sessions and added to formal preplans. If you are on the property, make sure you have the owner’s permission, and let the owner know the purpose for the visit. As long as you don’t hinder day-to-day operations or work being done on the property, most owners will allow you to walk through with your fire company. Just make sure you politely explain what it is you are trying to accomplish.

The common theme here is identifying the hazards created by the type of building construction and alterations/renovations that have occurred in the building. Having a good knowledge of fire behavior and building construction methods and materials will dictate everything we do on the fireground. All of these buildings behave differently under fire conditions and should be dealt with accordingly. Arbitrarily saying we attack all fires the same (same size line, same leadout, same ventilation tactics) isn’t in our best interest.

There is enough information out there, backed up by solid engineering data, so that we should no longer be surprised by buildings that fail under fire conditions. It is up to all firefighters to study this information and put it to good use so that we don’t become a line-of-duty death statistic.

A building in most cases never collapses without some sort of warning. We say “most” because lightweight trusses have been known to just drop. If firefighters are unaware of construction materials, they may never get a warning. The warning signs of collapse may be present for years or for only a few seconds, but there are signs. We should not be surprised if a building that has been attacked by fire for a long time or has had thousands of gallons of water poured into it collapses. That’s why it’s important to size up your buildings properly and recognize what you are up against! As late building construction expert Francis L. Brannigan stated many times, “Know your enemy!”

MICHAEL J. LOPINA, a 22-year veteran of the fire service, is a lieutenant/paramedic with the Lockport Township (IL) Fire District. He is also an adjunct instructor with the College of DuPage Fire Science program. He is co-creator of the “‘Common Sense’ Building Construction for the Street-Smart Firefighter”curriculum.

TOM TULIPANO, a 23-year veteran of the fire service, is a firefighter/paramedic with the Lombard (IL) Fire Department. He has been a carpenter for the past 27 years and a carpentry/general contractor for the past 10. He is co-creator of the “‘Common Sense’ Building Construction for the Street-Smart Firefighter” curriculum.