An increasing number of single-family houses are being built in clusters in many areas of the country. Houses are placed close together in the development to promote interaction between the residents and provide common open spaces. Often two and three stories tall, these clustered houses present challenges to firefighting that require some adaptation from a traditional residential response. I was inspired to write on this topic after reading a conversation on the Web forum Prevention Advocacy Resources and Data Exchange (EPARADE) between two of my friends and respected colleagues, Ozzie Mirkhah, fire protection engineer for Las Vegas Fire and Rescue, and Michael Love, fire marshal for Montgomery County (Md.) Fire and Rescue.
Cluster houses built today employ modern construction techniques, including lightweight wood trusses, vinyl siding and other construction features that ensure a hot fire. In many cases, houses are situated no more than 10 feet apart with, at best, 35-40 feet of street frontage. Walls are generally not fire-rated. There will be gypsum board on the inside of the exterior wall, but combustible material on the outside of the wall will facilitate spread from the fire building. Windows are likely to be present on the facing walls, and, due to the commonality of designs, there’s a very good chance the windows will face each other, which can further exacerbate the potential for fire spread from dwelling to dwelling. Further, narrow streets and limited off-street parking may create severe access challenges to firefighters, especially during holidays and weekends. Cluster developments often feature dead-end streets that limit apparatus access once a supply line is laid.
Apparatus Placement
Since the street frontage for these houses is limited and there’s clearly no access for apparatus on Sides B or D (and perhaps only limited access on Side C), placement of apparatus becomes critical. In order to minimize the collapse risk presented by lightweight construction, ensure firefighters have aerial ladder access on Side A (and perhaps Side C) to work the roof with the aerial stream. Tip: Using the aerial to access third-story windows or the roof of a two- to three-story cluster house is much safer and more efficient than ground ladders. However, if two engines arrive simultaneously and take positions in the front of the building, it may become difficult for the aerial to get a usable position anywhere near the dwelling.
There are other apparatus placement challenges presented by cluster houses. Many feature rear-entry garages with limited access driveways/alleyways in the rear of the dwellings. There are a number of things that can block access through these driveways/alleyways, including parked vehicles, delivery vehicles, snow or ice.
Fire in a rear-entry garage may be best attacked with a line entering Side A. There may not even be obvious signs of fire from a rear-entry garage to apparatus arriving in the front of the home. On the other hand, apparatus arriving on Side C may be able to easily stretch a line, but firefighters must be careful not to push the fire into the dwelling or “cross streams” with a hoseline crew that has entered from the front. Apparatus arriving first on Side C may experience great difficulty making the stretch should they decide it is more appropriate to take their handline around to the front to make their attack. It might not be easy to stretch a line between houses, and the crew must use a long enough line to make the stretch.
Attacking the Fire
Gaining access to the building for rescue and ventilation will be a key objective. Firefighters may ladder the front and rear of the dwelling but might also need to ladder the side windows to perform rescues. There are a lot of challenges in raising ground ladders to the sides of these houses due to the proximity of neighboring structures, which have only a few feet to the property line. These challenges can slow rescue efforts and roof ventilation, allowing for greater fire spread and reducing the time that firefighters have in the building and on the roof.
Firefighters also face greater risk operating in and on the building. Many fire officers may be hesitant to send firefighters onto the roofs because of their lightweight construction. Tip: Some houses are constructed with an attic ventilation fan. If it’s safe to access that area of the roof, removing the fan hood/shroud can quickly ventilate the attic. Removing gable vents is another ventilation technique crews may employ with limited manpower. Of course, ladder access will be necessary to make this happen.
There are many similarities between cluster houses and the infamous “three-deckers” found in New England. These three-story wood-frame houses with wooden porches on all three levels are often constructed close together and present rapid fire-spread challenges. Aggressive attack strategies are needed in three-deckers, including throwing numerous ground ladders, for which the Boston Fire Department is famous.
The major difference between three-deckers and cluster houses: their construction materials. The lightweight construction of cluster houses presents faster collapse potential than the balloon-frame construction of three-deckers, which firefighters must keep in mind.
It’s also worth keeping in mind that gas and electric meters may be located on the sides of the dwellings between houses. If the gas meter on the adjoining dwelling becomes involved in fire, it might not be controllable until the utility company arrives and cuts the gas at the street. Until that happens, fire here will quickly spread fire to the exposure home.
Laddering the Building
Laddering cluster houses presents challenges to firefighters. With 10 feet or less clearance between homes, the ability to raise a ladder with the proper climbing angle to a second-story windowsill for rescue/entry purposes can be quite difficult. A flat raise will be impossible-ladders in this space must be raised with a beam raise, a tactic that requires practice to complete. Two or three very capable firefighters will be necessary to place a ground ladder able to reach the second floor or roof-probably a 28- or 35-footer-and then perform a beam raise. Many departments simply lack the manpower to ladder these buildings safely, and many may not carry ground ladders longer than 24 feet. Very few engine companies and, unfortunately, fewer ladder companies than ever carry ground ladders longer than 35 feet.
Raising a ground ladder at a cluster house becomes even more difficult if the lot slopes downward from the front to the back or if obstructions such as bushes or fences are present. Both of these are relatively common design features in cluster homes, as they facilitate a walkout basement in the rear of the home. If a walkout basement is present in a three-story home, firefighters in the rear will essentially be looking at four stories, making it very difficult to reach upper-floor windows for rescue with ground ladders. Even two-story houses with a walkout basement in the rear will require raising 35′ ground ladders in Division C to make rescues. Note: Fortunately, model codes require “rescue windows,” larger-than-normal windows designed to give firefighters more space for ingress and rescue, in new residential construction.
On the Inside
The open floor plans of many of these houses will allow for fire, heat and smoke to quickly spread throughout the building. It will also allow for hoselines to be more easily stretched to many various locations. The heat, smoke and water spread will also increase the need for salvage, and these factors are likely to require additional manpower to achieve fire/rescue objectives at these homes. Extra manpower may also be needed to check for fire spread into exposure buildings. Note: Although the fire alarm may be active in the fire dwelling, it will not transmit to adjoining buildings until fire enters those dwellings. Consequently, there may be a delay in alerting neighbors of the need to evacuate.
Further Considerations
Cluster developments are often built outside of downtown areas. Many larger departments may concentrate their ladder companies in downtown areas and only staff engine/ambulance units in the outlying areas, which can result in delayed response for aerial apparatus. When many of these outlying stations were constructed, multi-story houses may not have existed, and the stations may not be capable of housing aerial equipment without making structural modifications.
City planners must be aware of the amount of work necessary to fight fires in these developments and must consider a variety of tools to reduce fire risk. Above all, residential sprinklers should be a primary tool in their protection. Sprinkler systems make firefighters’ jobs easier and safer in these densely built, lightweight structures.
City planners must also ensure all fire stations can accommodate ladder companies or quints, even if your department isn’t planning to add one at the moment. Note: ISO? wants to see ladder company distribution within 2 « miles of each area of response. While this certainly isn’t possible everywhere, departments must take this under consideration during their master planning efforts. Planners must also consider adequate apparatus turning radius in these developments. The International Fire Code? has some specific turning radius requirements-but they’re in the appendix and thus not a requirement unless your jurisdiction has specifically adopted that appendix.
Conclusion
Although city planning and fire station design are beyond the control of the line firefighter, planning tactics for fires in cluster houses is not. One of the best training exercises departments can use to prepare for these fires is obtaining permission to work on one of the houses during construction, when it’s framed out but finishes have not yet been applied. Practice stretching hoselines into the various rooms and raising ladders to various access points to ensure you’re ready when you get the call.
