Reading the Roof: Heavy Timber Truss Systems in Modern Commercial Spaces

Walk into many modern restaurants, breweries, and renovated commercial buildings today and you’ll see a familiar look, exposed wood beams, high ceilings, and a clean “rustic-industrial” aesthetic.

What you’re actually looking at isn’t just design. It’s a structural system that directly impacts fire behavior, collapse potential, and tactical decision-making. Understanding it matters.

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What You’re Looking At

The structure shown here is a heavy timber truss system with purlins. Unlike conventional residential construction where lightweight engineered trusses are spaced tightly together.

This system uses:

• Large, solid wood trusses spaced farther apart

• Horizontal members (purlins) spanning between them

• Roof panels or decking sitting on top of that system

This creates wide, open interior spaces with fewer vertical supports.

From the floor, you’ll see:

• Thick, dark wood beams forming the roof slope

• Cross members tying the structure together

• Smaller horizontal lines running across the ceiling (purlins)

• Flat roof panels above

How the Load Is Carried

Understanding the load path is key to understanding collapse risk:

1. Roof panels collect the load (snow, wind, fire weakening)

2. Load transfers to the purlins

3. Purlins transfer load to the main timber trusses

4. Trusses carry it to the exterior walls or columns

Failure at any point in this chain can compromise the entire system.

Why Firefighters Need to Pay Attention

At first glance, heavy timber can seem like the “good guy” compared to lightweight construction—and in some ways, it is.

The Advantages

• Large wood members char slowly, maintaining structural integrity longer

• Less prone to early, catastrophic collapse than lightweight truss systems

• Provides a more predictable burn profile

The Risks

• Connection points (metal brackets, bolts, plates) can fail early under heat

• Purlins create additional load transfer points—more pieces that can fail

• Roof systems often include insulated panels or void spaces, allowing hidden fire spread

• Open layouts mean collapse affects large areas at once

Tactical Considerations

When operating in buildings with this type of construction:

1. Look Up Early - Preplan

Identify:

• Truss spacing

• Presence of purlins

• Roof panel type

This tells you how the building is put together and how it may come apart.

2. Watch the Connections

Heavy timber rarely fails first—the connections do.

Be alert for:

• Sagging at joints

• Separating members

• Audible cracking beyond normal fire noise

3. Consider Fire Above the Ceiling

Even if fire appears contained:

• Insulated roof panels can trap and spread heat

• Fire can run laterally across the roof system before showing

Pulling ceiling early in the right location can change the outcome.

4. Respect the Collapse Footprint

These systems span wide areas.

If failure occurs:

• It won’t be localized like a single joist

• It can bring down large sections of roof at once

Establish and enforce collapse zones accordingly.

Not all trusses are created equal.

Heavy timber truss systems offer more time, but not unlimited time. They demand disciplined size-up, awareness of connection failure, and respect for the large spans they support.

The next time you step into a building with exposed beams and a clean architectural finish, remember one thing. It’s not just design, it’s your structural profile.

Until next time, work hard, stay safe & live inspired.

The After Action Review: Post-Incident Size-Up

The size-up is for all intents and purposes, our game plan or battle plan, if you will, against the structure we are working at. The size-up is where firefighters and fire officers gather information in order to make safe, efficient, and effective fire ground decisions. Fire ground decision making, as we know, is meant to be quick, but with an emphasis on safety and ensuring the tactics are done efficiently and effectively.

One aspect we do not stress enough is the fact we do not consider the culmination of the incident. After fire command is terminated and all units are back in quarters and in service. We must remember the pre-planning is not over just because we cleared the incident and everyone is back in the station and safe. This is where the add-value work is put into place and now it is time for the after-action review or post-incident size-up.

During the after-action review (AAR), firefighters and fire officers can discuss and share information obtained from the alarm and also discuss the success and failures they have experienced during the alarm. This is a time to ask a few question:

• What did we expect to happen?

• What actually occurred?

• What went well and why?

• What can we improve upon and how?

The benefit of asking these questions allow for strengths to be easily identifiable making it easier to uncover areas of weakness. By uncovering areas of weakness, you can develop ways to improve them! If you do not identify what went wrong, how could you ever expect to improve? On the contrary, if you do not understand what went right and why, duplicating that same success in the future will not be easy. Ensure necessary changes discussed in the AAR are implemented sooner than later as the longer it is on hold, the greater the likelihood of any changes being implemented diminish.

The size-up as a whole is a valuable step by step process for all firefighters, to obtain knowledge of their response district, riding assignments, and strategy and tactic implementation. By beginning this process formally or informally early on, it will allow for continual growth for each firefighter and fire officer. The key to success as an individual and team is to get ahead of the game and prevent ourselves from being reactive, rather proactive.

Until next time, work hard, stay safe & live inspired.

Exposure Protection: The In’s & Out’s

A well trained group of firefighters with a solid foundation of a good coordinated fire attack is critical to the success of fireground operations. Plan and simple. Understanding fire attack as well as fire behavior in particular structures also provides a good understanding of exposure protection. Many firefighters if not all firefighters heard of or know the acronym RECEO VS (Rescue, Exposure, Confine, Extinguish, Overhaul, Ventilate, Salvage) which is a critical thinking tool to assist with our tactical decision making based on the situation at hand. This article will talk about the "E" in RECEO VS - exposure. Something that is oftentimes overlooked. 

One third of our fireground responsibilities is property conservation. If we remember, L.I.P. (life safety, incident stabilization and property conservation). This stands true for interior or exterior exposures. Thorough size ups and a well performed search and location of fire will assist our needs of potential exposures and a way for firefighters to get ahead of the fire. One thing we always want to do, is get ahead of the fire before it gets ahead of us. 

A way to get ahead and hopefully stay ahead of the fire is to establish exposure lines in order to protect fire spread through the means of a secondary line(s). By doing so, we are allowing ourselves to stay ahead of any rapid fire progress and putting ourselves in a position to contain the fires forward progress. Fire can and will advance itself in any and all directions based through various ways.

1. Direct flame contact

2. Radiant heat

3. Convection

4. Embers

5. Heat contained in smoke. 

If we can understand where the fire is going, taking into consideration it's speed, type of structure and location to name a few, we can better position ourselves in front of the fire's flow path and cut off any potential exposure problem. 

Interior exposure considerations 

1. The BOX we are working on (4 walls, 1 ceiling, 1 floor). Heat travels up which makes the floor above the fire one of the most critical areas to protect. Don’t forget to check the floors below. Fire can drop floors just as easily as it can travel up floors.

2. Mushroom Effect. Top floors of a structure have a tendency to collect heat, smoke and products of combustion with nowhere to go. A calculated vent will help with reducing this effect.

3. Common cockloft. A hose line, a few pike poles and a TIC can help alleviate fire spread.

4. Interior design. Based on how the structure is designed can determine how fire will spread. Open floor plans present a great opportunity for fire spread since there is nothing to impede heat to travel and fire to spread. Open floor plans are common in both residential and commercial dwellings. Keep a look out for renovations as well. 

Exterior exposure considerations

1.   Structures on the sides of the fire building.

2.   Structures in front of the fire building

3.   Structures to the rear of the building

Note: exposure problems around the exterior of the fire building could be at risk of absorbing radiant heat, therefore hoselines on the exterior should direct their streams to the structures themselves to help reduce the amount of heat they are absorbing and not spray water in the opening between the structures. By spraying water between structures will still allow radiant heat to be absorbed by the exposed structures. 

A group of well trained firefighters in well trained hose deployment techniques allows us to get ahead of the fire before it gets ahead of us.

Until next time; work hard, stay safe & live inspired.

A New Decade

As we enter a new year, a new decade, we want to say thank you to all of our friends, followers and partners we’ve had throughout our journey and those we gained this year. Each and every one of you has helped us become better at what we do and helped us provide meaningful content to the fire service.

The next year will be a great year for us as well add more speaking engagements to our list and look forward to spreading our message to more people and more departments.

Without any of you, we couldn’t do what we do. When we started this, we didn’t expect the type of support and response we’ve received and we are wholeheartedly grateful for that.

From all of us here at The Firehouse Tribune, have a happy, healthy and safe New Year.

Until next time; work hard, stay safe & live inspired.

-FHTribune Staff

Why a RIC Team is Important in Today's Fire Service

Life safety on the fire ground is top priority not only for the citizens affected by the incident but also us as the first responders on the scene. By establishing that priority early on, it sets the tone for how firefighters can operate at that given scene. Each of us want to be safe and ensure we go home to our families and so do the ones overseeing the scene, they want and expect the same for us and themselves. Unforeseen circumstances could always arise in this line of work while working in an immediately dangerous to life and health (IDLH)atmosphere that could injury, trap or cause a firefighter(s) to go missing and because of this a dedicated team of specially trained firefighters or what we know as a rapid intervention crew (RIC), are to be established and maintained to rescue a fellow firefighter in distress. Going even further than that, this team must be incorporated into their incident management system and accountability system as per NFPA 2014. So what is the reason for this dedicated crew to standby incase a firefighter goes down?

Here’s are 5 tragic events that changed the course of the fire service and opened the eyes for the need for rapid invention implementation.

1. Columbus, Ohio on July 25, 1987. One firefighter fell through the floor into the burning basement, as conditions deteriorated and several rescue attempts using hoselines, ropes and ladders failed, rescue attempts were halted and this firefighter perished. The “Nance Drill” was then created from these events after it claimed the life of Acting Officer Firefighter John Nance.

2. The Hackensack Ford Fire in Hackensack, NJ on July 1, 1988. Five firefighters get lost and trapped while fighting a fire in the car dealership after the truss roof collapsed and ultimately claiming their lives.

3. Denver, CO on September 28, 1992. One firefighter became separated from his crew and due to a collapse, intense heat and heavy smoke this firefighter was trapped in a storage room with an aisle only 28 inches wide. Firefighters quickly setup ground ladders and removed window bars but it was ultimately too late. This firefighter perished on that day. The “Denver Drill” was then created from these events after it claimed the life of Firefighter Mark Langvardt. 

4. Passaic, NJ on May 9, 2001. One firefighter became trapped while searching for victims on the second floor of an apartment building.

5. Philadelphia, PA on August 20, 2004. Two firefighters were killed and a third was injured after becoming trapped in the basement of a one-alarm fire.

All 3 of these tragic events had no rapid intervention crew established. 

There are many reasons a rapid intervention crew could be activated on the fire ground and unfortunately this team of specially training firefighters are entering probably the most dangerous area of the structure; the place where a firefighter(s) is in distress and calls for help, otherwise known to the fire service as a “MAYDAY”. The reasons for a “mayday” vary but each one should be acted upon quickly and efficiently. 

Reasons for a “MAYDAY” and the activation of RIC.

1. Firefighters run out of air. Possibly due to large areas being worked in.

2. Excessive heat which could cause a heat stroke or a cardiac event.

3. Lack of visibility leading to crew separation and firefighter disorientation.

4. Crew separation due to the possible complexity of the floor plan.

5. Structural collapse 

At any given moment one of these could be messaged over the radio to the Incident Commander and the activation of the rapid intervention crew will need to take place. In order for RIC to be readily available to go to work, a few things need to take place in the anticipation something could go wrong at any moment. 

1. The first 10-15 minutes of a fire is most critical. Have RIC established early on and the RIC officer meet face to face with the IC for any pertinent information that could assist them in their efforts should they be activated. Establishing RIC from the start will help them with deployment and setup time. Also, most RIC established are outside agencies and will need time for travel.

2. The RIC officer should establish a staging area for the crew and all their necessary equipment along with devising a game plan should they be activated. 

3. Develop your own size up of the structure and make it continual throughout the duration of the job since things change. 

4. Determine how many crews are in the structure and the number of manpower on each crew. This will help with your S&T if you should be put to work. 

5. Assist with egress. Take a proactive approach and setup ground ladders for crews operating on upper floors. 

6. Time is critical. Stabilizing the situation quickly is the goal and working with the IC to develop a game plan for efficient firefighter removal (quickly yet systematically) before entering the structure will assist in those efforts. 

7. Bring the tools that are warranted for the situation. As mentioned earlier, RIC has a staging area for crew and tools so it is possible and necessary to stage more tools than you’ll need to go in with yet having excess tools readily available is just as important. 

Tools of RIC

1. Staging tarp for tools

2. RIC Pack – rescue SCBA

3. Forcible entry tools such as a Halligan bar or other pry tools

4. Stokes basket

5. 150-foot search rope

6. Wire cutters

7. Saws (i.e K-12, chainsaw)

8. Thermal imaging camera

9. Box lights

10. Strobe light to identify egress 

11. Life-saving rope/life belt

While there is no viable proof that having an established RIC in place will prevent firefighter fatalities on the fire ground, it is necessary in having one established and ready to go as a way to assist with the rescue and removal of a down fellow firefighter in hopes of a successful save. Any time departments are working on large structures, it is best to have rapid intervention crews on each side of the structure for quicker deployments with hopes of mitigating firefighter fatalities. Further, having an established RIC is a fire service best practice for all scenarios with firefighters working in an IDLH environment. May the lives of the firefighters mentioned in this article and the lives of all the firefighters who have gone before us in the line of duty, may they rest in peace. 

Until next time; work hard, stay safe & live inspired.

About the Author

NICHOLAS J. HIGGINS is a firefighter with 17 years in the fire service in Piscataway, NJ, a NJ State certified level 2 fire instructor, a State of New Jersey Advocate for the National Fallen Firefighter’s Foundation and is the founder/contributor of the Firehouse Tribune website. A martial arts practitioner and former collegiate athlete in baseball, Nick is also a National Exercise & Sports Trainer Association Battle Ropes Instructor, Functional Fitness Instructor and Nutrition Coach.  He holds a B.S. in Accounting from Kean University, and a A.A.S in Liberal Arts - Business from Middlesex County College. Nick has spoken at the 2017 & 2018 Firehouse Expo in Nashville, TN as well as at numerous fire departments within NJ and fire service podcasts.

Truck Company Operations: LOVERS__U

The fire service loves acronyms and we have a lot of them. For this discussion we are going to talk about the old acronym for all you truckies out there – LOVERS_U. Before we get into the acronym and details of it, let’s first talk simply about truck company ops.

Truck operations involve a variety of tasks; forcible entry, search, rescue, ventilation, ladder operations (ground/aerial), overhaul, etc. Nowadays with the lack of manpower, squad and engine companies may be needed to perform these operations at any time on the fire ground and are equipped with the tools to do so. Some engine companies may need to perform both truck and engine operations due to lack of manpower or the absence of a truck on scene and vice versa for companies who run quints.

Well here we are, a truck company; what do we do?

Let’s being here with LOVERS_U:

1. Size-up (Yes, truck has its own size up to do). Everything we do on the fire ground calls for a scene size up (and a continual one) to better help us make smart tactical decisions to effectively complete our tasks especially with ventilation. Can this start the LOVERS_U? Hmm….

2. Forcible Entry, if needed (for searching and fire suppression). Sometimes the doors may be unlocked so like they say, “trybefore you pry”. This action should be determined quickly upon arrival in the case of victim removals. Please remember to keep this simple. Remembering your basic tools such as the irons, a hook and/or saw along with variations or combinations of each, can save time and get the job done. The key here is to know your tools and how to use them efficiently.

3. Search (Rescue, if needed). This is very important because we are not only searching for victims but searching for fire both of which may or may not be identifiable from the outside which is why searching is critical on the fire ground. Let’s remember searching for fire can also be done by the suppression team as well. Don’t forget your TIC.

4. a. Ventilation for search team (Vent for life). By venting for life, it is allowing a lot of the thick, black smoke remove itself from the structure giving search teams inside better visibility and time for locating victims.

b. Ventilation for fire suppression (Vent for fire). By venting for fire, this assists the fire suppression team in making an easier push to the fire and much easier extinguishment. This is done with very precise communication between your crew, the suppression team inside and the IC. If done haphazardly, this can be catastrophic.

5. Ladder the building (ingress, egress, vertical/horizontal vent). Every window accessible should have a ladder on it for emergency egress and also for access to the roof and 2nd floor windows for vertical vent. Why not throw a ladder up while heading with your crew to your assignment? Kill 2 birds with 1 stone.

6. Overhaul/Salvage. Once the fire is determined to be out, now it’s time to get inside and open the place up. This is to look for any hotspots and perform another search should any victims have not been found. During this operation, SCBA is still required along with a TIC and hand tools. Using tarps are also considered to help salvage as much property as possible and avoid any smoke and/or water damage.

7. Utilities. This is also known as shutting  down the utilities. Depending on where the utilities are located, this is done by either an interior crew or an exterior crew. Having control of gas, electric and water will help increase the safety of all fire service personnel on the scene.

Now that we discussed primary responsibilities of the truck company, we can now collectively say we have described and discussed LOVERS_U. For all those on truck companies or working with truck company responsibilities keep this acronym in your toolbox when pulling up to a scene, during your pre plans and in your training. It’s a valuable guide to helping you get the job done efficiently, effectively and most importantly safely. 

Until next time; work hard, stay safe & live inspired.

 About the Author

 NICHOLAS J. HIGGINS is a firefighter with 16 years in the fire service in Piscataway, NJ as well as NJ State certified level 2 fire instructor and currently a State of New Jersey Advocate for the National Fallen Firefighter’s Foundation. A martial arts practitioner in Taekwondo, Brazilian Jiu Jitsu and Muay Thai as well as a former collegiate athlete in baseball, Nick is also a National Exercise & Sports Trainer Association Battle Ropes Instructor and studying for the Functional Fitness Instructor certification.  He holds a B.S. in Accounting from Kean University and is the founder/contributor of the Firehouse Tribune website.