Truss roof protocols?

[WD6956]

Just wondering what your department SOP is for known exposed truss roof commercial buildings. Examples are Home Depot, Lowes, Some restaraunt's, etc. We have the policy that we will not on the roof if their is fire below. But what are yours and what are your search procedures?

[Truck_3]

My personal policy is not to be under one which is involved in fire. Throw a metal deck roof into the mix and it's gonna take you too long to really get a good vent going unless you have ready made holes, ie Scuttles, Ventilators, Skylights. Punch what you can and get off. If you have a heavy roof load with HVAC and other BS along with lightweight Construction, don't do it. The Effin' building is not your friend.

[LaFireEducator]

Volunteer department we have identified most of the buildings in the district with truss roofs, and have basically implemented a no entry policy, which includes no roof work, if in the judgment of the first arriving officer, the fire has entered the overhead space or truss space.

Combo department, which I work full-time for, has a less rigid policy regarding operations in truss buildings, but it seems like we headed the direction of a firmer no-entry and no roof work policy. Right now we are operating in this direction with fires that occur while the building is closed, as the fire has more than likely gotten a pretty good head start as few commercial buildings in our district have alarms, and the first report of fire in a closed commercial building would be an exterior report of smoke or fire.

There is simply no reason to attempt to attack a fire, which includes being on the roof, in a truss building, unless it is very contained and not into the overhead void space, given it's rapid collapse history.

[Rescue101]

That's why we bought a PLATFORM. T.C.

[slackjawedyokel]

Why does everyone paint truss roofs with such a broad brush ?

[mikeyboy411]

Truss Roof Policy

Our policy is we vent them as needed..... Yes, even commercials..... Just because it's a lightweight truss doesn't mean you shouldn't get on it, IMHO. Let the situation dictate if it's a Go/No Go situation.

As far as venting the attic, I say do it. We've had good success with venting attic fires. We work away from the fire on strong wood. A good rule of thumb that I use with my Truck Company is: conventional construction heat hole goes over the fire, lightweight construction heat hole goes close to the fire on/in good wood. If you're talking flat-commercial lightweight construction, I say still vent it but work off your main structural members (think beam(s) here). An effective vent hole does not have to be perfectly square so cut on the fire's side and drag your head-cut parallel to the main structural member. If you have (2) saws working (which you should on ALL commercial vent jobs) have the 2nd saw cut the #2 and parallel cut. Keep the sections attached to a rafter and dice the size needed. Once the head cut is made, the original sawyer can prep the #4 cut. Louver the pieces, check the heat hole is efficient in size and get down. Obviously there are a couple more steps here, but this seems basic to me.....

Just because it's lightweight construction doesn't mean I'm gonna take my tools and go home or just let it burn. Seems easier to modify my travel route, train, train, train, make the heat hole, confirm it's working, and then get off the roof.

For the FDs out there that don't operate on lightweight trusses I'm curious do you confirm it's lightweight, evac out, set-up exposure protection 1 1/2 times the height of the bldg and let it burn? If we did that, we'd let approx. 80% or so of our bldgs burn down so it makes me curious the thought process associated with this mind thought.....

[LaFireEducator]

Just because it's lightweight construction doesn't mean I'm gonna take my tools and go home or just let it burn. Seems easier to modify my travel route, train, train, train, make the heat hole, confirm it's working, and then get off the roof.

For the FDs out there that don't operate on lightweight trusses I'm curious do you confirm it's lightweight, evac out, set-up exposure protection 1 1/2 times the height of the bldg and let it burn? If we did that, we'd let approx. 80% or so of our bldgs burn down so it makes me curious the thought process associated with this mind thought.....

Some perspective on this.

My combo department may run to a working commercial fire once every 5 years. It's probably more like every 7 or 8.

Majority of those are older structures which are either beam or perlin covered by a metal skin, not truss.

Volunteer department it's probably once every 10 years we run to a commercial fire.

The point is that these fires are very rare events. The simple fact is we have very little experience operating in commercial structures as the events do not occur to build up any type of experience level.

We are not burning up the town. We are just protecting the guys.

[mikeyboy411]

Ahhhhhh, ok... Thanks for clarifying that...... I've got some good training for ya to demonstrate what I was telling you about, if you're interested send me an I.M. with an email and I'll share it with ya.

Build a Commercial Prop at your FDs Training Center and practice there so that you feel more comfortable operating on them. Cool thing is that you can build it to the specs of some of your problem buildings and come-up with techniques that will work for you in a controlled setting.

[mikeyboy411]

Majority of those are older structures which are either beam or perlin covered by a metal skin, not truss.

If you have beams and perlins then you're talking conventional construction (panelized or whatever). Traverse your beams as much as possible, traverse onto the perlin (sounding obviously), get over the fire and cut your Heat Hole while working off the perlin. Make your cuts skinnier and run them parallel to the perlin your working on.

Most carbide tips will cut metal roofs up to 7 cm (or is it mm) thick, so it's possible to cut with a chainsaw. You might want to think about upgrading to a Raptor Chain or Bullet Chain for your commercial vent jobs. Another option is to cut the decking with a Rotary Saw or (2) but I don't know if this is an option for you. I was going to get more detailed with this but I'm gonna stop here.

[dfwfirefighter]

Why does everyone paint truss roofs with such a broad brush ?

I'm agree. Knowing what type of truss a building uses is the key to safe and effective fire suppression with regards to that feature in a building's design.

Some trusses hold up fairly well during a fire. Most do not. I guess that why Vince Dunn says "Don't trust the truss".

[rescuedawg]

Around here its easier to mark the ones that arent truss construction. Every 7,000 sq.ft. plus summer McMansion is engineered truss construction along with all new commercial. Then there are the historical preserved buildings, they are all baloon construction.We cant win.