Replies to This Discussion

Permalink Reply by Marques Bush on October 25, 2008 at 1:54pm

Well I guess I will throw myself out there. I definetly looking at the size of the fire when I arrive. Is it advanced or are we still in the growth stage. Also looking to see if it is peaked or flat. Is it old or new construction. If it is a commercial building I should be looking at the pre-plan enroute to the call. I like to ride my district and watch the new construction being built and if it was some of the new residential homes being built, it would really depend on the type of fire conditions. If I arrive and smoke is coming from the eves and soffit vents I'm going to assume I already have fire in the cockloft and I know if I wanted to vent vertically I only have a few minutes if it hasn't self vented. It is once in a blue moon when we use vertical ventilation so hopefully the more experienced folks will chime in. Great post!

Permalink Reply by Jay Lowry on October 25, 2008 at 6:20pm

The critical factors to consider:

1. Time - How long has the fire been burning. In the example you are talking about engineered roof systems. When was the fire discovered and when did we arrive on scene.

2. Where is the fire - If the fire is above a drop ceiling no one steps on the roof. Vertical ventilation will be performed by the fire.

3. Time Gauge - This can be tricky because no two buildings are alike. If in the first ten minutes (generally) headways has not been made it's time to go defensive. Here in Charleston one of the primary lesson, out of many, is risk analysis. Is it worth it? Venting from a stable platform - such as the platform above is one thing - putting people on a roof that is designed to fail isn't the best idea.

Permalink Reply by Marques Bush on October 29, 2008 at 8:16am

Risk analysis is something I definitely could use great suggestion.

Permalink Reply by TrainingTECH1 on November 6, 2008 at 8:24am

Good tips.

It is very important, obviously to know where the fire is, but also to have an idea of where it is going.

If we are doing a peaked roof, I like to lift up the shingles on the roof edge to get an idea of what is underneath and how thick the covering may be. Most building codes allow for a maximum of two layers of shingles, but I have seen three and four. If you can get a look at the decking, it will gove you an indication of the thickness of that as well. We did a job one day and the roof was covered in paneling!

Finally, for commercial buildings you just need to know your area...and have some common sense. You are never going to cut the roof on a newer highrise! It is the lightweight construction type buildings I would focus on. We use a chainsaw on residential roofs, and a Rotary saw for commerical..period. Cutting a residential roof with a rotary saw can be difficult as the saw will bind in the wood.

Finally whenever I am on a roof I look at natural ventilation features. Many older houses and commerical buildings have ventilators of some sort. If they can be removed easily take on off in the vent area to size-up the roof. You then also have a automatic purchase point. Any ventilator that spins (they spin due to the heated air, and in turn draw the fire to them) I will remove unless I want the fire to go that way. You may end up with a lot of little holes in the roof, but stand a better chance of containg the fire.