vertical venting...

hey everyone. i am trying to put together some props to teach vertical ventilation at my department. we have gone over ventilation before, but it has always been horizontal venting. we have gone over vertical venting in the classroom setting but never really in a practical setting. i have an idea for props, basically building a simulated slanted roof with 2x4's and plywood. but i need advice from you guys on a few things...

1) how would you coordinate both vertical and horizontal ventilation operations to benefit each other and when would you do this?

2)in what conditions would you chose to vertically ventilate?

3)what are the pro's con's of vertically ventilating?

4)besides a chainsaw and pike, what other tools would you use for vertical vent operations?

5) once you have breached the roof (made a hole) what is the proper procedures for breaching the next layer or roof to get the smoke flowing through?

6) what are good ways to check that the roof you are walking on is solid and not ready to fall through? how do you check for this and what to you look/listen for?

like i said before, i personally have never been taught vertical ventilation, but i have been taught how to do horizontal ventilation. i dont think our department has even done vertical venting for real but maybe a handful of times and they were not really sure what to do.

thanks everyone, stay safe.

Okay I'll play along and answer by your numbers.

1) At most fires where vertical venting is done there is a combination of horizontal and vertical venting. Especially in SFD's. Most often the window or windows are used first with vertical venting to follow. Whether or not this is the best tactic is open for debate. IF roof venting can be accomplished quickly I think it would be more effective. Windows are easily taken and offer quick relief.

2) Where the fire was larger than a single compartment and rapid removal of heat and smoke were necessary for crews to more safely work interior. Obviously if there is any indication of backdraft potential vertical venting is a must.

3) Pros: Works great because it uses the natural convection currents to remove the heat, smoke and gasses.
Cons: More labor and tool intensive. More dangerous. Usually takes longer to accomplish. Truss roofs can't be trusted if the fire has extended into the attic space and a roof ladder is no guarantee of protection from falling into the attic space if the trusses give way.

4) Pick head axe to help remove roof boards. It is becoming popular in some areas to take a sledgehammer to the roof and simply beat a roof into the roof.

5) If the next layer is simply drywall or lathe and plaster use the handle end of a pike pole and reach down and punch the ceiling down. This will not work if the attic has a floor in it. In older homes with larger attic spaces you often see floors in attics used for storage. They may cover the entire attic space or simply run down the middle. Some are niled in place and some are simply laid on the ceiling joists. If you encounter this you can try pulling the flooring to see if it is naled down. Otherwise another way of venting may be needed.

6) If it is a truss roof and fire has entered the attic space the roof is suspect and most likely should not be walked on, even using a roof ladder. A safer choice would be to use an aerial laddewr ot tower and saty on them to vent.

Otherwise sounding the roof with the head of an axe may give you some indication. Looking for bubbling tar from the shingles, snow melting in spots, the roof steaming where water has been applied, smoke pouring through cracks. and listening for things like structural members giving way.

My answer was very basic and I am sure others will either add to it or crucify me for my answers. Good luck on your training. The IFSTA manual has some good info for you to use.

FyredUp

sounds like great info. 99% of our coverage area is single family homes, apartments, townhouses, or trailers. we do not have much if at all any commercial structures and we have 2 elementary schools. however our mutual aid areas have a large oil rig plant, a large industrial food plant, and some other commercial structures. our department does not have a ladder truck so everything we do is with ground ladders.

just needed the advice. whether or not we use it much, but its nice to know how to do these types of operations.

I'd throw in that vertical ventilation is way overused in many places. Generally speaking vertical vent should only take place when the fire is in the space below the roof (cockloft, attic, top floor). For peaked roofs we teach only when the fire is in the "A". It's sad how often we see first floor fires in 2.5 story or taller structures with a hole in the roof. Of course its pretty obvious after a vertical vent hole is complete if it was necessity. Fire and heavy smoke? Good job!! Light or no smoke? Check the ceiling was pushed down? Still no smoke? Bad call on the roof cut.

Other issues to teach: Vent for fire vs. vent for life.

As for tools, I like the K12 for 4 pitch or less, chainsaw above 4 pitch, flat head axe for manual skills or cut from the ridge, halligan (stays with the axe) for a foot hold and a roof hook for the pulling up the boards and pushing down the ceiling.

But, I would note there's some decent books and classes on vent, don't try and make up a class on your own. There's alot to it and leaving out a key peice could be very bad!

What is your definition of a "peaked roof?" Would that be a normal house in the south?

I've been up north and talked to some guys and they like freak out when you say you vent peaked roof's. My def of a peaked roof is like a normal house in the south... I would like others to define what it is

1) how would you coordinate both vertical and horizontal ventilation operations to benefit each other and when would you do this?

-Usually horizontal will be done before vertical. It doesnt take as long to do it. If it is just room and contents horizontal should be enough.

2)in what conditions would you chose to vertically ventilate?

-Also if you have balloon frame houses you will need to vertically vent if the fire is running the walls. If you have a heavy fire in the basement (smoke pushing out of the chimney) you will probably need to vent the roof. Doing this keeps the fire going up and out not all over the house


4)besides a chainsaw and pike, what other tools would you use for vertical vent operations?

-well i would use a vent saw not just a chainsaw on a roof. I will take a halligan or a pick-head axe. You can drive the axe into the roof and use it as a foot step for stability when making a cut.

Also when making your cuts you need to overlap your cuts. And i always make another cut down the middle of the four cuts this helps you knock the pieces in easier.

6) what are good ways to check that the roof you are walking on is solid and not ready to fall through? how do you check for this and what to you look/listen for?

If you have doubts about the itegrity of the roof you can use a roof ladder. As long as the ladder reaches the end of the wall and isn't a truss roof you will be safer on the roof ladder. You can also climb out onto the ridge and straddle the ridge. Then you are not on the roof deck at all. Then you would cut a hole not as deep but longer opening more bays. But the roof has to have a ridge board not truss for it to provide any safety. I like using the ridge pole when not on an aerial and it is a steep pitch. I like being on the ridge on a 12/12 pitch than on a roof ladder.

Quote:

---

1) how would you coordinate both vertical and horizontal ventilation operations to benefit each other and when would you do this?

---

I don’t think that there is any way you can coordinate the two. You need to handle each, in the order of importance for the fire you’re at. It takes time to get to the roof, and it also takes time to stretch into position.

Quote:

---

2)in what conditions would you chose to vertically ventilate?

---

Here, with the style of construction that is most prevalent, any kind of attic fire. However, we have a lot of homes that are balloon frame construction. I have seen it where the building presented a basement fire, only to have the attic fully involved as well.
Here is some video shot of a truck crew opening a roof here, taken last winter by a news helicopter.

http://www.youtube.com/watch?v=efHxjYmU_Y8

Quote:

---

4)besides a chainsaw and pike, what other tools would you use for vertical vent operations?

---

We don’t use chain saws on any roofs. We have always used circular saws. For years we used the Homelite XL-98, but have recently changed to the Husqueverna. All firefighters here carry an axe. If we're going up a peaked roof, two roof ladders always go up. If it's a flat roof, you may still need a roof ladder. It is impossible to have a set policy in place for every situation.

Quote:

---

5) once you have breached the roof (made a hole) what is the proper procedures for breaching the next layer or roof to get the smoke flowing through?

---

A pike pole works well, but I have also used a 14ft roof ladder to bust the ceiling down.
You do need to see what you get out of the hole first.

Quote:

---

6) what are good ways to check that the roof you are walking on is solid and not ready to fall through? how do you check for this and what to you look/listen for?

---

Know your construction, particularly in your first due. Find out if the majority of homes are built with actual wood members and nails. Older homes that have real structural members will with stand a lot of fire before they fail. The plates on newer trusses let loose very quickly. Roofs have a feel though, and if it feels weak, it is weak. Read the building‘s conditions; how much fire is directly under the roof, is it stem to stern, is the smoke pumping out from under the shingles.

Quote:

---

Originally Posted by JHR1985

What is your definition of a "peaked roof?" Would that be a normal house in the south?

I've been up north and talked to some guys and they like freak out when you say you vent peaked roof's. My def of a peaked roof is like a normal house in the south... I would like others to define what it is

---

If it isn't a flat roof ... it's peaked.


Why would the guys "up north" freak? Here in the northeast, venting a peaked roof is a standard operational procedure.

Some very good answers to your questions have been posted so I can only add these. 1. Always wear full PPE and SCBA. 2- IF possible keep your back to the wind so when the nasty stuff comes out it will blow away from the FF's. 3- Have an assigned radio for the crew on the roof. 4- Once the assignment is complete get off the roof. I added this because if the fire area is boiling with hot smokie gases (extreme heat), and once your crew opens it and the fire boils out it will not take long to make that roof even weaker.

Another good tool if you are in a rural area is to see if you can aquire (sp) a house that is going to be torn down, then see if you can use it for Forceable entry, ventlation practice, etc...

Stay Safe, and train, train, and train.:D

T.J.