Ventilating a fire by making a hole in the roof is a normal firefighting strategy, but it can be done faster and safer than having a firefighter get on the roof with an axe. A simple circuit of explosives can be used to make a fast hole in the roof, buying minutes of lower temperatures for firefighters. It can be thrown on top of the roof and remotely detonated.
It can also double as a way to make a quick entrance/exit for rescue attempts, although this has already become a tool in other industries/services.-- twitch, Jan 13 2009 E-Z Breach http://www.ezbreach.com/Never worry about locking yourself out of the house again! [MikeD, Jan 14 2009] This is a great idea. I, however, would not want to be the fire-man tasked with running up to a house fire with a high-explosive hoola-hoop. [+]-- MikeD, Jan 13 2009 C-4 should be alright. Best to wait for 8th to chime in on that one though.-- 2 fries shy of a happy meal, Jan 13 2009 Haven't seen him around lately. I'll attempt to draw him out.
"Cats".
Now we wait.-- Texticle, Jan 14 2009 It seems to me that to cut a hole a small explosive charge would have to be embedded in the roof - otherwise the blast would all go up and out.-- bungston, Jan 14 2009 blast would not have to go up. simple demolition explosive/anti-tank techniques could be employed, directing all energy downwards.-- twitch, Jan 14 2009 "Ooops, I didn't know you were standing there sir! I bet you looked very handsome before you got hit by the debris of the explosion..."-- PauloSargaco, Jan 14 2009 Explosives such as C-4/P-4 are usually used as cutting charges. A few wraps of det-cord around a hulla-hoop would do the trick if not for the truss supports. Linear shaped-charges are no new hat. I suppose a toroid shaped-charge would do the trick without too much shrapnel.
But, in my professional opinion, I beleive a water-impulse charge would be best suited for this.
<link>-- MikeD, Jan 14 2009 There's a chainsaw made especially for cutting into roofs. The bar is at a 45 degree angle to make it easy to use on the sloping roof.-- nomocrow, Jan 15 2009 //Now we wait.//
I heard a wailing noise outside that sounded something like "EOSSACR!", but I can't see any sign of its owner.-- pertinax, Jan 16 2009 [MikeD] det cord won't do it, unless it's a house or something (and tamped). Your link looks neat though.
I would *not* suggest using C4 as the breaching element: it's way too fast, you'd break all the trusses. Likewise an earthmover like Tovex is too slow, you'd blow the roof into the basement before you put a hole in it... you want the baby bear's "just right": something that cuts a hole in the ashphalt without breaking the beams... maybe an echo "radar" thingie to find out where the supports are then blow around them.-- FlyingToaster, Jan 17 2009 random, halfbakery