http://www.vententersearch.com/ This is from a website which is set up and used by firefighting professionals, largely devoted to gaining entry to homes and buildings. I stumbled upon it while researching ideas for up-armoring doors. It contains a wealth of information from the perspective of one who is trying to make his home more secure and, conversely, from the perspective of one who is trying to gain entry to another person's home. I shook my head while reading some of the articles, thinking "this would be a goldmine of information for a burglar." Anyway, take a look, it may give you some ideas that you haven't considered. Below is a typical article. Interior Security Bars June 07th, 2012 | Category: Outside Functions Captain Rick Cravero from Tamarac (FL) sent in these photos of security bars on the inside of windows from a local neighborhood. When the windows are shut, the bars appear to look more like french window panes instead of security bars. One thing that may give it away is that in this particular case, is that not many jalousie windows had french panes. These particular bars are simply held in place by some self-tapping screws into the original window frame. These bars may slow us down a little, but shouldn’t be much of a match to a determined firefighter. Depending on how the window frame is secured (how many screws were used), pulling on the bars may remove the entire window frame. If the window frame is well secured, then inserting either the fork or the adz of the halligan in between the window frame and the security bar assembly to separate the bars from the window frame would speed up the removal. Once the frame of the bar assembly is weakened and separated from the frame in a few places, the entire bar assembly should be able to be “hinged” away from the window opening. The rotary saw always remains an option, but believe it or not, the hand tools may end up being quicker. The main thing to consider when faced with bars is to remove them early! Waiting until conditions deteriorate, or worse, when a fellow firefighter needs to bail out is not what we should be doing. Trying to minimize damage to the structure by waiting to remove them may actually cause more damage in the end. Simply open it up, and get the job done!