hello, i have a question about mortice latch/locks and if there is any difference in their design dimensions, when it comes to commercial and residential. **the specific question is asked at the very bottom, after the descriptive passage my mother has been updating her home over the past couple years in preparation to put it on the market , when i mention home, its a house that sits on, a somewhat small amount of acreage (40 or so acres, it might be more no less than 40 though) anyways along with the house there are 4 other structures 2 which are hay barns, one is what ill call a lean-to, and the 4th which is a 40x50x16 ibeam frame steeel building ( a shop) that is from her account stated to be ar least 40 years young The west side of the building has 2 regular sized steel frame steel door with security glass in both ( security glass beign the the i guesss now "old" wire mesh within the glass pane moutned in the door. it looks like square diamonds or very close nit chicken wire within the glass The sw corner entry door is the one that my mother asked if i could get it functional. the door aat the sw corner had to be removed and replaced ( i forget why i beleive a due to a storm and debris from sustained winds impacting the security glass pane and breaking it. mom went and from guessing in trying to save a few dollars (if it was effective idea or futile effort is another topic) soooo instead of sourcing a new or used identical door with the glass intact there is this steel door with only the hinge mounts and the lever/knob hole precut The hole and or cavity fr the latch lock mortice needed to be cut out, she called it a Door Blank? which i have no idea as to the accuracy of that term and then also if the usage of it is also acurate it makes sense in a fundamental definition etc steel being less forgiving than say wood and since its a entry point. and i wanted to get the proper end result of the door functioning as it should. i have been tryign to educate myself on cmmercial residential door installation topics etc i bought a latch lock hole cutting jig, to install the knob/lever that mom had bought. and which brings me to my question in regards to thinking that there is a defintive difference in the latching locking mechanism of a commercial one vs a residental one. she gave me a residential keyed entry door knob to install and it doesnt seem "fit the bill" the locking motice candidly speaking or word play seems to fall shortof achieving the goal (the locking latching mortice of the residential doorknob assembly, doesnt seat into the latch reciver in the steel commercial doorframe,, or far enough in to secure it. (a guessitmate, would be it needs to be 1/2 inch or so longer than what it is is the latching locking mortice in a commercial leverknob assembly longer than that of a residential locking latching mortice ? and is the trim or bezel plate that mounts to the door frame specific or matched/mated to the brand or mfg of the door lever/ door knob etc will i need to have her purchase a designated Commercial deemed keyed entry door lever/knob assembly ive been of the opinion that the residential commercial designation is there for a reason both in generically or as a broad descriptive term and then also notates specific design details specific to each catagory if the residential knob/lever assembly "CAN" be made to work properly without too much efforrt beyond that of a medium skilled experienced diy handyperson if hyper links could be provided as to how to do that would suffice to be respectfull and appreciateive to yall. so ya dont have to spend bunches of time typing it out anyways thank you for your time and effort in regards to this and i look forward to corespondence on this Holly-Jo Thompson