Bike shed solutions/ideas?

[fazersharp]

[size=1em]The problem I see with trimming the bottom of the door is that it weakens the security of the doors, because then they will just be closing against the jamb, which is merely screwed into place. And if some of the jamb does need to be removed, worse still. Also, there is a securing bolt mounted at the bottom of the door which locks by sitting behind the jamb. [/size][size=1em]Still thinking...[/size] :\

I dont think you need to worry too much about security as for a start they are thin wooden doors and that little bolt (held in place with 10mm screws ?? ) one little tug and it will just fall off.
Better -20mm ply covered with a sheet of galvanised steel with any attachments being bolted all the way through with a rounded head on the outside.
Or get yourself on ebay and buy cheaply a set of upvc patio doors, there are always some on there when people take them out for an extension.