To contain my escape artists I took wooden pressure mounted babygates and added thin/cheap plywood from home depot that I had then cut to the inside measurements of the panels of the gates. I popped those in on the side that faces the ferret room and secured with a little wood glue from the other side. When the tallest of the escape artists realised that he could jump and hang from it and sometimes pull himself over I added something further. I bought corrugated plastic (because it is lite but still durable) and cut it to the size of the door frame I was putting the gate in, wrapped the sharpish edges in duct tape and used adhesive velcro (thicc) to attach it to the top of the gate/bottom of the extension. On the gate it will be two seperate but long sections so that the gate can close. If this dosent seem secure enough you can add velcrow tabs to the door frame/top sides of the extension or add command hooks to the door frame and add a bit of elastic (or a hair tie) to the top corners of the extention. – corinne