Upgrade the standard sliding door to a single door or double door (pictured) with hinges, low threshold entry, and locks for security.
Door comes with it is own outer frame which sits low to the ground and provides a "low-threshold" opening - customer has to cut section out of Foundation Frame.                                                                    
 
*Important Note: can not ship by UPS/FEDEX - has to go freight - usually at least $400 - but no extra freight to ship with a greenhouse!!