What is the bifolding door? The standard outdoor patio door or conservatory door has always been a solitary pane system, or conversely a French door. The bifolding door takes this one action additionally by providing a completely retractable system which can be made up to 10 metres broad. With http://clasps59360.thezenweb.com/Bifolding-Doors-What-Are-the-Perks--19155065