Simply measure from the outside edge of the architrave on one side to where the doors meet in the centre and from there to the outside edge of the architrave on the other side. Enter these measurements into the website. For the drop measurement simply measure from the top of the architrave to the floor and select “Outside Mount”. These blinds need to be ordered as separate blinds. Just Roller Blinds are able to make blinds up to 3000mm wide but you are limited to which fabrics you are able to use on big blinds. Simply enter the size of the blind in the ordering/pricing section of the website. The next step is to choose a fabric and colour. The website will only list the fabrics and colours which are able to be made in the size that you have requested.