On 10 June 1194 another fire caused extensive damage to Fulbert's cathedral. The true extent of the damage is unknown, though the fact that the lead Cameholding the west windows together survived the conflagration intact suggests contemporary accounts of the terrible devastation may have been exaggerated. Either way, the opportunity was taken to begin a complete rebuilding of the choir and nave in the latest style. The undamaged western towers and facade were incorporated into the new works, as was the earlier crypt, effectively limiting the designers of the new building to the same general plan as its predecessor. In fact the present building is only marginally longer than Fulbert's cathedral.Answers.com

One of the unusual features of Chartres cathedral is the speed with which it was built - a factor which helped contribute to its consistency of design as there appear to have been relatively few changes in plan as it proceeded. Australian architectural historian John James, who made a detailed study of the cathedral, has estimated that there were about 300 men working on the site at any one time, although it has to be acknowledged that our knowledge of working practices at this time is severely limited. The order of construction remains controversial. Normally medieval churches were built from east to west so that the choir could be completed first and put into use (with a temporary wall sealing off the west end) while the crossing and nave were completed. At Chartres however it appears that the building work started at the crossing and proceeded outwards from there, the eastern bays of the nave being the oldest and the ambulatory bays of the choir the newest parts.Answers.comIt had been argued that the original scheme was for an entirely new western facade but that plans were subsequently changed to incorporate the surviving west-work (which is why the westernmost bay of the nave is narrower than the rest) and the elements which had been prepared for its replacement were relocated to the south transept portal.Answers.com

It is important to remember that the builders were not working on a clean site but would have had to clear back the rubble and surviving parts of the old church as they built the new. Nevertheless, work progressed rapidly. The south porch with most of its sculpture was installed by 1210, and by 1215 the north porch had been completed and the western rose installed.Answers.comThe high vaults were erected in the 1220s, the canons moved into their new stalls in 1221, and the transept roses were erected over the subsequent two decades.

Each arm of the transept was originally meant to support two towers, two more were to flank the choir, and there was to have been a central lantern over the crossing - nine towers in all. Plans for a crossing tower were abandoned in 1221 and the crossing was vaulted over. Work on the remaining six towers continued at a slower pace for some decades, until it was decided to leave them without spires (as at Laon Cathedral and elsewhere). The cathedral was consecrated in 1260, in the presence of Louis_IX_of_France.Answers.com