Short answers, pulled from the story.
Philibert de l'Orme arrived in the world between the 3rd and the 9th of June 1514 within the bustling city of Lyon. His father Jehan de L'Orme operated as a master mason who employed three hundred workers during the 1530s to construct prestigious buildings for the local elite.
In 1555 he demonstrated a new system called charpente à petits bois before the King. This technique used much less wood than previous methods while remaining quicker and less expensive. He applied this method at the new royal Château de Montceaux and at the hunting lodge in the Forest of Saint-Germain-en-Laye.
The death of Henry II of France occurred on the 10th of July 1559 leaving de l'Orme without a patron. Two days later on July 12th he was dismissed from his official posts. An Italian artist named Francesco Primaticcio replaced him with work that was then very fashionable.
Major commissions included the Château de St Maur-des-Fossés and the Château d'Anet built for Diane de Poitiers. He also worked on the Château de Chenonceau in the Loire Valley and the royal Château de Madrid located in the Bois de Boulogne. For eleven years he supervised all royal architectural projects except changes to the Louvre which were handled by Pierre Lescot.
De l'Orme died in Paris in 1570 while this major project remained underway. During the reign of Louis XIV de l'Orme's reputation suffered significantly as styles shifted away from his work. The grand stairway he built at the Tuileries Palace was demolished in 1664 to make room for classical structures.