1) A room in a house set aside for a particular person’s use.
1524 Richard to have iij [low]er chambres and iij over chambers at his pleasoure, South Crosland
1561 Edmound Robertes haithe had a chamber in Hull whereunto he commith and goithe
1587 I will that my brother ... shall have chamber rowme for his loudginge wher he now lyethe, Potterton.
2) In some contexts this was apparently a reference to a piece of wood but the exact meaning remains uncertain.
1634-5 all the chambers and jeists in the house wherein I dwell, all fotherams, bowses, balkes and hekes in the laithes, all timber logges about the house, Clint
1640-1 I give to my sonne Henrie all my boordes, chambers, baulktrees, louse timber and husbandrie geare, Thornthwaite. Perhaps it referred to items suitable for use in the timber-work of an upper room. Used as a verb, two examples have been noted: 1619 stye chambringe, Brandsby
1761 3 Men a day Chambring the pitt 3s, Tong. Perhaps the first of these referred to constructing an upper floor and the second to the enlargement of an open space.