Though books have a prominent role in Chaucer's fiction, the library does not. Chaucer coins the word "library" in his translation of The Consolation of Philosophy--known as the Boece--and uses that word just twice throughout his fictional corpus. He uses the word "study" as a synonym but employs that word just twice also, both times in The Canterbury Tales. As Chaucer is perceived as a great commentator on the pains and salvations of reading, and since libraries are a fountainhead for medieval reading, there is an interesting discord in his benchmarking literacy while invalidating the reading center. That Chaucer should be almost incognizant of the preservers of textual knowledge shows the library as a virtual nonentity for English readers of the 14th century. It is as though the library is an empty estate, a medieval orphan to a new birthright of reading reestablished by Chaucer by a melding of thought between traditions of classical and Christian reading.
It is obvious to the 21st century that the reading space should accommodate texts if readers have a stake in suitable collections. Chaucer wrote when the library was a vested fulcrum to language and education. Although public libraries did not make their appearance until the early 1400s, as the literacy of the growing merchant class increased, there was an attachment between public life and private reading. . Church and legal administrators required the study of history and theology, and Cambridge and Oxford universities flourished as collections increased for their scholars.  In the 14th and 15th centuries, the new "secular mind" became appreciative of classics after a long decline of Greek and Latin study.  A vigorous collection of manuscripts revived classical learning while preparing discussions on religious, moral, educational, and political issues. The personal library began to appear in this time, although lay and church writers had small collections of books before 1400 that functioned as libraries.  Depositories were increased regardless of location, funds, size and function. Raymond Irwin writes, "It is in Chaucer that we first meet with the word 'study,' the history of the study and the history of the domestic library after all, are much the same thing."  Thomas Kelly notes that Chaucer was "the possessor of a considerable library," and this acquisition of books was part of the transformation of English letters, the "revival of English as a literary language."  If one reads The Legend of Good Women's "sixty bokes olde and newe / Hast thow thyself" (LGW Text G 273-274) as autobiographical, then Chaucer's library was a "considerable collection" in the fourteenth century, especially since a single "book" could actually have been a multivolume compilation of many independent works. 
It would be worthwhile to synthesize the records of royal decrees, letters of appointments, diplomatic itineraries, wills, purchases and transfers of property, lawsuits, and other public documents to embed Chaucer's fiction with biographic fact. Such research could identify where Chaucer read or how he procured his materials.  As he had multiple sources of The Consolation of Philosophy, the conditions in which he read become pivotal, particularly if he translated at a site whose purpose was to facilitate reading by offering multiple texts and scholars who could access them. Those who were trained to collect and catalog would have been a harbinger of expression for a fictional transmission of texts. Did Chaucer own the copies of The Consolation in a personal library, or did he access them at a cathedral, monastic, university, private, or royal library? If he had read inside the facilities at Canterbury, which held collections of depth, he would have found it a receptive institution "in the habit of lending books to persons who were not members of it, and even to laymen."  He could have requested interlibrary loans, as it was a "common method" to borrow through a "pledge" of security.  However, he would have had to research and transcribe in poorly lit accommodations, where the ink, if not his skin, could freeze on a cold winter day.  It would have been difficult to sift through texts, collect manuscripts, and organize them for transcription in inhospitable circumstances. "The familiar notice requiring silence is a modern invention:" the medieval library was a noisome, poorly-lit, under heated and under ventilated place, a "crowded reading room" that was not operated for the mutual cooperation between the preserver of text and the reader. The trustees of learning worked in an awkward whirlwind that was "murmurous as a hive of bees" and "ill-adapted for profound study." 
From Richard Sharpe one gathers that a medieval researcher learned without a skilled tutor for discovery: the librarian trained in descriptive cataloguing, assisting patrons with annotated lists, capable of instructing the craft of research, is a modern concept. Sharpe describes an erratic leadership rooted in inconsistent talents. The pattern for managers in "active librarianship" was simply ensuring a superficial catalogue, "the marking of books with shelf-marks, ex libris inscriptions and contents lists."  Their techniques had few customer service merits. Collections were not well-organized, materials were not consistently well-preserved, librarians were not well-trained -not by 21st century certification standards and reading rooms were not designed for comfort in long hours of study. No medieval patron could have failed to notice how organization guided effective use of holdings. With scanty corroborative evidence about Chaucer's personal experience, it is necessary to look at his literary footprints to surmise the mindset of patronage. 
Medieval Literature and Language
Chaucer's debt to literature is more certain than his personal rewards from reading, transcribing, and borrowing in the medieval library. His facility with words emanates from Latin, Italian, French, and Old and Middle English. With such diversity it is difficult to decide why he chose the word that he did to represent the "library" as it is understood today, as a place for the accumulation of books, although for Chaucer not as an intrinsic force to education. Christopher Cannon writes of a "constitutive vagueness" in past studies that have attempted any "historic and linguistic precision"  in the rationale for a lexicon. Nevertheless, Chaucer makes fertile innovations to English using established texts: "At the same time that Chaucer was progressively antiquating the very lexical novelty he had fashioned in earlier texts he may also have been throwing away the very new words on which notions of lexical growth have been based."  The implication of modification is that languages are nimbly blended. In Chaucer's Boece, the word "librarye" is used twice early in the treatise (Bo Bk1 Prosa 4 14 and Bk1 Prosa 5 39-40).  All textual and lexical authorities assign Latin roots to that word and most include French as an intermediary. In the relevant passages, the translator S.J. Tester gives the original Latin words as "bibliotheca" and "bibliothecae,"  and both words are translated into modern English as "library." According to the Oxford English Dictionary (OED), the root of the English word "library" is "liber," a Latin word which is "believed to be a use of liber bark (see LIBER), the bark of trees having, according to Roman tradition, been used in early times as a writing material."  While the Latin "libraria," or a word with a variant spelling, was common in Latin manuscripts in Medieval England, the OED gives an approximation for the first English usage as circa 1374 with a stated uncertainty about the conjecture that "libra," meaning a "book," is the root: "The Rom. word admits of being viewed as f. libra book + -ar a, but this leaves the ultimate analysis unaltered."  Wayne Wiegand and Donald G. Davis trace a history back to those appointed to the care of books: "Early Roman librarians (biblothecarius or magister) tended to be scholars. Other library staff positions included the generalist cataloger and copyist (librarius).... [emphasis given by Wiegand and Davis]."  According to the OED, another word designating a library was used during Chaucer's lifetime, but not by him: "armaries," one of the many forms of "ambry" or "armary," first signified a library in the year 1382.  However, the Middle English Dictionary (MED) finds a first use long before the birth of Chaucer and affirms that "almarie" was used as early as 1225 in the Winteney version of The Benedictine Rule in the line "Sume boc of bare bibliotecan, bast is of bam almeri3e."  The English "almarie," related to the French medieval "aumaire," is listed by the MED as "A bookcase; a store of books, a library; (b) a storehouse of knowledge; a chronicle, a commentary."  Regardless of the disparity between lexical authorities, an "almarie" historically signified a collection of books to be used for devotion and study by monks, who built reading spaces for books that were "frequently stacked on their sides on the shelves of armaria, or book presses, with hinged doors." 
There is a maze of awkward interconnection within the philological morphology. Cannon does not date word roots, but notates the extensive borrowings that Chaucer makes from Latin, French, and Old English. "Librarie" is listed as a derivation from Anglo-French and Continental French sources.  In the OED Etymology section, "librarie" is a French word first used in 1380: it has transformed in the French so that it now designates a "bookseller's shop."  Another Latin word which embodies the modern concept of a library is "study." Cannon notes a broader tracing for "study," a word with its roots in Old French, Anglo-French, and Latin.  The OED cites the word as a mark of sympathy in the...