While its original pronunciation is not known with certainty, modern Egyptology assigns it the value of per, but purely on the basis of a convention specific to the discipline.
However, the Ancient Greek rendering of the title pr-`3 as Ancient Greek: φαραώ pharaō suggests the reconstruction of the historical (Late Egyptian) pronunciation as *par, see Pharaoh#Etymology.
The "house of life" is a library for papyrus books-(scrolls), as well as a possible scriptorium.
Pr is one of hieroglyphs adopted into the Proto-Sinaitic script, the earliest known alphabetic writing system.
It was used to represent the phoneme /b/ as in bayt, the Canaanite word for "house", after the hieroglyph's original meaning.