Please note that this is a scanned copy of a paper originally published in 1994, so the text is not as clear as in documents created as pdf files. Passive stack ventilation is a means of removing unwanted moisture from dwellings. The proper design and installation of these systems is vital to their successful performance. This paper gives detailed guidance on this subject and is in support of the 1995 edition of the Approved Document to Part F of the Building Regulations. 6 pages.