HowTo_AvoidInterleafPage

How can empty left pages be prevented in scrbook?

There are various kinds of blank left pages in books. This article primarily covers blank left pages at the beginning of chapters and when transitioning to a new page numbering style. As a third option, blank left pages may also appear before the start of a new part or as the reverse side of a page with the part heading.

Beginning of chapters

In double-page booksetting, new chapters normally always start on a right-hand page. Therefore, if the previous chapter already ends on a right page, a blank left page must be inserted. In the KOMA script classes scrbook and scrreprt this affects the commands \chapter, \chapter*, \addchap, \addchap* and generally all headings in the style chapter (see \DeclareSectionCommand). This so-called vacant page (sometime also called interleaf page) is controlled in double-page typesetting by option open:

• open=right: (default with scrbook)
  chapters always start on the right, \cleardoublepage is equivalent to \cleardoubleoddpage.
• open=left:
  chapters always start on the left, \cleardoublepage is equivalent to \cleardoubleevenpage.
• open=any:
  chapters are free to start in left or right, \cleardoublepage is equivalent to \cleardoubleoddpage.

So to avoid empty left pages before chapter headings, you should set option the open=any usually as an optional argument to \documentclass:

\documentclass[open=any]{scrbook}
\begin{document}
\chapter{First Chapter}
This is a right-hand side of a double page.
\chapter{Second Chapter}
This is a left-hand side of a double page.
\end{document}

Note: As long as you don't use the twoside=false or twoside option in the scrreprt class, the open option is unnecessary.

\documentclass{scrreprt}
\begin{document}
\chapter{First Chapter}
This is a right-hand side.
\chapter{Second Chapter}
This is an even numbered page but nevertheless a right-hand side.
\end{document}

\documentclass[twoside]{scrreprt}
\begin{document}
\chapter{First Chapter}
This is a right-hand side of a double page.
\chapter{First Chapter}
This is a left-hand side of a double page.
\end{document}

\documentclass[twoside,open=right]{scrreprt}
\begin{document}
\chapter{First Chapter}
This is a right-hand side of a double page.
\chapter{Second Chapter}
This is also a right-hand side of a double page.
\end{document}

Because of the resulting inconsistency, I do not recommend changing the option within the document. However, it may be feasible to apply the command \KOMAoption or \KOMAoptions in certain instances:

\documentclass{scrbook}
\usepackage[ngerman,main=english]{babel}
\begin{document}
\tableofcontents
\KOMAoption{open}{left}
\addchap{Abstract}
This is the abstract in English at a left page.
\KOMAoptions{open=right}
\selectlanguage{ngerman}
\addchap{Zusammenfassung}
Das ist die Zusammenfassung auf Deutsch und einer rechten Seite.
\end{document}

The example illustrates how to position the English "Abstract" on the left-hand side and the German "Zusammenfassung" on the right-hand side of a double page.

Transition to new page numbering style

When changing the style of page numbers in the course of using \frontmatter and \mainmatter, a blank Left page may also be inserted. This happens exactly when the front part ends on a right page, for example page iii. Since the main part always starts on page 1, an empty left page must then inevitably be inserted. This is because odd numbered pages are always a right page. If no blank left page were inserted, a double-sided printout would print a right page on a back page, i.e. a left page. From this point on, all margins would be wrong.

Since this possibly resulting blank page is mandatory, it should not be switched off. Of course there are tricks for this, but I strongly advise against it. If you don't want this blank page, you really don't want a double-sided document and should set twoside=false at \documentclass.

If you change the page numbering style manually by using \pagenumbering, you are responsible for inserting a blank page if necessary. The easiest way to do this is to use the \cleardoubleoddpage statement immediately before \pagenumbering{...}.

Starting a new part

Just as with chapters, the part heading, i.e. \part, \part*, \addpart, \addpart* or generally all headings in the style part for the beginning of the new part takes account to option open. For the empty page after the part heading this is only conditionally true. In fact, similar to the change between the front matter and the main matter, this page is always defined as an empty verso page. Therefore it exists only in the double-page typesetting and only with open=right. Both is the default in scrbook. If necessary, however, you can change this by redefining \partheademptypage. See the use manual. This way you can also add additional information to this verso page, for example a picture:

\documentclass{scrbook}
\usepackage{mwe}
\renewcommand*{\partheademptypage}{%
  \thispagestyle{empty}
  \vspace*{\fill}
  \includegraphics{example-image-\alph{part}}
  \vfill
  \newpage
}
\begin{document}
\part{First Part}
\chapter{First Chapter}
\blindtext
\part{Second Part}
\chapter{Second Chapter}
\blindtext
\end{document}