If you have previously set your document to the mirror margins book fold or two pages per sheet layout options word will automatically set the gutter margins to a position that matches the chosen layout.
How to set a left gutter margin.
The gutter goes on the left side of right hand pages and on the right side of left hand pages.
Word allows you to specify a gutter margin at either the left or top edges of the page provided you are using a single sheet layout.
Select ok when you re finished.
So yes you have a half inch margin on the left and the right to have white space to keep your book easy to read.
Gutter margins for binding.
On the page layout tab in the page setup group click margins.
In a facing pages layout word refers to this type of layout as mirror margins the gutter margin is on the very inside of both pages.
To set the gutter margin in word you follow these steps.
In this layout scenario the gutter margin is typically the area where you might three hole punch your paper.
This feature is not available in word online.
This margin setting will be used in each new document you create based on that template.
Display the page layout tab of the ribbon.
Set left margin right margin and gutter size this example uses the gutter setting to leave room on the left side of the page for binding the report.
Word typically allows you to choose whether to position the gutter margin of your document at the top or left of the page.
To set the gutter margin.
A gutter margin adds extra space to the side margin top margin or inside margins of a document that you plan to bind to help ensure that text isn t obscured by binding.
In the gutter box enter a width for the gutter margin.
While word for the web will honor a gutter margin set in word for the desktop it only supports changing the top bottom left and right margins.
But in addition to that margin you also want a gutter.
Change the size for the top bottom left and right margins.
Mirror margins for facing pages.
Select set as default to set the new margin settings as the default for the current template.