To set the gutter margin in word you follow these steps.
How to set a left gutter margin.
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.
In the gutter box enter a width for the gutter margin.
The gutter margin is a typographical term used to designate an additional margin added to a page layout to compensate for the part of the paper made unusable by the binding process.
The gutter size is set to 0 25 inches and left margin is set to 0 5 inches.
But in addition to that margin you also want a gutter.
On the page layout tab in the page setup group click margins.
This feature is not available in word online.
The gutter is the amount of the book that you lose to the binding process.
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.
This margin setting will be used in each new document you create based on that template.
Select set as default to set the new margin settings as the default for the current template.
Gutter margins for binding.
Select ok when you re finished.
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.
Change the size for the top bottom left and right 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.
Word typically allows you to choose whether to position the gutter margin of your document at the top or left of the page.
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.
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.
The gutter goes on the left side of right hand pages and on the right side of left hand pages.
In this layout scenario the gutter margin is typically the area where you might three hole punch your paper.
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.