Deriving a grid from the type, not from a template

The four rectangles

Every page has them, and confusing them produces most layout problems.

• Trim: the finished page. A5 is 148 × 210 mm.
• Bleed: artwork extending past trim, normally 3 mm.
• Margin: where the text block starts.
• Column and gutter: the subdivisions of the text block and the gaps between them.

Margins are a design decision and there is no universal correct answer, but there is a useful starting point: make the outer margin larger than the inner, and the bottom larger than the top. The page then looks optically centred rather than sitting low, and the reader’s thumb has somewhere to go.

A workable default for a book page: top 15 mm, outer 18 mm, bottom 20 mm, inner 20 mm. The inner is larger because binding eats some of it.

The gutter allowance, which depends on binding

On a bound book, part of the inner margin disappears into the spine. How much depends on how it is bound:

• Saddle stitch (stapled through the fold): very little loss, but pages near the centre creep outwards, which the last lesson of this module covers.
• Perfect binding (glued spine, as on most paperbacks): the page curves into the spine and roughly 3 to 6 mm becomes hard to read. Add that to the inner margin.
• Wire-o or spiral: the punch holes need 8 to 12 mm clear.
• Case binding (hardback): similar to perfect binding plus the hinge.

Ask the binder before setting the margins. It is a one-line question and it is not recoverable afterwards.

Deriving the grid from the body text

Most people pick a grid from a template and then fit the type to it. That is backwards, and it is why so many layouts have awkward line lengths.

Do it the other way:

1. Choose the body size and leading. Say 10 pt on 14 pt.
2. Set the measure from the type. 45 to 75 characters. At 10 pt in a typical text face that is roughly 80 to 110 mm. Take 95 mm.
3. That is your column width. Now decide how many columns fit the page, with gutters wide enough to keep columns separate: a gutter of about 5 mm, or one to two times the type size, is normal.
4. The margins are what is left. Adjust them to the proportions above, then let the column width shift a millimetre or two to make the arithmetic close.

The result is a grid where the text is comfortable to read, because the reading came first.

Columns and the modular grid

A single text column suits a novel. A magazine or a report usually wants more flexibility, and the standard technique is to divide the page into more columns than you use (a 12-column grid) and then span them: text across 8 columns, a sidebar across 4, an image across all 12, a caption across 3.

Twelve is popular because it divides by 2, 3, 4 and 6, so you can make halves, thirds, quarters and sixths without a new grid. The same reasoning is why web layouts use it.

Add horizontal divisions too (a modular grid) if the document has repeated card-like elements. Set the row height to a multiple of the baseline leading so type still lands on the baseline grid.

Setting it up

• InDesign: File ▸ Document Setup for trim and bleed; Layout ▸ Margins and Columns for the rest; Layout ▸ Create Guides for a modular grid.
• Scribus: File ▸ Document Setup ▸ Document for size and margins, Page ▸ Manage Guides ▸ Column/Row for an automatic grid, and the Bleeds tab under Document Setup.
• Affinity Publisher: Document Setup, then View ▸ Guides Manager and the Columns section.

Set all of it on the master page, not on page one. A grid that exists only on the first spread is a suggestion.

The check

Print a spread at 100% and hold it at reading distance. If the text block looks low on the page, your bottom margin is too small. If your eye loses its place returning to the start of a line, the measure is too long. Both are faster to diagnose on paper than on screen, because on screen you cannot see the page edges honestly.