In double parallel folds the paper is folded in half and then folded in half again with a fold parallel to the first fold. One half of the sheet of paper is nested inside the other half. There are three folds and 8 panels (4 on each side of the sheet of paper).
Using standard letter size paper you would end up with a piece with narrower panels (approx. 2.75") than the usual C fold (tri-fold). Double parallel fold brochures are often done on longer 8.5 x 14 (legal size) or longer sheets giving you approximately 3.5" wide panels — only slightly smaller than a tri-fold letter size brochure but you gain 2 panels.
Sizing and Folding Your Panels
Opened flat, looking at what would be the inside of the piece, the two panels on the left (a & b in sidebar middle image) are the larger panels and the two on the right (c & d) are smaller. To allow for proper nesting the two inside folded panels (2 panels on the right) are 1/32" to 1/8" smaller than the two outer panels (2 panels on the left).
Adapt this procedure for the specific paper size you are using. In these calculations I'm using an 8.5 x 14 (legal size) sheet of paper. For thicker paper you may want to use 1/8" and 1/4" in place of 1/32" and 1/16" in steps 2 & 3. Try it both ways with your paper of choice to find which folds better before you start laying out your brochure.
- Take the length of the sheet of paper and divide by 4: 14 / 4 = 3.5 inches This is your starting panel size.
- Add 1/32" (.03125) to that measurement: 3.5 + .03125 = 3.53125 inches This is the size of your two larger panels (a & b).
- Subtract 1/16" (.0625) from your large panel size: 3.53125 - .0625 = 3.46875 inches This is the size of your two smaller panels (c & d).
Consider a double parallel fold for advertising pieces and brochures.
"The way the consumer reads the brochure... makes a great differen[ce] in how you layout a brochure. The double parallel brochure is one of those brochures where you need to look at the panels and lay the information following that basic pattern, but that pattern also has to work in a general layout. This means you have to be able to look at this brochure from two different points of view (POV)." — Read more at The Double Parallel Brochure by Cassandra Goduti
The front panel (reverse of panel a) is generally the first part viewed. Then, it might be opened half way so that the reverse side of panels c & d are viewed next or the consumer may open it up completely and view the full 4 panel (a,b,c,d) inside spread. The "back" of the folded brochure is the reverse side of panel b. Print up a draft of each layout, folding and unfolding in different ways to make sure the copy flows in a natural, logical manner for most directions.
Variations and Other 8 Panel Folds
A variation on this fold, the stepped double parallel, creates a tabbed effect by changing the panel sizes so the first panel is shorter, the two middle panels are larger and the end panel is shortened a bit so you see the front panel and a bit of two other panels when the piece is folded.
Note that a 6-panel fold may be described as a 3-panel while an 8-panel may be described as being a 4-panel layout. 6 and 8 refer to both sides of the sheet of paper while 3 and 4 are counting 1 panel as being both sides of the sheet. Sometimes "page" is used to mean a panel.
- Double Gatefold is similar to the double parallel but the two end panels fold in toward the middle
- Accordian or Zig Zag folds with 3 parallel folds make 8 panels
- Spiral Folds with 3 parallel folds would produce 8 panels
- French Fold produces 8 panels of even or uneven sizes using crossfolds
See Folding a Brochure for measurements in inches and picas for three different sizes of double parallel folds.
Also Known As: parallel fold | double fold | quarter fold (not to be confused with a quarter fold/french fold)