What's the Flap about?

You may think that an article about envelope flaps is going to be boooring. Au contraire! Make an uninformed decision and it can double the cost of your mailshop. And paying out that extra moola is not the least bit boring, I assure you.

Like so many things, the devil is in the details. Let’s start at the beginning.

Every envelope has a flap. Some are well behaved citizens of the direct mail world; others are renegades and outliers, turning economical machine-worked jobs into costly hand-worked jobs.

Here’s what you need to know to keep out of trouble. Most of the time.

Flaps can be triangular, curved or square. Beauty is in the eye of the beholder. But make the flap longer than 2” deep at its deepest point and your budget is in trouble. Your machine-insertable envelope moves over into the more expensive handwork section of the mailshop. Ouch! Your wallet took a big ding.

Flaps need to be on the longest dimension of the envelope. Envelope manufacturers call this format a “booklet” envelope. Flaps opening on the shortest dimension are a “catalog” envelope. Here’s an easy way to remember when you order: Bs (booklets) are better than Cs (catalogs). Just like in high school. Got it?

Flaps can close with glue or with a tear-off strip that exposes the self-adhering glue. Glue is great for machine-insertable jobs. Choose envelopes with the tear-off strip and you can expect to pay for hand sealing. Choose envelopes with a deep V flap and you’ll have a hand sealing project, too.

But not all glue strips are created equal, either. If you’re intending to use real lick ‘em stick ‘em (ie “live”) stamps, then select a glue strip that is gfl (“Gummed for Live”). Gfl glue strips stop before they get to the area where the stamp will be glued. Since mailshops typically stamp envelopes before inserting, a gfl glue strip ensures that moisture from the stamp doesn’t cause the envelope to self-seal before insertion.

And you thought you were just buying envelopes! I could go on about color, texture, windows of regular, diagonal or side seams, but I’ll spare you those gruesome details today.

For today, if I can but make a flap over the flap and get you to see why even the tiniest details are critical to your bottom line, then my job here is done.

I shall return.